The fruit quality of different varieties (lines) of cultivated ginseng fruit in Shilin county was tested and evaluated to provide guidance for the development of ginseng fruit industry. Seven fruit quality indexes of soluble sugar, soluble protein, soluble solid, mineral elements, vitamin C, cellulose and amino acid were determined by using eight main ginseng fruit varieties (lines) of Dayuangguo, Yuangguo No. 1, Yuangguo No. 2, Yuangguo No. 3, Shiyou No. 1, Shiyou No. 2, Shiyou No. 3 and Ruiyu cultivated in the field of Shilin county. By multiple comparison of quality indexes of Panax ginseng fruit, it was found that the content of soluble sugar in Yuanguo No. 2 was the highest, while that in Dayuanguo and Yuanguo No. 3 was the lowest; The soluble protein content of Shiyou No. 2 was the highest, and that of Shiyou No. 1 and Ruiyu was the lowest; The content of soluble solids of Yuanguo No. 2 was the highest, while that of big round fruit was the lowest; Shiyou No. 3 has the highest content of vitamin C and Yuanguo No. 3 has the lowest content; The crude fiber content of Yuanguo No. 2 was the highest, and that of Shiyou No. 1 was the lowest; The content of trace elements in Yuanguo No. 2 was the highest, while that in Yuanguo No. 3 was the lowest; The amino acid content of big round fruit was the highest, and that of Shiyou No. 2 was the lowest. There were significant correlations between the quality indicators of different varieties (lines), among which soluble sugar and soluble solids were significantly correlated with each other (P<0.05). The principal component analysis of 6 quality indicators was carried out, and the cumulative contribution of the first three principal components reached 83.955%, which could reflect most of the information of the original quality index. The resulting comprehensive evaluation system was established to evaluate eight different varieties (lines) of ginseng fruit. In conclusion, the above eight ginseng fruit varieties (lines) all contain rich nutritional components, among which Yuanguo No. 2 has the best comprehensive quality, and can be selected as the parent material for the main variety or new germplasm creation.

Curcuma alsimatifolia is a perennial bulbous herb of the genus Curcuma in the Gingeraceae.family The inflorescence of C. alismatifolia resembles tulips and enjoys the reputation of “tropical tulips”. C. alsimatifolia was introduced into China from Thailand and it is acclaimed by an ever-increasing number of consumers. The varieties of C. alismatifolia are relying on import in China today. The lack of new varieties with proprietary intellectual property rights limits the development of C. alismatifolia industry in China. Three different cross combinations of 327 hybrid offspring were constructed using the Siam TM Sitrone variety of C. alismatifolia as the female parent to breed new varieties of C. alismatifolia with independent intellectual property rights and increase the variety diversity. Eleven pairs of SSR primers were selected to analyze the hybrid F₁ generation of the three cross combinations and the parents, and five pairs of specific SSR primers were selected for each cross combination to identify the authenticity of the hybrid F₁ generation. The genetic segregation pattern and genetic diversity and genetic relationship of the parental and hybrid F₁ generation populations were also analyzed. The results showed that the eleven pairs of SSR markers had high resolution and good amplification polymorphism for the three parental materials, and each parent had its specific SSR markers, which could effectively identify the genetic authenticity of the hybrid offspring. True hybridization rates of 91.8%, 90.8% and 93.4% were identified in 327 F₁ individuals The SSR molecular marker primers had high polymorphism and could be directly used for C. alismatifolia genetic diversity analysis, hybrid identification and other related studies, providing efficient and reliable SSR marker selection for future identification of hybrid progeny, while the identified true C. alismatifolia progeny population could provide germplasm for genetic studies of superior traits. The identification of authentic C. alismatifolia progeny could provide germplasm materials for genetic research on superior traits and provide scientific basis for the selection of new varieties.

Fujian Shuixian belongs to the semi-tree form of tea plant (Camellia sinensis), which is the main variety for processing Wuyi Rock Tea (WRT). At present, there is a widely phenomenon that Shuixian grows naturally (no-pruning) in the management of tea gardens of Wuyishan, and its quality is obviously different from that of pruned Shuixian. In order to clarify the basis and differences of aroma and flavor substances WRT under natural growth and pruning conditions, this study used gas chromatography-mass spectrometry (GC-MS) and high performance liquid chromatography (HPLC) technology, combined with multivariate statistical analysis, to explore the internal relationship among aroma substances, flavor components and quality of WRT before baking (raw tea) and after baking (finished tea) under natural growth and pruning conditions. The results showed that 261 volatile compounds were identified by GC-MS technology. It reveals that there are obvious differences in aroma substances between raw tea and finished tea of the natural growth Shuixian and pruned Shuixian with the help of principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA). Compared with the raw tea of pruning Shuixian, the raw tea of natural growth Shuixian showed significant differences in 41 volatile substances (Selection standard: VIP>1, and the FC≥1.5 or the FC≤0.67), in which the relative content of hexyl hexanoate, plant alcohol, isophytol, trans-nerolidol are higher, however, the relative content of β-cedrene, γ-junitene and 2-methoxyfuran are lower. Compared with the finished tea of pruning Shuixian, the finished tea of natural growth Shuixian showed significant differences in 71 volatile substances, such as hexyl hexanoate, methyl caproate, trans-nerolidol, (Z)-β-farnesene, 1-heptanol, 2-heptanone with fruity aroma, and 3-ethyl-1H-pyrrole, 2-formyl-4with baking aroma, whose relative content are higher. There are also great differences in aroma substances between natural growth Shuixian and pruned Shuixian before and after baking, with 91 and 70 different substances respectively. The analysis of aroma activity value (OAV) showed that (E)-3-hexenol, indole, trans-nerolidol, epoxy-β-ionone, (E)-linalool oxide, 2-phenylethanol and methyl salicylate may be important substances for the aroma formation of natural growth Shuixian. Analysis of the main flavor substances showed that there were obvious differences in catechin components and caffeine between natural growth Shuixian and pruned Shuixian. The results of sensory evaluation are consistent with the results of physical and chemical test, showing that natural growth Shuixian with rich fruit fragrance, mellow taste and better quality. This study has a guiding role in scientific management of tea gardens and tea quality control.

To further explore the molecular characteristics and pathogenicity of Sri Lankan cassava mosaic virus (SLCMV) isolates in China. Mosaic cassava leaves were detected, and the domestic SLCMV isolates full-length genomes of DNA-A and DNA-B were obtained by PCR amplification. It`s nucleic acid and amino acid sequence characteristics were analyzed by bioinformatics software. The infectious clones of strong and weak pathogenic isolates (SLCMV-Colombo and SLCMV-DG1922) were constructed. The DNA-A and DNA-B components of the two virulence isolates were recombined, and the pathogenicity differences of the two isolates were compared by tobacco (Nicotiana tabacum) inoculation. The results showed that SLCMV isolates belong to “Old World begomoviruses” encoding 8 open reading frames (ORFs) including the AV2 gene. It has a typical common region (CR), repeat sequence, TATA Box and TAATATT↓AC stem-loop structure of Geminiviruses, and 7-amino-acid are missing at the carboxyl terminal of Rep protein. Domestic SLCMV genome, coding and non-coding region sequences were 97.0%-100.0% similar to the isolates from Cambodia, Thailand and Vietnam, and 86.5%-98.6% similar to the early isolates from India and Sri Lanka. Coding region of DNA-B were 95.0%-97.6% similar to Indian cassava mosaic virus strain (ICMV), were less than 80.0% to the other 9 African cassava mosaic virus strains. Infection clone inoculation showed that the DNA-A (ColA) component of the strong virulent isolate SLCMV-Col played an important role in the typical mosaic symptoms of N. tabacum leaves, while the DNA-B (DG1922-B) of the domestic isolate could cooperate with Col-A to produce strong pathogenicity to tobacco plants. This study analyzed the whole genome structure of SLCMV in China, the infectious clone and its technology provide an important research basis for further pathogenesis research of SLCMV.

The alkaloid content of different samples in different seasons and different developmental stages of MHLC of two tea varieties, Nongdao Yecha (MHLC) and Yunkang 10 (YK10) was determined by HPLC. Caffeine synthase 1 gene (TCS1) was cloned from the cDNA of tea plant by RT-PCR in different samples, and its expression level was analyzed. The results showed that MHLC was a natural tea germplasm resource with low caffeine and high theobromine. Theobromine content of MHLC in different seasons was greater than 23.00 mg/g, while the caffeine content was less than 4.00 mg/g. In addition, the accumulation of caffeine and theobromine in MHLC shoots was the highest, and the leaves at the same stage had higher caffeine and theobromine than stems, and the caffeine and theobromine in leaves and stems gradually decreased with the increase of maturity. Through gene cloning and quantitative analysis, it was found that MHLC had two TCS1 allelic variants: TCS1b (with only theobromine synthase activity) and TCS1d (with both theobromine and caffeine synthase activities). Among them, the high expression of TCS1b and the extremely low expression of TCS1d are likely to be the key reasons for MHLC high theobromine and low caffeine. This research would provide material for low-caffeine tea breeding and molecular basis for the efficient utilization of MHLC.

The aim of the study is to estimate the effects of different mulching treatments on the photosynthetic characteristics of leaves, soil physical properties and yield of Amorphophallus muelleri intercropped in rubber plantations. Seven treatments (silver film, black film, white film, straw mat, thickened black film, microporous black film and no mulch (CK) were set up in this experiment. Photosynthetic characteristics of A. muelleri leaves at the three stages of head changing, corm and maturity were measured and analyzed. Net photosynthetic rate (P_n), stomatal conductance(G_s), transpiration rate(T_r), intercellular CO₂ concentration(C_i), electron transfer rate(ETR), physiological characteristics parameters including soluble protein(SP) content, soluble sugar(SS) content, chlorophyll(Chl) content, chlorophyll a/b(Chl a/b). soil in situ physical properties including soil moisture comtent (SMC), soil conductivity(SC), soil temperature (ST), and underground corm yield of A. muelleri were assayed. The photosynthetic parameters (P_n, G_s, T_r and ETR) of A. muelleri leaves increased by different plastic film mulching treatments at the same period. P_n, G_s and T_r of straw mat treatment at the head changing stage and expansion stage were significantly higher than those of the other treatments (P<0.05), the amplitude of the other treatments fluctuated irregularly and there were significant differences among them. At the mature stage, SP and Chl of A. muelleri leaves under different treatments were significantly higher than those under the control in the same period, and there was no significant difference among all treatments. In the same period, the SS and Chl a/b of A. muelleri leaves under different treatments were slightly different. The SS of each treatment at the maturity stage was significantly higher than that of the control, and the SS of the control at the three stages was the lowest, while the Chl a/b of e plastic film treatment at the maturity stage was not significantly different from that of the control. In the same period, SMC and SC by different plastic films were higher than those of the control. The water retention effect of thickened black film treatment was the best, the SC of microporous black film treatment in the expansion stage and straw mat treatment in the maturity stage were significantly the highest, but there was no significant difference in SMC and SC among other treatments. P_n, G_s, T_r, ETR, SP, and Chl of the same mulch treatment at different stages were all in the following order: head changing stage>expansion stage>maturity stage, while the SS and Chl a/b of each treatment were in the following order: maturity stage>expansion stage>head changing stage. According to the results of correlation analysis between all indexes and yield, except ST and yield were negatively correlated, other indexes were positively correlated with yield. Compared with the control, different plastic film mulches increased the yield of A. muelleri. Black mulching, straw mat and thickened black mulching treatments significantly increased the yield, while white mulching and microporous black mulching treatments did not significantly increased the yield. Therefore, silver plastic film, black plastic film, straw mat and thickened black plastic film are suitable choices for A. muelleri to increase the production and efficiency in practical production.

Pterocarpus santalinus is one of the most famous rosewood (Hongmu) species in the world. Its large-scale development is restricted due to limited seed production in China. A grafted clone seed orchard was established recently using suprior tree materials by Experiment Station of Research Institute of Tropical Forestry, Chinese Academy of Forestry in Jianfengling, Hainan Island, and most trees in the orchard have flowered and fruited. The differences in seed quality among superior trees in the introduction garden and the grafted clones need to be studied. Here the morphological traits were measured, and germination tests were conducted for the seeds of P. santalinus collected from six superior trees in the introduction garden and the grafted clones in the seed orchard at the experiment station. The coefficients of variance for the seed morphological traits were much lower than those for seedling growth traits among superior trees or the grafted clones, and the coefficients of variance was the lowest for the weight of 1000-grain seeds, indicating that the variations of seedling growth were more abundant than those of seed morphorlogy Seed length was significantly different at 0.05 level among the superior trees with No. 7 performing the best, and seed length, width and thickness differed remarkably among the grafted clones, in which No. 9^# performed the best in seed length and width, and No. 7^# did the best in seed thickness. The germination rate and potential differed significantly among superior trees (No. 3 and No. 9 performed the best, respectively) or the clones (No. 5^# did the best), and significant difference occurred in the length of epicotyl, hypocotyl, radicle and total seedling among the superior trees (No. 3 did the best), and in the length of radicle and total seedling among the grafted clones (No. 7^# did the best), demonstrating that abundant variation in seed germination and seedling growth existed among superior trees and among the grafted clones. Significance of difference between each superior tree and its clone varied with gene type, and clones performed as a whole, better than relevant superior trees in seed length and width, seed germination and seedling growth. It was indicated from relationship analysis that seed weight was significantly correlated with germination rate at 0.01 level, the germination rate of the plumper seeds was higher. In conclusion, seeds from the grafted clone seed orchard performed better in the seed morphorlogy and germination than those from the superior trees in the introduction garden, and significant difference was absent in seed weight among the superior trees or the grafted clones, and between each superior tree and its clone (P≥0.05), the seeds developed fully in the seed orchard with 1000-grain weight near 100 g, more than that for scattered individuals early grafted (92.9 g). The findings would provide scientific evidences for elite variety selection, seed orchard establishment and robust seedling cultivation.

A time-saving, efficient and environmentally friendly method for the preparation of soluble dietary fiber (SDF) from coffee peel with ultrasound-assisted low eutectic solvents (UAE-DESs) was established for the first time, and its process parameters were optimized by single-factor test and response surface test to further explore a new green method for the preparation of soluble dietary fiber from coffee peel. Eight choline chloride-based deep eutectic solvents were prepared as extraction solvents by the heating method and compared with the conventional water extraction method. The results showed that the deep eutectic solvent system with a 1∶2 molar ratio of choline chloride to urea prepared the highest yield of soluble dietary fiber from coffee peel at 10.10%±0.11%, which was significantly higher than that of the conventional water extraction method at 6.50%±0.22%. The effects of DES composition (molar ratio, water content, liquid-to-solid ratio) and ultrasonic treatment (ultrasonic power, ultrasonic time) on the yield of soluble dietary fiber from coffee peel were investigated by single-factor experiments. The response surface methodology (RSM) combined with Box-Behnken design (BBD) was used to optimize the soluble dietary fiber yield and investigate the effects of deep eutectic solvent water content, liquid-solid ratio, ultrasonic power and ultrasonic time on the yield of soluble dietary fiber. Based on the optimization results of RSM, the optimal preparation conditions were determined as follows: water content of deep eutectic solvent 39.91%, liquid-solid ratio 32.37 mL/g, ultrasonic power 305.20 W, and ultrasonic time 33.80 min. Under this condition, the maximum soluble dietary fiber yield of coffee peel was 10.74%±0.14%, which was close to the predicted soluble dietary fiber value of 10.80%. Therefore, as an efficient and non-polluting green solvent, deep eutectic solvent can be used for the preparation of soluble dietary fiber from coffee peel. The results of this study would provide new ideas and theoretical references for the preparation of soluble dietary fiber from coffee peel, and have potential applications in the value-added utilization of coffee by-products, the production of new high value-added products and the development of natural functional foods.

Anthracnose is a common disease of coffee, which causes serious loss to the yield and quality of coffee fruit. The research on pathogenicity and biological characteristics of the pathogenic bacteria causing coffee anthracnose and screening of effective antagonists would provide reference for the biological control of coffee anthracnose. Four coffee anthracnose pathogens Wyq1 (Colletotrichum siamense), Yyq1 (C. fructicola), Xbd1 (C. gloeosporioides) and Hb1 (C. theobromicola) were isolated and tested for pathogenicity by spore suspension, and the most virulent strains were selected for further experiments. The biological characteristics of the pathogenic bacteria were studied by the plate culture method. Screening of antagonistic bacteria was done by the plate confrontation method. Xbd1 strain could infect healthy coffee leaves, and its virulence was the strongest among the four strains. The most suitable medium for the vegetative growth was PDA. The optimal nitrogen source was tryptone. The most suitable carbon source was glucose. The optimum temperature was 28 ℃. The optimal pH was 7. The difference of vegetative growth was not significant under different light conditions. Bacillus subtilis MC4-2, B. tequilensis D5-8, B. velezensis MC2-1 and B. flexus ZLSY3 and B. amyloliticus GJ7 showed good antagonistic effect in indoor screening. B. subtilis MC4-2 had the best antagonistic effect, with an inhibitory rate of 57.8%. The study would lay the foundation for the control of anthrax and the development of biocontrol agents.

Dendrobium kingianum belongs to Orchidaceae family, which is widely grown as an ornamental plant in China. In recent years, a blight disease in D. kingianum is observed in Guangdong province, China. This disease infects the stems and leaves of D. kingianum, causing brown rot and plant death. It has a serious impact on production. A fungus was isolated from the diseased plants of D. kingianum. The pathogenicity test showed that this fungus could infect healthy potted plants and cause the disease. The symptoms on inoculated plants were similar to field symptoms. Morphological characteristics of the fungus from the inoculated plants were consistent with that of the original fungus from field samples. The pathogen was identified by both morphological characteristics and β-tubulin (tub) gene sequence analysis. The morphological characteristics of the isolates were similar to Phytophthora palmivora. BLAST results showed both the sequences of two isolates in this study were 99% identical to the sequence of P. palmivora. In the maximum likelihood (ML) tree based on tub gene sequences, the strains in this study clustered with P. palmivora with 100% support. Therefore, P. palmivora was identified as the pathogen of Phytophthora blight on D. kingianum based on morphological characteristics and phylogenetic analysis. This is the first report of P. palmivora causing Phytophthora blight on D. kingianum in China and worldwide. The inhibitory effect of 10 fungicides on P. palmivora was determined using the mycelial growth rate method. The results showed that four fungicides, namely diacetylomyamide, dimethomorph, metalazepine and metalazepine · mancozeb, were the top four toxic to P. palmivora, and the EC₅₀ value was 0.000 03 μg/mL, 0.0628 μg/mL, 0.2381 μg/mL and 0.5457 μg/mL, respectively. It was followed by chlorothalonil, pyrimethole and mancozeb, the EC₅₀ was less than 10 μg/mL. However, the effect of downy mildew hydrochloride and triethylphosphonate was poor, and the EC₅₀ was more than 100 μg/mL. Carbendazim showed no inhibitory effect, the EC₅₀ was more than 1000 μg/mL. The result would provide a theoretical basis for the prevention and control of Phytophthora blight in Dendrobium.

Camellia nitidissima belongs to the genus Camellia of theaceae and belongs to the first-level national protection plant, with high ornamental value and medicinal value. However, at present, there are few wild resources of C. nitidissima. It is necessary to find efficient artificial cultivation methods, rapidly propagate excellent C. nitidissima seedlings, and then greatly improve the yield of large-scale cultivation of C. nitidissima. Arbuscular mycorrhizal (AM) fungi can significantly promote plant growth and development, increase crop yield, and enhance plant stress and disease resistance. Inoculation of AM fungi into C. nitidissima has a positive effect on the cultivation of C. nitidissima. Since almost all AM fungal inoculation test involves the growth of mycorrhizal observation and infection rate determination, and AM infection situation observation methods available are not efficient. An efficient dyeing of AM fungi C. nitidissima was reported. In this study, the effects of five dyes (Sudan red Ⅳ, acid fuchsin, trypan blue, aniline blue and acetic acid ink) on AM fungi of healthy plant roots of C. nitidissima were investigated. The results showed that 5% acetic acid ink staining solution had the best staining effect. Mycelia, vesicles, spores and other structures of AM fungi in root cortex cells were clearly visible, and AM fungi could be clearly distinguished from other unknown fungi, and the root staining effect could be preserved for a long time. The mycelia and vesicles of AM fungi stained with Sudan red Ⅳ and acid fuchsin were not in obvious contrast with the background, and the preservation time of acid fuchsin staining was short, which was not conducive to observation. The dyeing effect of aniline blue and trypan blue was slightly inferior to acetic acid ink, and the price was expensive and the experimental cost was high. The last four dyes are suspected of causing cancer, and the long-term use has great potential safety risks to the health of operators. Acetic acid ink dyeing is simple, low toxicity, low cost and excellent dyeing effect. It is suitable for the staining and section observation of AM fungi in the roots of C. nitidissima. The results would provide new ideas for the future application of C. nitidissima mycorrhizal seedlings.

Guifei mango has bright color and sweet taste, which is deeply loved by consumers. However, the yield and economic benefits of this mango had been seriously affected due to a high fruit abortion rate. Forchlorfenuron (CPPU) is a swelling agent used in the mango industry of Hainan which can improve fruit setting rate, promote fruit enlargement and induce parthenocarpy. But, the abuse of CPPU resulted in a higher percentage of abnormal fruit, the decline of quality, stay-green after harvest and flavor change. To find a appropriate dosage, we compared the effects of CPPU spraying with different concentrations on the yield, quality, postharvest storage characteristics and incidence of disease in mango fruit. The experiment was carried out in a demonstration park of mango standardization production, Chinese Academy of Tropical Agricultural Sciences, Dongfang City, Hainan Province. The Guifei mango trees with healthy, consistent size and vigor were selected as the test material. The age of trees is about 12 years. And CPPU aqueous solutions of 10 mg/L, 20 mg/L and 60 mg/L were sprayed on 15, 25 and 35 days after full bloom, respectively. Distilled water was used as a blank treatment. Six trees were selected for each treatment (3 repetitions). The fruits were harvested at 78 days after flowering, then put into corrugated boxes to avoid damage. All the fruits were brought back to the laboratory and stored in a cold storage at (25±1)℃ and 80%-90% relative humidity (RH). Fruit color parameters (L^* value, a^* value, b^* value) and pericarp pigments (contents of total chlorophylls, anthocyanins and carotenoids) were measured during harvest and storage to evaluate the effect of CPPU on the fruit color. Fruit firmness and contents of soluble solid content (TSS), titratable acid (TA), vitamin C were measured to evaluate the effect of CPPU on inner quality, postharvest storage characteristics and fruit ripening of mango fruit. In addition, the effects of CPPU on yield, single fruit weight of parthenocarpic fruit/pollinated and fruit-shape index were also studied. Spraying 10 mg/L CPPU solution could significantly improve the average yield (45.73 kg), 34.03% higher than the control (34.12 kg). Spraying a CPPU solution of higher concentration (20 mg/L, 60 mg/L) had no obvious effect on yield increase, or even reduced the yield. Spraying 10 mg/L CPPU solution had little effect on the number of fruits per tree. But if spraying CPPU solution of 20 mg/L and 60 mg/L could significantly reduce the number of fruits per tree by 46.08% and 60.19% compared with the control. Spraying 60 mg/L CPPU solution had the most obvious effect, the single fruit weight of pollinated and parthenocarpic fruit increased by 28.48% and 117.25% respectively. Spraying CPPU solution could increase the fruit-shape index of mango, but there was no significant difference compared with the control. Spraying CPPU had a significant effect on the contents of chlorophyll, carotenoid and anthocyanin during maturation and ripening of mango. That fruits treated with CPPU had higher chlorophyll and carotenoid content, lower anthocyanin content, and showed a greener color. The chlorophyll content in a mango peel treated with 10 mg/L, 20 mg/L, 60 mg/L CPPU increased by 5.12%, 8.67%, 9.83% and 21.23%, 36.63%, 48.07% respectively during maturation and ripening compared with the control. And the increase of carotenoid content was more obvious treated with 60 mg/L CPPU than that treated with 10 mg/L and 20 mg/L, the carotenoid content increased 22.56% and 18.81% respectively during maturation and ripening compared with the control. Different from chlorophyll and carotenoids, the content of anthocyanins decreased gradually with the increase of CPPU concentration. The content of anthocyanins decreased by 8.94%, 13.62%, 18.30% and 13.83%, 16.19% and 17.58% respectively treated with 10 mg/L, 20 mg/L, 60 mg/L CPPU during maturation and ripening compared with the control. The process of mango fruits from green to yellow was delayed by CPPU spraying during storage. Spraying CPPU solution could increase fruit firmness and titratable acidity (TA) content, reduce soluble solids content (TSS) content and delay fruit ripening. The incidence rate of anthracnose and stem-end rot decreased after CPPU treated. But in all processing, only the fruits treated with CPPU in doses of 10 mg/L were normal during fruits coloring. In addition, spraying CPPU could prolong the storage time of mango fruits, 60 mg/L CPPU treatment could delay the ripening for 4 days. Spraying 10 mg/L CPPU on 15, 25 and 35 days after full bloom stage could increase fruit-shape index, promote fruit enlargement and increase the mango yield. At the same time, the postharvest fruit treated with 10 mg/L CPPU could delay fruit softening and ripening during storage, reduce the occurrence of postharvest diseases, prolong storage time. Nevertheless, the nutritional quality of fruit was also decreased during ripening with the fruit hardness increased and the TSS content decreased. Spraying higher concentration of CPPU solution (20 mg/L, 60mg/L) had no obvious effect on yield increase, or even reduced the yield. Therefore, we suggest that spraying 10 mg/L CPPU solution in mango production, which could improve the yield, prolong the storage time and ensure the postharvest fruit quality.

In the current study, one newly recorded genera of wild orchids, Neuwiedia Blume, as well as five newly recorded species, including Goodyera brachystegia Hand. -Mazz, Neuwiedia zollingeri var. singapureana (Baker) E. F. de Vogel, Odontochilus drymoglossifolius (Hayata) T. Yukawa, O. saprophyticus (Aver.) Ormerod and O. yakushimensis (Yamam.) T. Yukawa in Fujian province were illustrated. The voucher specimens of the plants are preserved in the Herbarium of Fujian Normal University (FNU). The discovery of the newly recorded orchids has great significance for further studies on the diversity and conservation of Orchidaceae in Fujian, China.

The study was aimed to cope with the rapid increase in demand for patchouli [Pogostemon cablin (Blanco) Benth.] and to solve the problems of lack of patchouli medicinal materials, germplasm degradation, confusion of germplasm sources, and vulnerability to diseases and pests. Callus, cluster buds and rooting seedling of patchouli were irradiated with a gradient dose of ⁶⁰Co-γ rays. The appearance and morphology of regenerated plants were observed, the mutated plants were screened, the agronomic traits and physiological and biochemical indicators were measured, and the content of pogostone and patchouli alcohol, the main volatile components, were determined by gas chromatography-mass spectrometry (GC-MS). The results showed that calluses and cluster buds were more sensitive to ⁶⁰Co-γ rays and had higher mortality rate, while rooting seedlings were more tolerant to ⁶⁰Co-γ rays and had lower mortality. The best way to breed mutagenesis is ⁶⁰Co-γ treated rooting seedlings with irradiation doses of 100 Gy with a mutagenesis rate of up to 10%. In this experiment, 29 patchouli variant plants were obtained, which were divided into seven morphological types, namely three-leaf whorls, heteromorphic leaves, deep-split leaves, narrow leaves, coiled leaves, undercoiled leaves and purple leaves. The contents of osmotic conditioning substances [soluble sugar, soluble protein and free proline (Pro)], antioxidant substances [malondialdehyde (MDA), peroxidase (POD), catalase (CAT)], pogostone and patchouli alcohol were compared and analyzed. According to the analysis results of the above determination indicators, 15 potential plants were finally screened, namely: stress-resistant plants with high effective components SY7 and ZY1; environmentally sensitive plants with high effective components SY15, SY18 and XY1; stress-resistant plants SY2, SY6, SY19, YY2, YY9 and XJY1; high active ingredient plants SY10 and SY17; “pogostone-type” patchouli plants SY3 and JY1. Among them, SY7 and ZY1 are new germplasms with double excellent characteristics, and the two “pogostone-type” patchouli plants have application value for solving the problems of the lack of authentic medicinal materials and the degradation of germplasm. In this study, patchouli variant plants bred by the ⁶⁰Co-γ ray irradiation mutagenesis method have the advantages of strong stress resistance and high active ingredients, which would provide mature methods and potential germplasm for patchouli mutagenesis breeding and new variety breeding.

The adsorption and desorption rates of nine cationic exchange resins on ergothioneine (EGT) were investigated to screen out the ion exchange resin suitable for the separation and purification of EGT from natural rubber serum (NRS) and determine the optimum process parameters. The results showed that the SA-2 cation exchange resin was the most suitable for the separation and purification of EGT from NRS, and the optimum parameters were as follows: pH of sample loading 3.0‒4.0, sample loading flow rate 2 BV/h, and eluted with 0.5% ammonium hydroxide at the flow rate of 1 BV/h. Furthermore, a higher sample loading concentration was more conducive to the adsorption capacity of resin. Under the conditions, the EGT elution rate could reach 97.83%. This research indicated that the SA-2 cation exchange resin is an ideal medium for the separation and purification of EGT from NRS, which would lay a theoretical foundation for the industrial production of EGT.

The intercropping of Mallotus peltatus under the forest helps to break the bottleneck of land use. It is of great significance to apply green nanotechnology to improve the benefits of its compound planting. In order to clarify the regulatory role of nano-iron in the intercropping of M. peltatus under the coconut forest, the annual seedling of M. peltatus was taken as the research object to carry out the cultivation experiment. We investigated the comprehensive effects of five concentrations of nano-iron treatments (CK: 0 mg/L, T₁: 25 mg/L, T₂: 50 mg/L, T₃: 75 mg/L, T₄: 100 mg/L) on the leaf growth, photosynthetic and chemical characteristics of M. peltatus. After the first nano-iron treatment, the leaf length, width and dry weight of M. peltatus in T₃ treatment were significantly higher than those in CK, while the leaf number in each treatment was significantly more than that in CK. Compared with CK, the chlorophyll content of M. peltatus treated with four nano-iron concentrations increased significantly by 14.96% (T₁), 16.18% (T₂), 17.91% (T₃) and 20.58% (T₄). As the concentration of nano-iron increased, the leaf net photosynthetic rate, transpiration rate, stomatal conductance, efficiency of primary conversion of light energy of PSⅡ, actual photochemical efficiency of PSⅡ and electron transport rate of M. peltatus overall increased. After the second nano-iron treatment, leaf length, width, dry weight and number of M. peltatus treated with T₁, T₃ and T₄ were significantly higher than those of CK. Compared with CK, the chlorophyll content of M. peltatus in each treatment significantly increased by 10.28% (T₁), 7.53% (T₂), 11.13% (T₃) and 11.41% (T₄). With the increase of nano-iron concentration, the leaf net photosynthetic rate, transpiration rate and stomatal conductance of M. peltatus increased significantly, but decreased when the concentration reached T₃ treatment. The potential activity of PSⅡ and efficiency of primary conversion of light energy of PSⅡ of M. peltatus also decreased significantly in T₃ treatment. After two treatments, the contents of flavone, fat and ash of M. peltatus increased significantly in T₁ treatment compared with CK. The contents of fat and ash decreased with the increase of nano-iron concentration. To sum up, nano-iron has a positive regulatory effect on the growth of M. peltatus under the coconut forest, but high concentration will inhibit its photosynthesis and growth. We recommend that the appropriate concentration is 25‒50 mg/L. This study could provide theoretical reference for the application of nano-iron in intercropping M. peltatus under the coconut forest.

The effects of different nitrogen forms on the growth, rhizosphere soil nutrients and soil enzyme activities of cassava variety Huanan 9 (SC9) were studied to provide theoretical basis for the scientific fertilization of cassava in Hunan Province. CK (no nitrogen fertilizer), T₁ (amide nitrogen-urea), T₂ (ammonium nitrogen-ammonium sulfate) and T₃ (nitrate nitrogen-calcium nitrate) were set in the study. The level of soil fertility was the same, and the application rate of nitrogen fertilizer was 180 kg/hm². Effects of different nitrogen forms on plant height, stem diameter, soil nutrients, soil enzyme activity, yield and quality of cassava were studied. Compared with CK, different nitrogen treatments improved plant height, stem diameter, yield and quality of cassava. T₂ had the highest plant height, stem diameter, yield, dry matter rate and starch content, which was significantly higher than that of CK by 13.51%, 32.24%, 61.72%, 6.44%, 19.86%. Nitrogen application changed the nutrient content of rhizosphere soil, and T₂ had the best effect on the nutrient content of cassava rhizosphere soil. The contents of soil organic matter and alkali-hydrolyzable nitrogen in T₂ were higher than those in the other treatments. The content of available potassium in T₂ was higher than that in other treatments at root formation stage and root expansion stage. Compared with CK, nitrogen application increased soil enzyme activity in cassava rhizosphere. With the passage of the growth period, urease activity increased gradually, sucrase activity decreased at first and then increased, catalase and nitrate reductase activity increased at first and then decreased. Among them, the soil sucrase activity in T₂ was the highest. Comprehensive analysis, in Hunan, the effects of different nitrogen forms on cassava growth and soil environment were different. Compared with CK, nitrogen application improved soil fertility, and then improved the growth of aboveground parts of cassava, thus improving the yield and quality of cassava. Among them, the application of ammonium nitrogen fertilizer is more beneficial to the growth and yield of cassava SC9.

The quality analysis of Chinese cherry fruit is beneficial to the selection and breeding of cherry varieties suitable for regional development. At the same time, it also lays a theoretical foundation for the protection of Chinese cherry germplasm resources. In this experiment, combining principal component analysis, correlation analysis and cluster analysis methods, 30 Chinese cherry fruits of different varieties (excellent lines) under the same cultivation conditions were selected for external and internal quality analysis. The results showed that there were significant differences in fruit quality among different varieties of Chinese cherry under the same cultivation conditions. The scores of comprehensive character evaluation ranked as C78, C6, C14, C34 and C32. Variety C20 (Manaohong) has excellent cultivation performance in some provinces in China, ranked 11th in this comprehensive evaluation. The 9 fruits intrinsic quality indexes had varying degrees of variation, with variation coefficients ranged from 11.27% to 36.32%. There was a correlation coefficient between the quality indicators, among which 12 were significantly correlated at 0.01 level and 17 were significantly correlated at 0.05 level. Principal component analysis of 13 quality traits showed that the cumulative contribution rate of the first 7 principal components was 88.196%, which could reflect the basic characteristics of quantitative traits. Cluster analysis with Euclidean method showed that 30 different Chinese cherry varieties (excellent lines) were preliminarily divided into 4 categories. The fruit quality analysis results obtained in this experiment could be used to explore the genetic variation map of cherry resources in China, and also be used as a reference for new varieties breeding.

In this paper, the seedlings of 27 inbred lines of bitter gourd with four leaves and one heart were used as materials. After pre-cultivated one day, the seedlings were subjected to 39 ℃ temperature stress. And the 27 germplasm resources were divided into three types: high heat resistance, medium heat resistance and heat sensitivity screened by the heat damage index (TDG) after 72 hours of high temperature stress. Among them, six inbred lines with different heat tolerance were selected to measure 12 morphological and physiological indexes subjected to 39 ℃ stress for 0 h and 48 h, respectively, including plant height (PH), stem diameter (SD), plant fresh matter (SFW) and dry matter (SDW) and leaf relative chlorophyll content (SPAD), electrical conductivity (REL), peroxidase activity (POD), catalase activity (CAT), superoxide dismutase activity (SOD), malondialdehyde content (MDA) ), proline content (Pro) and soluble sugar content (SS). The comprehensive evaluation values were obtained by the principal component analysis of heat resistance coefficients (α) of 12 morphological and physiological indexes to evaluate heat resistance of the seedlings. The mathematical model of heat resistanc evaluation was established by the stepwise regression analysis to obtain the heat resistance evaluation index system of bitter gourd. According to TDG, among the 27 bitter gourd inbred lines, three were heat-resistant, 18 were medium-heat-resistant and six were heat-sensitive. A mathematical evaluation model of heat tolerance of bitter gourd was established using the stepwise regression equation, which is Y=-0.426+0.049X₁-0.011X₂- 0.009X₃-0.018X₄. The established optimal regression equation was used to predict the heat resistance of the tested materials, and the predictive values were basically consistent with the comprehensive heat tolerance value. Therefore, the heat resistance coefficients of SFW(X₁), POD activity (X₂), CAT activity (X₃) and SS content (X₄) could rapidly and accurately estimate bitter gourd heat resistance and were suggested to be used as evaluation indexes for heat resistance of bitter gourd. In order to provide a basis for the breeding of new heat-resistant bitter gourd varieties in Hainan in summer season, the heat-resistant bitter gourd germplams were screened and a heat-resistant evaluation system was constructed.

In order to clarify the alleviating effect of heterologous double-root on coffee continuous cropping obstacle, the soil of the continuous cropping obstacle garden of coffee was used to cultivate Caffea liberica, No. 1 and C. canephora, Reyan No. 1 heterologous double-root grafting coffee seedling. The mechanism of heterologous double-root alleviating continuous cropping obstacle was clarified through different root separation ways, and the differences and synergies of heterologous double-root in alleviating continuous cropping obstacle were discussed. Compared with non-rhizosphere soil, the seedling quality index and plant biomass of heterologous double-root coffee or homologous double-root coffee decreased significantly after culturing in rhizosphere soil. After non-rhizosphere soil culture, there were no significant differences in the seedling quality index or plant biomass between heterologous double-root coffee and homologous double-root coffee. The seedling quality index, root biomass of C. liberica and C. canephora, and total plant biomass of heterologous double-root coffee were significantly higher than those of homogenous double-root coffee after rhizosphere soil culture. Continuous cropping obstacle inhibited the growth of coffee, but had more effect on homologous double-root coffee. Heterogenous double-root coffee alleviated the growth obstacle of continuous-cropping coffee by C. liberica roots. The seedlings quality of the heterologous double-root coffee separated root by nylon net was better than that of root undivided or separated root by double pot under continuous cropping, and the root growth of C. canephora was the best in nylon net separation. Root allelochemicals of C. liberica promoted the root growth of C. canephora. There was no significant difference in the seedlings quality of heterologous double-root coffee between root undivided and separated root by double pot, and the C. liberica root growth of root undivided was worse than that of double pot separation. The root growth of C. canephora inhibited the root growth of C. liberica when the heterologous double-root were in contact with each other, but this inhibition was not related to the allelopathic substances in the C. canephora rhizosphere. The root growth of C. liberica had no significant difference in nylon net separation and double pot separation. There was no effect on the root growth of C. liberica with or without the allelopathic substances. of C. canephora. The root system of C. liberica alleviated the continuous cropping obstacle by reducing the inhibition of allelopathic environment and promoting the root growth of C. canephora by its allelopathic substances. The results would provide a theoretical basis for the application of heterologous double-root grafting in the field.

Rice (Oryza sativa L.) is an important food crop, and the normal germination of rice seeds is related to the growth and yield of the plant in the later period. The germination begins with water absorption by dry seeds and ends with cotyl elongation. Water transport within and between cells is highly selectively regulated by aquaporins (AQPs). The seeds of cereal are rich in starch. And the endogenous gibberellin can induce the synthesis of hydrolase such as α-amylase in the embryo and secrete them into the starchy endosperm to degrade starch into small molecules for seed germination. Studies have shown that only α-amylase can complete the degradation of starch in rice seeds. Nitric oxide (NO) is a signaling molecule that forms a variety of active nitrogen substances. It also participated in the signaling process of seed dormancy removal. NO donor plays a role in seed germination by enhancing amylase activity. NO donor can promote seed germination by improving the activity of amylase. Rice hybrid seeds of ‘BoⅡ you 767’ were used as experimental materials to investigate the effects of aquaporins (AQPs) and nitric oxide (NO) on the germination of rice seeds. In this study, NO synthesis inhibitors N-(G)-nitro-L-arginine methyl ester (L-NAME) and sodium tungstate (ST), sodium nitroprusside (SNP), an exogenous donor of NO, and mercury chloride (HgCl₂), an activity inhibitor of AQPs, were used to treat rice seeds. The changes of water absorption capacity, amylase activity and starch degradation rate during germination of rice seeds were determined in virtue of apparent analysis and index detection. The results showed that the water absorption capacity, amylase activity and germination rate decreased in the rice seeds treated with 90 mg/L HgCl₂, while the starch content remained high, and the growth of radicle and germ was inhibited. However, NO exogenous donor SNP could reverse the effect of HgCl₂. And the effect of NO synthesis inhibitors L-NAME (15 mmol/L) and ST (80 µmol/L) on the germination of rice seeds was similar to that of HgCl₂. The results indicated that AQPs could induce water uptake, stimulate amylase, accelerate starch degradation and promote seed germination in the early germinating stage of rice seeds through NO. The study would lay a theoretical foundation for improving rice yield.

In August 2022, we found Phyllanthus urinaria with yellows and witches’-broom symptoms, respectively, in areca yellows disease garden in Wenchang city, Hainan province, which were phytoplasma infection. In order to clarify the taxonomic status of the phytoplasma strain in the yellows leaves and witches’-broom of P. urinaria. In this study, we cloned the 16S rDNA gene and ribosomal protein (rp) gene, and analyzed the gene sequence consistency, phylogenetic tree and virtual RFLP. The results showed that the 16S rDNA fragment 1246 bp and rp gene 1212 bp were cloned of P. urinaria yellows phytoplasma, the 16S rDNA fragment 1827 bp and rp gene 1240 bp were cloned of P. urinaria witches’-broom phytoplasma. The gene sequence consistency showed that the 16S rDNA gene sequence of the P. urinaria yellows phytoplasma and the P. urinaria witches’-broom phytoplasma was more than 98% consistent with the phytoplasma of 16SrⅠ group, and 100% consistent with the 16S rDNA sequence of areca yellows phytoplasma Hainan strain; the consistency of them in rp gene sequences was more than 99% to those of the rpⅠ group. The phylogenetic tree analysis showed that the 16S rDNA genes of P. urinaria yellows phytoplasma and P. urinaria witches’-broom phytoplasma were clustered in a large branch with those of aster yellows phytoplasma group (16SrⅠ), and clustered in the same small branch with those of areca yellows phytoplasma of 16SrⅠ-B subgroup, with the close genetic relationship; in the phylogenetic tree of rp gene, they were clustered in a large branch with the aster yellows phytoplasma group (rpⅠ), and clustered in the same small branch with those of aster yellows phytoplasma of rpⅠ-B subgroup, with the close genetic relationship. The virtual RFLP analysis showed that the RFLP map obtained by the 16S rDNA gene of the P. urinaria yellows phytoplasma and P. urinaria witches’-broom phytoplasma was the same as the reference map of the onion yellows phytoplasma of 16SrⅠ-B, and the similarity coefficient was 1.00. In summary, the P. urinaria yellows phytoplasma and the P. urinaria witches’-broom phytoplasma belong to 16SrⅠ-B subgroup in classification. The results of this study could provide a theoretical basis for the prevention and control of areca palm yellow disease by eradicating its intermediate host.

Papaya is an economically important tropical fruit. Papaya ringspot virus (PRSV) is an important virus disease of papaya, often causing significant yield losses and quality deterioration. Since the introduction of the first transgenic papaya in 1998, PDR-based breeding strategies for disease resistance have been successfully applied. The contradiction between disease resistance based on sequence homology and increased virus genetic diversity became a new challenge for papaya breeding. In this study, we propose to use RNAi strategies aim at nuclear inclusion b gene (Nib) to obtain broad-spectrum resistance to PRSV papaya. With optimized embryo callus generation-Agrobatium meidated transformation-shoot regeneration, 52 shoots were obtained after resistance screening and a total of 24 transgenic positive shoots were obtained by specific PCR screening for the T₀ generation. In the T₀ generation field natural disease test, the transgenic papaya strains were significantly more resistant to disease than the non-transgenic control, with NibB5-2 having the best resistance in the field. Molecular charaterization of the insertion site of Nib5-2 was located at position 1976766 on chromosome 2 supercontig_30 by hiTAIL-PCR method. Green house inoculation test of NibB5-2 T1 generation, there was no virus accumulation and no disease symptoms, confirmed the resistance. Our resulst reveal that RNAi silcencing the Nib gene enhance the papaya virus resistance, meanwhile enriched the candidated genes for virus resistance breeding.

Wampee [Clausena lansium (Lour.) Skeels] is a species of Rutaceae family and native to Southern China, which contains a large number of bioactive compounds that are beneficial to human health. However, because of the thin pericarp and soft pulp, wampee fruit is susceptible to the mechanical damage and the quality deterioration symptoms of fruit rot, pericarp browning and storage characteristic loss, and thus reducing the commercial value and edible value of harvested wampee fruit. Therefore, it is necessary to develop a safe and environmentally friendly postharvest storage technology for enhancing the storage behavior and quality, and prolonging storage time of harvested wampee fruit. Oxyresveratrol (OXY) is a naturally active product, with the efficacies of anti-browning, anti-oxidation, antibacterial, anti-inflammatory and antiviral. OXY has been studied more in the field of medicinal health care, but less in the field of food preservation. However, there are no reports on increasing the storage behavior and postharvest quality of wampee fruit by the usage of exogenous OXY. The study was aimed to study the effects of exogenous OXY treatment on the preservation of harvested wampee fruit. The fruit of wampee cv. Jixin was used as the experiment material, and the wampee fruit was treated by OXY solution with concentration of 0.2 g/L and distilled water (CK) for 30 min, separately. Then, the fruit was air-dried and packaged (50 fruits per bag), and stored at relative humidity 85% and temperature (25±1)℃ for 10 days. The changes of related indices of the storage behavior and postharvest quality in wampee fruit were observed and measured every two days. Compared to CK, OXY treatment could delay the increments of pericarp cell membrane permeability, browning degree and browning index, and maintain a higher commercially acceptable fruit rate but a lower weight loss percentage of harvested wampee fruit. Furthermore, OXY treatment might keep the higher values of L^* and hue angle, a higher total phenolics content, but the lower activities of phenolases such as peroxidase and polyphenol oxidase in pericarp of harvested wampee fruit. Moreover, OXY treatment could retain the higher contents of total soluble solids, vitamin C, titratable acidity, sucrose and total soluble sugar in pulp of harvested wampee fruit. Therefore, the treatment of exogenous OXY could effectively enhance the storage behavior, and retain the pericarp appearance quality and pulp nutritional quality, and thus prolong the storage time in harvested wampee fruit.

Colletotrichum siamense is the main pathogen of anthracnose in many crops in tropical and subtropical regions. SSK1 is a response regulator protein of the two-component system. Studies have shown that SSK1 in pathogenic fungi is related to the morphogenesis, stress response, drug resistance and pathogenicity of pathogens, but SSK1 homologues have distinct functions in different fungi. In order to understand the function of CsSSK1 in C. siamense, the CsSSK1 gene deletion mutant ΔCsSSK1 and the complement strain ΔCsSSK1 (CsSSK1) were constructed and phenotypically observed. The results showed that the deletion mutant ΔCsSSK1 showed slightly retarded mycelial growth, shorter conidia, lower sporulation and conidial germination rate. ΔCsSSK1 significantly increased the sensitivity of C. siamense to NaCl, sorbitol, sucrose, glucose and Congo red, and the sensitivity to fluconazole and tebuconazole, but decreased the sensitivity to fludioxonil. The pathogenicity of ΔCsSSK1 was significantly reduced. The results showed that CsSSK1 gene was involved in the regulation of C. siamense morphogenesis, response to salt stress, osmotic stress, Congo red stress and fungicide stress, affecting the pathogenicity of C. siamense. The results would lay a foundation for further understanding the function of CsSSK1 gene in C. siamense and analyzing the molecular mechanism of pathogenic fungi response to stress.

In this study, 75% ethanol solution was used to prepare the total extracts of arecanut nut (ANE). Then different fractions of the extracts were prepared by fractionating with petroleum ether (PE-ANE), ethyl acetate (EAC-ANE), n-butanol (BU-ANE) and water (W-ANE) in turn. The inhibition of hypertension from ANE was determined by angiotensin converting enzyme (ACE) activity inhibition assay in vitro. The inhibitory was evaluated with the fraction displayingthe best ACE inhibitory activity by the enzyme kinetic method. In addition, the contents of total polyphenols, total sugar and total protein in each fraction of ANE were determined. The correlation between the contents of the compositions and ACE inhibitory activities was analyzed. Finally, phenoliccomponents in the four fractions were analyzed. The results showed that all the fractions of ANE at different polar parts exhibited ACE inhibitory activity, and EAC-ANE displayed the best. Enzyme kinetics tests showed that the inhibitory effect of EAC-ANE from tender areca on ACE was a mixed type of competitive inhibition and non-competitive inhibition. The correlation analysis showed that the IC₅₀ value of the ACE inhibitory activity of each polar part of ANE was significantly negatively correlated with the content of polyphenols and total sugar. And the absolute value of the correlation coefficient between the IC₅₀ value of ACE inhibitory activity and the polyphenol content reached a very strong correlation (r=‒0.912). And a variety of polyphenol components such as catechin, L-epicatechin, procyanidin B₂, protocatechuic acid, and quercetin were identified in the four different polar parts, and the content of polyphenol components in EAC-ANE was the highest. In conclusion, ANE has a certain blood pressure lowering potential, and the ethyl acetate extraction site is the best, and the polyphenol content has a strong correlation with the ACE inhibitory activity of each extract. It can be preliminarily inferred that polyphenols may be the main substances that inhibit the activity of ACE in ANE.

In 2022, a stiff fruit disease was found on seedless litchi in Hainan, which was obviously different from the common litchi diseases in Hainan, such as anthracnose and acid rot. It mainly damaged young fruits. There was no significant change in the appearance of young fruits when the disease occurred. When the fruit was broad bean, the outer peel of the diseased fruit became darker, and the inner peel became irregularly brown after dissection. The fruit no longer expanded, forming fleshless stiff fruit, which was easy to cause serious economic losses. In this study, the pathogen of the disease was isolated, identified, invasion way and rapid detection techniques were studied. The pathogen was identified as Fusarium pernambucanum by morphological identification, ITS, RPB2 and TEF1 gene sequence analysis. The pericarp of seedless litchi fruit at young fruit stage was susceptible to pathogen invasion after being damaged by farming operations, wind, piercing-sucking insects, while the fruit surface was not diseased without wounds. The main invasion period of the pathogen was 3.2-4.8 mm in the longitudinal direction of the fruit. After the fruit was bigger than 9.8 mm, the probability of pathogen invasion gradually decreased. Based on the TUB gene sequence, the specific primers for rapid detection of F. pernambucanum were obtained, and a rapid and efficient molecular detection method based on ordinary PCR was constructed. The detection method is sensitive and efficient, and would provide support for early diagnosis and prevention of seedless litchi stiff fruit disease.

Five sweet potato cultivars with significant differences in germination, Jixu 23, Yanshu 25, Red Banana, Taizhong No. 6 and Xinxiang, were used as the test materials. During the storage period, samples were taken regularly to analyze the changes of endogenous hormones and carbohydrate metabolism in the storage roots. Storage roots after storage were planted for seedlings in small arch sheds and investigated. The results showed that Jixu 23, Yanshu 25 and Red Banana germinated earlier, and the number of seedlings picked was significantly more than that of Taizhong 6 and Xinxiang. At the end of storage and before seeding, the starch content and amylopectin content of storage roots in Jixu 23, Yanshu 25 and Red Banana were significantly higher than those of Taizhong No. 6 and Xinxiang, Jixu 23, Yanshu 25 and Red Banana. Higher content of amylopectin and amylopectin was mainly due to the smaller decrease during storage. The total amylase and α-amylase activity of storage roots in Jixu 23, Yanshu 25 and Red Banana were significantly higher than that of Taizhong No. 6 and Xinxiang, and the α-amylase activity of storage roots in Jixu 23, Yanshu 25 and Red Banana were higher than that of Jixu 23, Yanshu 25 and Red Banana. This is mainly due to the larger increase during storage. At the end of storage and before seeding, compared with Taizhong No. 6 and Xinxiang, Jixu 23, Yanshu 25 and Red Banana had higher GA content, lower IAA content, and higher GA/ABA and ZR/IAA of storage roots. That is, at the end of storage and before seeding, high starch and amylopectin content, high α-amylase activity, high endogenous GA content, and low IAA content in storage roots are physiological indicators of good germination.

Camellia oleifera is a unique oil plant of Theaceae, which has important ornamental value and economic value. With the intensive planting of Camellia, many diseases and pests occur. In addition, the delayed breeding of improved varieties seriously restricts the development of the Camellia industry. INDETERMINATE DOMAIN (IDD) family is a kind of conservative transcription factors in higher plants, which regulate the basic immune response of plants by mediating plant endogenous hormones. In order to identify the members of IDD gene family in C. oleifera, 29 members of CoIDD gene family were identified through the conserved domain of IDD gene family with reference to the whole genome information of C. oleifera, and further clarified the structure, physical and chemical properties, phylogenetic relationship, and sub cell localization of each gene. The CoIDD4 gene homologous to AtIDD4/5/6 was cloned by RT-PCR, and its physicochemical properties, expression mode and nuclear localization signal were clarified. At the same time, the types of cis acting elements in its promoter region were analyzed. The results showed that 29 CoIDD gene family members were divided into 4 subgroups, with average hydrophilicity coefficients less than 0, belonging to hydrophilic proteins, and subcellular localization was located in the nucleus; The full-length ORF frame cloned into CoIDD4 gene contained 1620 bp base and encoded 539 amino acids, which were mainly expressed in leaf and flower organs; The cis acting elements in the promoter region of the gene were mainly involved in light response and plant hormone response elements. In conclusion, this study identified 29 IDD gene family members in C. oleifera, among which CoIDD4 gene was closely related to AtIDD4/5/6. It is speculated that CoIDD4 gene may be involved in the process of hormone signal transduction and basic immune response regulation of C. oleifera, which would provide a theoretical basis for the functional analysis of IDD transcription factors in C. oleifera and provide a reference basis for the selection and molecular breeding of superior resistant varieties of C. oleifera.

This study was conducted to explore the cumulative demand of nitrogen, phosphorus and potassium in disease-free sugarcane original seedlings, and provide reference for the nutrient management in the process of field propagation of disease-free sugarcane original seedlings. The growth of the disease-free sugarcane original seedlings of Zhongtang No. 1 in 2020 and 2021 was investigated, and the biomass and contents of nitrogen, phosphorus and potassium in roots, stems and leaves at various growth stages were determined for further analysis of the accumulation, phase absorption and daily absorption rate of nitrogen, phosphorus and potassium. It took 6 to 7 months for disease-free sugarcane original seedlings to reach 15 stem nodes from temporary planting of seedlings to the best harvest of seed canes. From July, August to late September (stem 1 to 2), the growth of sugarcane stems was the fastest. The cumulative increase of dry matter was the fastest in stem 4 (late October to late November), and this is the key stage of biomass accumulation. During the whole growth period of the disease-free sugarcane original seedlings, the content and accumulation of each element from high to low were potassium > nitrogen > phosphorus. Among the organs of roots, stems and leaves, leaves and stems always had higher nitrogen, phosphorus and potassium contents. The accumulation of nitrogen, phosphorus and potassium was mainly stored in the leaves before the stem elongation stage 1, and then mainly stored in the stems. The nutrient uptake rates of nitrogen, phosphorus and potassium at the seedling stage and tillering stage was 24.84%, 26.18% and 27.74%, respectively, and it was 55.54%, 58.61% and 52.30% at the stem 1 to 3 (late July to late October), while 19.62%, 15.20% and 19.96% during stem 4 and 5 (late October to late December). Reasonable fertilization can be carried out according to the phase absorption of each element, thereby improving the quality and economic benefits of disease-free sugarcane seedlings production. The demands of nitrogen, phosphorus and potassium in the breeding process of disease-free sugarcane original seedlings were clarified, which would provide a reference for the scientific and reasonable fertilization in large-scale field propagation of disease-free sugarcane original seedlings in the future, and improving the efficiency of the propagation and nutrient utilization of disease-free original seedlings.

Virus disease is one of the most serious diseases in tomato production in Hainan, China. The small RNA deep sequencing data of tomato virome in Hainan revealed the presence of Southern tomato virus (STV) in samples from several regions, and a single STV infected sample was found. RT-PCR screening of 987 field samples with virus-like symptoms collected from 2015 to 2021, was carried out to determine the distribution of STV in Hainan province. Results indicated that STV was detected in 142 samples from nine regions, STV had existed in Hainan tomatoes as early as 2015, STV detection rate increased from 8.82% in 2015 to 22.45% in 2021, showing an upward trend year by year. The complete genome length of four isolates amplified using RT-PCR and RACE was identical, each consisting of 3446 nt. Two partially overlapping open reading frames (ORFs) presented in the positive-sense RNA strand, the 5′-proximal ORF (position 147-1280 nt) encoded a 377 amino acid (aa) peptide representing a potential coat protein (p42), the second ORF (position 1048-3336 nt) contained typical motifs for an RNA-dependent RNA polymerase (762 aa). The length of 5′ untranslated region (UTR) and 3′ UTR was 146 nt and 110 nt respectively. Paired comparison showed that the nucleotide similarity among four STV isolates was 99.86%-100.00%, the nucleotide similarities with other STV isolates available in GenBank were 98.45%-99.94%. In phylogenetic trees based on the complete genome of STV, eighty STV isolates were obviously divided into two groups (Group Ⅰ and Group Ⅱ). Group Ⅰ included Asian, American, European and African isolates. In group Ⅱ, except for one Asian isolate, the others were European isolates, and four Hainan isolates were divided into group Ⅰ. The grouping of STV isolates was related to geographical location, may not be related to the host. The regions with high genomic sequence variability between Hainan isolates and group Ⅰ isolates were 881-1061 nt and 1521-1721 nt, and the regions with high genomic sequence variability between Hainan isolate and group Ⅱ isolate were 2041-2241 nt and 2761-2921 nt. No recombination events were found between STV isolates. This is the first report of STV in Hainan Province. The findings of this study would provide an important basis for understanding the distribution and occurrence trends of STV in Hainan province and for the development of effective surveillance and control measure.

Rubber particles are important components in latex, and have important effects on latex stability, rubber biosynthesis and processing properties. However, the difference of rubber particle size and distribution among different germplasms and the annual changes have not been systematically studied. In this study, 486 wild and cultivated Hevea germplasm planted in National Rubber Germplasm Respository were selected, and the latex were collected monthly during the tapping period from 2020 to 2021. The average diameter (Da), intermediate diameter (Di), intermediate diameter/average diameter (Di/Da), particle size≤0.259 μm frequency and particle size≤0.197 μm frequency of rubber particles were analyzed and studied. Da varied from 0.313 μm to 0.439 μm, and the coefficient of variation (CV) was 0.008-0.206. Di varied 0.209-0.366 μm, and the CV was 0.009-0.235. Di/Da varied 58.3%-84.9%, and the CV was 0.015-0.123. particle size≤0.259 μm frequency varied 31.1%-61.8%, and the CV was 0.013-0.322; particle size≤0.197 μm frequency varied 17.6%-46.4%, and the CV was 0.018-0.588. The five indexes showed significant differences among germplasm, which were suitable to be latex characteristic index. The correlation analysis of the five indexes showed that the correlation coefficient of Di and Da was 0.781; The correlation coefficient of particle size≤0.259 μm frequency and particle size≤0.197 μm frequency was 0.976; The correlation between Di and Di/Da was higher than that of Da, and the correlation coefficient reached 0.814. Di was also more correlated with particle size≤0.259 μm frequency and particle size≤0.197 μm frequency than Da, and the correlation coefficient reached 0.520 and 0.632, indicating that Di had a stronger statistical significance. Annual changes of Da, Di and Di/Da showed some difference. Da in June, July, August, October and December was not significant, and September and November were lower than other months. Di was not significantly different in June, July, August, September, November and December, and just a little lower in October. Di/Da had no significant difference in June, August and September, increased in November and December, but declined obviously in July and October. Da, Di, Di/Da, ≤0.259 μm frequency, ≤0.197 μm frequency in each month were all significantly correlated with the annual average. However, correlation coefficient were higher between alternate monthly measurements (June, August, October; July, September, November; August, October, December) and the annual average, reaching more than 0.850. That can be used for future rubber particle size testing.

Cordyceps chanhua is an important Chinese traditional medicine and food, that has important application value in the development of green functional food and new resource drugs. Taking one wild fungi Chanhua collected from Qujing of Yunnan province as the experimental material, the biological characteristics and artificial cultivation conditions were studied for the purpose of domestication and cultivation. Based on the morphological anatomy and molecular phylogenetic analysis, a wild ascomycetes was identified as C. chanhua. The biological characteristics and domestication of C. chanhua strain were studied by single factor experiments and orthogonal tests. The result showed that the branch stalk of C. chanhua was orange yellow or yellow white, (8.0-28.0)mm×(1.5-3.0)mm, and the conidia was oblong, (4.0-8.5)µm×(1.5-3.5)µm. The optimum temperature for the mycelial growth was 24 ℃, the optimum pH value was 6, the carbon source, nitrogen source and mineral salt was sucrose, yeast powder and magnesium sulfate respectively. The results of orthogonal test based on three factors under the optimum pH value and temperature showed that carbon source had the greatest impact on the mycelial growth, followed by nitrogen source and mineral salt, with range 1.21, 0.39 and 0.13 respectively. Therefore, the optimal combination of factors for the mycelial growth of C. chanhua was sucrose 20 g/L, yeast powder 2 g/L and magnesium sulfate 2 g/L. The artificial cultivation of C. chanhua utilized the 1∶1 mixed medium of wheat and rice, and the harvest cycle of fruiting body was about 40-45 days, and the average dry weight of each cultivated Chanhua was about 9.56 g. The external morphological characteristics of artificially harvested C. chanhua were significantly different from those of wild fruiting body. The fruiting body was yellowish to light yellow, with few branches, 1.5-5.0 cm in length, 0.3-0.8 cm in width and 0.1-0.2 cm in depth. The sporangium bundles were covered with dirty white flocculent or powdery conidia. The screening of excellent strains and optimal culture conditions of C. chanhua would provide a theoretical basis for its study on the diversity of germplasm resources, protection and utilization.

Amomum tsao-ko (AT) is a medicinal and food homologous crop rich in polyphenols and flavonoids. The germplasm of AT is relatively mixed, and it is urgent to carry out research on AT germplasm resources and screening of high-quality AT seed sources. This study aimed to screen and evaluate the content of polyphenols and flavonoids and antioxidant activities of laxative active components of AT resources, and to explore the possible factors of component accumulation. In this study, a total of 57 samples were collected in Laos, Myanmar, Sichuan, Guangxi and Yunnan in China, and the polyphenol content and flavonoid content of AT aqueous extract were determined by forinphenol method and NaNO₂-Al(NO₃)₃-NaOH colorimetric method, and the DPPH radical scavenging ability of AT aqueous extract was detected. The correlation between polyphenol and flavonoid content, DPPH radical scavenging capacity and geographic factors was analyzed. The results showed that the content of polyphenols and flavonoids in spindle-shaped AT resources was higher than that of oval fruit and round fruit, and the content of flavonoids in AT resources abroad and Nujiang was higher than that in other regions (outside the province, western Yunnan, southwest Yunnan, Wenshan and Honghe). The content of AT polyphenols and flavonoids was significantly positively correlated with DPPH radical scavenging capacity and altitude (P<0.05), and negatively correlated with longitude (P<0.05) and latitude (P>0.05), so it was speculated that the accumulation of AT polyphenols and flavonoids may be related to temperature, light, ultraviolet rays and soil moisture. Finally, according to polyphenols, flavonoids, the classification standards were formulated, and the AT resources were divided into three grades, which would provide an analysis method for the establishment of the AT quality grade evaluation system. The excellent AT resources were screened by this method as Nujiang samples GS-3 and GS-10 and foreign samples MDL-1 and MGK-2. This study would provide a scientific basis for the investigation and collection of AT, as well as the study of origin and evolution, and also lay a solid foundation for the utilization of AT resources and the development of industry in the future.

The effects of water management and foliar spraying of exogenous plant hormone ethylene (ETH) on the accumulation of rhizosphere iron membrane, cadmium (Cd) and health risk index of rice were studied. Through the potting test, two concentrations (50 μmol/L and 100 μmol/L) ethylene (ETH) were sprayed three times at the jointing stage, the flowering stage and the grouting stage, and the water management modes of continuous flooding (CF) and interval flooding (IF) were adopted. Compared with the IF water management mode, the storage morphology of Cd in the soil was changed in the CF water management mode, and the soluble Cd was reduced from 36% to 30%, and the reducing state Cd was increased from 30% to 40%. Compared with the IF water management mode, the Fe and Cd content in the rice root surface iron film were significantly increased in the CF water management mode, and the exogenous spraying of ETH also significantly increased the Fe and Cd content in the iron film under the two water management modes, up to 50.59% and 58.06%. Compared with the IF water management mode, the Cd content in rice roots, leaves, brown rice and polished rice decreased significantly under the CF water management mode. The external spraying of ETH was also conducive to reducing the cadmium content of rice under the two water management modes, among which the Cd content in polished rice under CF+50ETH treatment was the lowest, and the Cd content in polished rice decreased from 0.68 mg/kg to 0.45 mg/kg, a decrease of 33.82% compared with CF treatment. Exogenous spraying of ETH significantly reduced the transport coefficients of Cd from rhizome and stem-grain under the two water management modes, and the transport coefficients were the lowest under CF+50ETH treatment, which was reduced by 55.17% and 23.81% respectively compared with CF treatment. CF water management mode and spray ETH treatment have a good effect on reducing the health risk index of rice Cd. It can be seen that CF water management mode and exogenous spraying of ETH have certain application prospects for reducing the accumulation of Cd in rice.

Anthocyanins, also called anthocyans, are a group of plant secondary metabolites of flavonoid derivatives. Anthocyanins play an important role in mediating plant stress responses. However, whether anthocyanins are also involved in regulating phyllosphere bacterial communities remains unknown. To evaluate the differences of phyllosphere bacterial communities in plants with different anthocyanin contents, this study analyzed the phyllosphere bacterial communities of two cultivars of elephant grass with contrasting anthocyanins content, Pennisetum purpureum cv. Purple (Purple) with a high amount of anthocyanins and P. purpureum cv. Mott (Mott) with relatively low anthocyanins. The anthocyanins content determination results showed that the anthocyanins content in Purple leaves was nearly 20 times of that in Mott leaves. High throughput sequencing of 16S rRNA and analysis of the microbiome community indicated that though alpha diversity was not significantly changed, the bacterial communities of Purple was significantly different from that of Mott. In Purple, the relative abundance of endopphytic Proteobacteria and Bacteroidetes, and epiphytic Deinococus-Thermus were significantly increased, whereas epiphytic Bacteroidetes and Firmicutes were significantly decreased. The composition of microbiomes (ANCOM) at the OTU level, the relative abundance analysis at the genus level and correlation analysis between epiphytes and anthocyanins showed that the relative abundance of Methylobacterium, Unclassified Methylobacteriaceae and Deinococcus, which showed a significant positive correlation with anthocyanins content, were significantly increased in the episphere of Purple. In summary, the phyllosphere bacterial communities were significantly different between Purple and Mott. The findings from this work would provide new insights into the understanding of the superior forage value of P. purpureum cv. Purple, and lay a foundation to further investigate the mechanism of how plant secondary metabolism products regulate phylloshpere microorganisms.

In order to explore the effects of nitrogen fertilizer application rate and planting density on the source-sink relationship and yield of sweet potato during ridge-sealing period, and to improve the cultivation techniques of sweet potato in Hainan, a field experiment was carried out from 2019 to 2020. The fresh-eating sweet potato variety Gaoxi14 was used as the test material, and three planting densities were set up, namely 47 600 plants/hm² (D₁), 71, 400 plants/hm² (D₂) and 142 900 plants/hm² (D₃). Four nitrogen application rates (0 kg/hm² (N₀), 60 kg/hm² (N₁), 120 kg/hm² (N₂), 180 kg/hm² (N₃) were designed in a double-factor split plot design with planting density as the main plot and nitrogen application rate as the subplot to study the effects of different planting densities and nitrogen application rates on photosynthetic characteristics, the relative chlorophyll content (SPAD), stem and leaf growth, dry matter accumulation and distribution in source and sink, tuber characteristics in ridge-sealing period, yield and its components and commodity in harvest period of Gaoxi14. Under the same planting density, the net photosynthetic rate (P_n), fresh weight of stem and leaf, number of branches, longest vine length, number of tubers per plant and single tuber weight of commercial sweet potato increased first and then decreased with the increase of nitrogen application rate, and reached the maximum at N₁ treatment. The yield of sweet potato increased first and then decreased with the increase of nitrogen application rate, and reached the maximum under N₂ treatment, which was 32.0% higher than that under N₀ treatment, but there was no significant difference between N₂ and N₁ treatments. Under the same nitrogen application rate, the dry matter distribution ratio of sweet potato roots increased first and then decreased with the increase of planting density. The D₂ treatment reached the maximum but there was no significant difference between D₂ and D₃ treatments. The root shoot ratio and yield increased significantly with the increase of planting density, and reached the maximum at D₃ treatment. The yield of D₃ was 30.9% and 24.1% higher than that of D₁ and D₂, respectively. The results of correlation analysis showed that the nitrogen application rate and planting density had significant effects on the dry matter accumulation and distribution of root tubers, while the planting density had a significant positive correlation with the yield of sweet potato at harvest stage, and the correlation coefficient was 0.704. Based on the results of this experiment, when the nitrogen application rate was 60 kg/hm² and the planting density was 142 900 plants/hm² (D₃N₁), the yield of Gaoxi 14 was the highest, reaching 30.1 t/hm², and the corresponding potato commodity rate was 94.3%, which was the best among all treatments.

Phenotypic traits are the basis of breeding, which can reflect the genetic variation of species to a certain extent. Exploring the phenotypic diversity of Hibiscus rosa-sinensis cultivar can provide reference for the utilization of germplasm resources and the breeding of new varieties. In this study, 39 H. rosa-sinensis cultivar resources were selected as the research object. Data of 25 phenotypic traits were collected and measured, including 9 quantitative traits and 16 qualitative traits. Diversity analysis, correlation analysis, cluster analysis, principal component analysis and comprehensive evaluation were carried out. The results of diversity analysis showed that there was abundant variation in the 39 H. rosa-sinensis cultivar resources resources, and the coefficient of variation of 9 quantitative traits ranged from 9.49 to 31.05, among which, the coefficient of variation of pedicel length was the largest, and the coefficient of variation of leaf length/width was the smallest; the index of diversity was 1.7592 to 2.0299, among which the index of style length was the highest, and edicel length diversity index was the lowest. The diversity index of 16 quality traits ranged from 0.3898 to 1.3203, among which the diversity index of flower heart and eye area was the highest, and the diversity index of flower pattern was the lowest. Correlation analysis showed that there were significant positive correlations between flower diameter and petal length, outermost petal morphology and petal secondary color, leaf length and leaf width, petal length and style length, flower diameter and style length, petal length and width, and flower diameter and petal width. There was a significant negative correlation between petal width and pattern, style length and pattern, leaf width and leaf length-width ratio, and petal length and pattern. The cluster analysis showed that the 39 species could be divided into four groups at Euclidean distance of 20. The Ⅰ group contained 33 species resources, which were mainly characterized by the flower diameter between 11 cm and 17 cm, and could be further divided into two subgroups. The Ⅱ group contained two species, which were mainly characterized by double petals and small flower diameter between 10 cm and 11 cm. The Ⅲ group contained three species, which were characterized by single petals and large flower diameter, with the flower diameter between 18 cm and 20 cm. The Ⅳ group contained only one species. Principal component analysis showed that 9 principal components were extracted, the cumulative variance contribution rate of 79.85%. Through the calculation of main component of the 39 specie, the comprehensive score of Huo fenghuang was the highest, followed by Valentine's day, Moorea Hanging Garden and Fei jiangjun, while that of Yueyecaihong and Chocolate Cake was the lowest.

Anacardium occidentalie Linn is a typical tropical fruit tree, which is mainly planted in Yunnan and Hainan provinces of China. Cashew cultivation has important economic, social and ecological values. It is of great value to realize the strategy of rural revitalization in China, increase farmers' production and income, and achieve common prosperity. Cashews are very sensitive to low temperatures, and they will be severely damaged at 8 ℃and the growth will stop. Therefore, lowtemperature stress is an important abiotic stress that restricts cashew growth. CBF transcription factors play important roles in plant response to abiotic stresses such as low temperature, drought and salt. However, the role of CBF gene family in cashews has not been elucidated, and the expression pattern of this family in response to low temperature stress is unknown. In this study, in order to explore the basic characteristics of the CBF gene family in cashew nuts, six AoCBF gene family transcription factors were identified and obtained from the cashew transcriptome by bioinformatics methods, and the physical and chemical properties, protein structure, phylogeny, promoter action elements and expression patterns under low temperature induction were analyzed. The length of the six AoCBF proteins ranged from 189 to 334 aa, and the molecular weight of the proteins ranged from 21.31 to 37.89 kDa. The isoelectric points of the six AoCBF proteins were less than 7, indicating that the proteins were acidic. The proteins all contained an AP2/ERF domain. Motif analysis showed that there were five motifs in AoCBF genes, and the absence of different AoCBF gene motifs implied the absence of related functions. Phylogenetic tree analysis showed that the six AoCBF genes could be divided into two subgroups, A and B, in which group A contained one gene and group B only contained five genes. The analysis of homeotropic elements of promoter showed that AoCBF gene might be involved in the response to hormone and abiotic stress. Fluorescence quantitative expression analysis showed that all the six AoCBF genes responded to low temperature and cold stress to different degrees, indicating that AoCBF played a role in the biological process of cashew nut in response to low temperature stress. The results summarized the basic characteristics of the AoCBF gene family and accumulated basic data for further molecular resistance research and application of cashews AoCBF genes.

Phytosulfokine (PSK) is a small peptide hormone unique to higher plants, widely involved in biological processes such as plant growth and development, division and differentiation, biotic and abiotic stress. PSK receptor (PSKR) is a direct receptor for PSK and is crucial for PSK signal transduction. In the present study, HbPSKR2 was cloned from rubber tree by RT-PCR (reverse transcription-polymerase chain reaction), and its bioinformatics, gene expression pattern, interacted proteins screening and identification were also analyzed. Results showed that the open reading frame of HbPSKR2 had a total length of 3159 bp and encoded 1052 amino acids with molecular weight 114.84 kDa and theoretical isoelectric point 6.34. Domain analysis showed that HbPSKR2 was a typical trans-membrane protein. The first 640 amino acids were the antenna structures composed of leucine rich repeat (LRR), the 692 to 714 amino acids were transmembrane domains, and the 765 to 1052 amino acids were kinase domains. Multiple comparisons were conducted on the membrane kinase domain of HbPSKR2 and the membrane kinase domain of PSKR homologous proteins in Arabidopsis and rice. The results showed the existence of conserved sites such as ATP binding site, CaM binding site, Activation segment, GC Centre. Expression pattern analysis showed that HbPSKR2 was highly expressed in the cambium region of rubber tree. The expression level of HbPSKR2 was significantly increased at the early stage of coronatine (COR) treatment. Twelve candidate proteins interacted with HbPSKR2 were screened by yeast two hybrid technology, and the interaction between two protein kinases (HbPBL8 and HbPIX13) and HbPSKR2 was further verified by luciferase complementary imaging. The strong fluorescence signal was observed by co-transformation HbPSKR2-nLUC/HbPBL8-cLUC and HbPSKR2-nLUC/HbPIX13-cLUC into tobacco, suggesting the interaction between HbPSKR2-HbPBL8 and HbPSKR2- HbPIX13 in vivo. The cloning of HbPSKR2 and identification of HbPSKR2 interacted protein would provide new insights into the molecular mechanism of laticifer differentiation in rubber tree.