【Objective】The TIFY family, a plant-specific group of transcription factors, plays critical roles in regulating growth, development, and stress responses. This study aimed to clone TaTIFY11c-4A in wheat, validate its genetic effects, and provide a theoretical basis for high-yield molecular breeding of wheat.【Method】The wheat cultivar Hanxuan 10 was used to clone TaTIFY11c-4A and allelic variations were detected in germplasms. The tissue-specific expression patterns of TaTIFY11c-4A and its responses to various hormones and stresses were analyzed via quantitative real-time PCR (qRT-PCR). The subcellular localization of TaTIFY11c-4A was determined through transient expression in tobacco. A molecular marker targeting the polymorphic site in TaTIFY11c-4A was developed to assess the genotypes in the natural population, and association analysis was performed to evaluate the correlations between the genotypes and phenotypes. Additionally, the spatial and temporal distribution of different genotypes were analyzed. Synergistic effects of TaTIFY11c-4A and TaSRL1-4A haplotypes were explored to identify superior genotype.【Result】TaTIFY11c-4A was successfully cloned, comprising three exons and two introns, encoding a 198-amino acid protein with conserved TIFY and Jas domains. TaTIFY11c-4A is expressed in roots, root bases and leaves at the seedling stage, and highly expressed in roots and leaves at the booting stage. There are multiple cis-acting elements related to hormone responses, stress adaptation, and endosperm development in the promoter of TaTIFY11c-4A. Its expression responds to plant hormones (ABA, IAA, MeJA) and abiotic stresses (drought, high salinity, low and high temperature). A SNP (G/A) was identified in its promoter at -405 bp. A molecular marker was developed based on the SNP and association analysis revealed significant correlations between TaTIFY11c-4A alleles and plant height, thousand grain weight under multiple environments such as drought and high temperature, and root depth at tillering stage. Compared with genotype SNP-G, wheat germplasms carrying the SNP-A allele exhibited shorter plants, higher thousand grain weight, and shallower roots at tillering stage, and have been positively selected in the wheat breeding process. TaTIFY11c-4A-SNP-A and TaSRL1-4A-SNP-C genotypes synergistically reduced plant height and enhanced thousand grain weight.【Conclusion】TaTIFY11c-4A encodes a nuclear-localized JAZ protein. It is expressed in various tissues of wheat and involved in responses to ABA, IAA, MeJA, as well as abiotic stresses such as drought, extreme temperature, and high salinity. The TaTIFY11c-4A-SNP is associated with plant height and thousand grain weight under multiple environments, and root depth. SNP-A allele has been positively selected in the wheat breeding process. The superior genotypes and combinations of TaTIFY11c-4A and TaSRL1-4A provide genetic resources for breeding high-yield and stress-resistant wheat cultivars.
【Objective】Dwarf genes play a crucial role in wheat genetics and breeding. Different ecological zones and wheat varieties have varying requirements for plant height. Therefore, understanding the distribution pattern and characteristics of dwarf genes in Shanxi wheat, as well as identifying novel genetic loci related to plant height will contribute to wheat genetic improvement.【Method】Based on the accurate identification of plant height and component traits, a total of 11 known dwarfing gene types were genotyped in 306 Shanxi wheat samples and integrated with a 16K SNP chip to conduct genome-wide association analysis aimed at identifying new loci controlling plant height.【Result】With the exception of spike length, both of the plant height and component traits of Shanxi wheat exhibited a gradual decline over the years of breeding and the various compositional traits associated with plant height were influenced by distinct selection pressures. The distribution frequency of 11 dwarfing genes in Shanxi wheat from high to low was Rht12, Rht24, Rht8, Rht26, Rht13, Rht25, Rht2, Rht5, Rht4, Rht1, and Rht9, among which Rht1, Rht2, and Rht25 have not been found in landraces. Except for Rht2 and Rht25 is more widely distributed in irrigated cultivars than in dryland cultivars, the distribution of other dwarfing genes is relatively similar in dryland cultivars and irrigated cultivars. A total of 125 different dwarf genes combination were identified, of which the combination with the highest distribution frequency was Rht8+Rht12+Rht24. Combined with association analysis, a total of 26 stable genetic loci were identified to be distributed on 14 chromosomes including 1A, 2A, and 2B. Notably, eight loci such as QPH-6D, QPH-7A, and Q3rd IL-1D have not been reported yet. Among these, QPH-6D mainly reduced plant height by shortening the length of the third and fourth internodes by approximately 13.68 %, while QPH-7A reduced the plant height by 16.87 % via shortening the length of the second and third internodes.【Conclusion】The main dwarf genes in Shanxi wheat were mainly Rht12, Rht24, and Rht8. 26 stable genetic loci were located on chromosomes 1A, 2A, and 2B, among which eight loci such as QPH-6D, QPH-7A, and Q3rd IL-1D may be novel loci related to plant height.
【Objective】The purpose of this study was to analyze the quantitative trait loci (QTLs) related to stem nematode resistance in sweetpotato (Ipomoea batatas (L.) Lam.), lay a foundation for the fine mapping, cloning, and functional analysis of stem nematode resistance genes in sweetpotato. It also aimed to provide support for the study of the genetic mechanisms of stem nematode resistance, as well as the breeding of resistant varieties in sweetpotato.【Method】An F1 population of 212 progenies derived from a cross between the highly resistant cultivar Yushu 10 and the susceptible line Xin 24 was used. In this study, field-based natural infection assays were conducted to evaluate stem nematode resistance. QTL mapping was performed using composite interval mapping (CIM), and candidate genes within QTL confidence intervals were predicted. Additionally, genome-wide association studies (GWAS) were carried out using the rMVP software (a memory-efficient, visualization-enhanced, and parallel-accelerated R package). For further validation, the resistant cultivar Zhenghong 22 was artificially inoculated with D. destructor, and samples were collected at different post-inoculation time points. The expression patterns of five candidate genes (itf02g19880, itf02g20080, itf02g20100, itf13g18480 and itf13g18550) were analyzed via qRT-PCR.【Result】Three QTLs (qSNR02-1, qSNR02-2, and qSNR13-1) were identified, distributed on chromosomes 2 and 13. The phenotypic contribution rate of the individual QTL related to stem nematode resistance ranged from 9.6% to 11.7%. GWAS revealed one significantly associated locus with stem nematode resistance on chromosome 6. Based on the genomic annotation information, 36 candidate genes related to stem nematode resistance were predicted within the QTL confidence intervals, including members of the ABC transporter family, multidrug and toxic compound extrusion (MATE) efflux proteins, E3 ubiquitin ligases, and glutathione S-transferases, which are involved in defense mechanisms, post-translational modification, and stress response. qRT-PCR results showed that the expression patterns of the five candidate genes were significantly different. The expression level of itf02g20100 reached a peak at 3 days after inoculation, which was 6.2 times that of the control; the expression level of itf02g19880 increased sharply and reached the highest level at 0.5 days after inoculation, which was 43.2 times that of the control; the expression patterns of itf13g18480 and itf13g18550 were similar, and both reached a peak at 7 days after inoculation. This indicates that different candidate genes may play different regulatory roles in the defense response after Ditylenchus destructor infection.【Conclusion】Three QTLs related to stem nematode resistance in sweetpotato were identified, and 36 related candidate genes were screened out, which can be used for the subsequent cloning and functional study of genes related to stem nematode resistance in sweetpotato.
【Objective】This research has been conducted to clarify how exogenous melatonin interacts with stress responsive factors of abscisic acid (ABA) and hydrogen peroxide (H2O2) to enhance wheat drought resistance of wheat and explore the underlying mechanism.【Method】Wheat varieties Jimai 22 and Hengguan 35 were used as experimental materials, and six treatments were designed: normal water treatment (CK), exogenous melatonin treatment (MT), drought treatment (DS), melatonin treatment under drought stress (DS+MT), melatonin and ABA inhibitor fluoridone treatment under drought stress (DS+MT+Flu), and the treatment of melatonin and H2O2 scavenger diphenyl chloride iodide salt (DS+MT+DPI) under drought stress. The key physiological indicators of wheat roots and above-ground plants (chlorophyll, net photosynthetic rate (Pn), ABA, endogenous melatonin, malondialdehyde (MDA), superoxide anion (
【Objective】This study aimed to explore the effects of combining new bio-breeding insect-resistant varieties with dense-planting precision-controlled high-yield technology on maize yield and economic benefits, and to propose the optimal cultivation mode suitable for new bio-breeding insect-resistant varieties, so as to provide the theoretical basis for optimizing the high-yield and high-efficiency cultivation system of spring maize in the Xiliaohe Plain.【Method】Through a field trial in Tongliao, Inner Mongolia from 2023 to 2024, the experiment was conducted in a split-zone design, with cultivation mode as the main zone, setting up two modes of local traditional farmer mode (FP) and dense planting precision regulation mode (DPDI); varieties as the sub-zone, four maize varieties were used, namely, Dongdan 1331 (DD1331), Dongdan 1331K (DD1331K), Youdi 919 (YD919), Youdi 919HZ (YD919HZ). Then, the impact of varietal insect resistance traits on maize yield and economic benefits under different technical models were analyzed.【Result】During a two-year trial, the insect pests in the fields of insect-resistant varieties occurred lightly, with the insect plant rate of 6.80%-9.87%; the fields of conventional varieties occurred moderately or heavily, with the insect plant rate of 22.27%-36.31%. In 2023 (insect plant rate>30%), compared with conventional varieties (DD1331, YD919), the new insect-resistant varieties (DD1331K, YD919HZ) significantly increased thousand kernel weight, thus improving maize yield (0.84%-9.31%) and economic benefits (0.3%-13.3%), whereas in 2024, when the insect plant rate was about 23%, there was no significant difference in the number of thousand kernels and the number of grains between insect-resistant varieties, and there were no significant differences in ear grain number, thousand kernel weight and yield between conventional varieties. With increasing planting density, maize yield reached its maximum at 9.0×104 or 10.5×104 plants/hm2, which was significantly higher than that at 6.0×104 plants/hm2 density, by 13.54%-19.94% and 7.48%-21.01%, respectively. The two-year average yields of the dense planting precision regulated model were significantly higher than those of the traditional farmers' model, with yield increases ranging from 13.50% to 19.19% in 2023 and from 7.03% to 14.42% in 2024. Compared with the traditional farmers' model, the economic benefits of the dense planting precision regulation model were generally improved by 0.19×104-1.02×104 yuan/hm2.【Conclusion】Insect-resistant varieties (DD1331K, YD919HZ) significantly improved yield (up to 9.31%) and economic efficiency (up to 40.3%) in years of severe insect infestation (>30% of insect plants), but did not differ significantly from conventional varieties under low insect pressure. Through optimized density (9.0×104-10.5×104 plants/hm2) and precise management of water and fertilizer, DPDI increased yields by an average of 22.18% in two years and improved economic benefits by 0.57×104 yuan/hm2 compared with the conventional mode (FP); the core principle of DPDI was that insect resistant varieties could reduce the threat of pests, decrease yield losses, reduce the use of insecticides, and lower production input costs. By increasing the production capacity of maize populations through reasonable planting density and combining drip irrigation with water and fertilizer integration for precise regulation, the yield and income of maize could be increased. The synergistic application of insect-resistant varieties and DPDI model could achieve technological superposition and further improve the ability of high and stable yield.
【Objective】Rice bacterial leaf streak (BLS) is a quarantine-regulated bacterial disease in China caused by Xanthomonas oryzae pv. oryzicola (Xoc), which has severely threatened rice yield and grain quality, becoming one of the main diseases in rice production areas. This study aims to utilize high-quality actinomycete strains to lay a theoretical foundation for developing the products of microbial origin to mitigate crop diseases.【Method】Actinomycete strains were isolated and purified from rhizosphere soil samples of various plants using the serial dilution plating technique. The inhibition ability of different strains against Xoc was compared by measuring the diameter of the inhibition zone. The target strain with the best inhibition effect was selected for preservation and identified through polyphasic characterization integrating morphological traits, physiological-biochemical experiments, and multi-gene alignment analysis. The effects of antagonistic actinomycete on the physiological characteristics of Xoc were investigated by scanning electron microscopy, Fourier-transform infrared spectroscopy (FTIR), intracellular β-galactosidase leakage determination and SDS-PAGE gel electrophoresis. The greenhouse pot control effect test was carried out to study the actual benefit of controlling BLS. The growth-promoting characteristics of antagonistic actinomycete were analyzed by designated medium, and its effects on the growth and development of rice seedlings were investigated by watering growth-promoting experiments.【Result】A total of 80 actinomycete strains were isolated. Among them, strain Sv-6 exhibited the most potent antagonism against Xoc, with inhibition zone diameter of (44.87±0.26) mm. Based on the morphological characteristics and phylogenetic analysis, strain Sv-6 was identified as Streptomyces virginiae. After treatment with the culture filtrate of Sv-6 strain, Xoc cells swelled, shrunk and aggregated. At the same time, the material composition of the membrane surface changed, the permeability increased, and the protein expression decreased. The results of greenhouse pot experiments showed that the lesion inhibition rates of susceptible rice varieties Yongyou 15 and Xiangliangyou 900 were 57.98%-88.25% after being treated with strain Sv-6 culture fluid, which exhibited a good preventive effect on rice infected with Xoc. The growth-promoting characterization confirmed that strain Sv-6 exhibited siderophore production, inorganic phosphate solubilization, and IAA production. The growth-promoting irrigation experiments confirmed that strain Sv-6 enhanced the growth of rice seedlings, and the root length increased by 48.50% after treatment.【Conclusion】S. virginiae Sv-6 exhibits a good control effect on BLS, and has the potential to be developed into green biocontrol agent and microbial fertilizer.
【Objective】Citrus psorosis virus (CPsV) is a tripartite, negative-sense single-stranded RNA virus of the genus Ophiovirus in the family Aspiviridae, which can cause cracking of citrus trunks and even the death of the whole plant, seriously threatening the safety of the citrus industry. The construction of reverse genetics systems for negative-strand RNA viruses is challenging. This study aims to establish a full-length cDNA clone of CPsV genome and determine its infectivity, with the expectation of laying a foundation for research on its pathogenic mechanism and other aspects.【Method】The primers were designed using software Primer 5, and the total nucleic acid of CPsV-infected plants was used as a template for RT-PCR amplification of the three strands of CPsV, RNA1, RNA2 and RNA3, respectively. Based on the dual-expression vector pXT1, cDNA clones of three RNA strands were constructed by In-Fusion homologous recombination technology, which were verified by enzyme digestion and sequencing analysis. The cDNA clones of the three strands of CPsV were screened by the Nicotiana benthamiana inoculation system, and further inoculated into the herb host Gomphrena globosa by Agrobacterium-mediated injection, and then inoculated into different citrus varieties by vacuum infiltration to observe their symptoms and perform molecular detection.【Result】A total of two CPsV RNA1 full-length cDNA clones, two RNA2 full-length cDNA clones, and two RNA3 full-length cDNA clones were obtained, respectively. One full-length cDNA clone of RNA1, RNA2 and RNA3 was randomly selected and combined as a full-length cDNA clone of CPsV genome, eight RNA1, RNA2 and RNA3 cDNA clones were selected and inoculated on N. benthamiana through Agrobacterium-mediated inoculation and RT-PCR detection. Among the eight combinations, the positive rate of CPsV-122 was the highest (62.50%). Sequence analysis showed that CPsV-122 had the highest sequence identity with Spanish isolate P-121, and the corresponding sequence identities of RNA1, RNA2 and RNA3 were 98.06%, 97.10% and 99.32%, respectively. In a phylogenetic tree based on the amino acid sequence of coat protein, CPsV-122 and P-121 were clustered in the same clade and five isolates from China, Tunisia and Italy. CPsV-122 was inoculated by Agrobacterium-mediated inoculation to G. globosa, Citrus limon and C. paradise for symptom observation and RT-PCR test. The results showed that at 7 dpi, the positive rate of G. globosa was 16.67% (2/12), and at 25 dpi, the positive plants showed obvious reddish-brown blight, local necrosis of leaves and other CPsV infection symptoms. The RT-PCR results of C. paradise and C. limon were negative except for the positive control, but at 90 dpi, 13 out of 20 C. limon plants inoculated with CPsV-122 showed obvious CPsV infection symptoms such as dwarfing, yellowing, wilting shoots and shoot gelatinization, while no specific symptoms were observed in the empty vector group and the healthy control group.【Conclusion】CPsV-122 is a full-length cDNA clone of the CPsV genome, which can systematically infect G. globosa and cause typical CPsV infection symptoms on citrus, such as dwarfing and withering of shoots.
【Objective】The aim of this study was to investigate the effects of green manure combined with wheat straw returning application on grain yield and leaf photosynthetic characteristics of spring wheat (Triticum aestivum L.) under different nitrogen reduction levels, which could provide theoretical basis and technical support for establishing spring wheat multiple cropping with green manure saving and efficient production pattern.【Method】The experiment was conducted at the Wuwei Oasis Agricultural Experimental Station of Gansu Agricultural University in 2022 and 2023. The split-plot designed experiment was adopted. The main plot was designed with different returning materials at three levels, including green manure and wheat straw combined returning application (W-GS), green manure returning application alone (W-G), and fallowing after wheat harvesting (W-F). The split plot was designed with four nitrogen application levels, including conventional nitrogen application rate (N1, 225 kg N·hm-2), nitrogen application rate reduced about 15% (N2,190 kg N·hm-2), about 30% (N3,155 kg N·hm-2), and about 45% (N4, 120 kg N·hm-2). The chlorophyll value (SPAD value), photosynthetic characteristics and grain yield of the top expending leaf of spring wheat was measured, and the leaf water use efficiency and light energy utilization efficiency was analyzed.【Result】Negative effect of nitrogen reduced application was observed on the grain yield of spring wheat, however, this effect was compensated even the grain yield of spring wheat was increased by green manure combined with wheat straw returning application. With the same nitrogen application rate, compared with that of W-F, the grain yield of spring wheat under W-GS and W-G increased by 15.3% and 9.4%, respectively, and the grain yield of spring wheat with W-GS was increased by 5.4% than that of W-G. The grain yield of spring wheat under W-F was decreased by the decreasing of nitrogen application rate, while that of W-GS had no significant difference between N3 and N1. The grain yield under W-GSN3 was not reduced compared with that under W-GSN1 and W-FN1. The photosynthetic characteristics of spring wheat leaf with nitrogen reduced application rate was improved by green manure combined with wheat straw returning application. The SPAD value, net photosynthetic rate (Pn), stomatal conductance (Gs), transpiration rate (Tr) and leaf water use efficiency (LWUE) of spring wheat leaf under W-GS were significantly increased, respectively, compared with that of W-G and W-F under the same nitrogen application rate. With the decreasing of nitrogen application rate, the SPAD value, Pn, Gs, Tr and LWUE of spring wheat leaf under W-F was decreased significantly, however, there was no significant difference between N3 and N1 in W-GS. Comparison between combined treatments, there was no significant difference in photosynthetic characteristics of spring wheat under W-GSN3 compared with W-GSN1 and W-FN1. The light use efficiency (LUE) of spring wheat was significantly increased by 5.2% W-GS than that of W-F. The LUE of spring wheat with W-F decreased by the decreasing of nitrogen application rate, however, the LUE of spring wheat with W-GS was not significant difference between N3 and N1. There was no significant difference was observed in the LUE of spring wheat under W-GSN3 compared with that under W-GSN1 and W-FN1. The results of the path analysis indicated that, the grain yield of spring wheat was mainly determined by thousand kernel weight, which was affected by the regulation on net photosynthetic rate and transpiration rate via stomatal conductance of spring wheat leaf.【Conclusion】The green manure and wheat straw combined returning application mainly increased the thousand kernel weight of spring wheat by improving the photosynthetic characteristics of spring wheat leaf, and finally did not reduce the grain yield of spring wheat under 30% nitrogen reduced application rate. Therefore, the green manure and wheat straw combined returning application under nitrogen application rate of 155 kg·hm-2 was recommended as a nitrogen saving and efficient production pattern of spring wheat multiple cropping with green manure in arid oasis irrigation region.
【Objective】This paper aimed to investigate the characteristic of soil microorganisms and soil function under long-term strawberry continuous cropping and to clarify the effects of long-term strawberry continuous cropping on soil bacterial and fungal community structure and carbon, nitrogen and phosphorus metabolism gene abundance, so as to provide the scientific basis for improving the soil microecological balance and soil function of continuous cropping in the future.【Method】The real-time PCR, Miseq sequencing and high-throughput chip technologies were applied to determine soil bacteria, fungi and function under strawberry cultivated for 1, 3 and 10 year.【Result】The strawberry continuous cropping reduced the soil pH, but increased the soil nutrient content, in which the soil organic matter content increased from 21.2 g·kg-1 to 32.4 g·kg-1. The bacterial abundance in rhizosphere and bulk soil was increased and then decreased as the years of cultivation. The abundance of bulk soil fungi was similar to the trend of bacteria, but its abundance was significantly reduced in the rhizosphere, indicating that bacteria and fungi response differently to continuous cropping. Continuous cropping had no significant effect on bacterial diversity, but significantly reduced fungal diversity and significantly changed soil microbial composition. Based on UniFrac distance, it was found that the fungal community UniFrac distance (0.64-1.36) was much higher than the bacteria (0.028-0.111), indicating that the influence of continuous cropping on fungal community structure was higher than that of bacteria. Correlation analysis showed that bacterial community structure was significantly correlated with soil pH, while fungal community structure was significantly correlated with soil nutrient status (such as soil available P, alkali-hydrolysable, and soil organic matter). Long-term continuous cropping of strawberry changed the metabolic function gene abundance of soil carbon, nitrogen and phosphorus, which significantly reduced the soil carbon fixation gene accA, while the nitrogen fixation gene nifH and phosphorus metabolism related functions (phoD, phoX and pqqC genes) first increased and then decreased. The partial least squares path model (PLS-PM) analysis showed that the fungal community structure (abundance, diversity and composition) caused by long-term strawberry continuous cropping had a higher impact on soil carbon, nitrogen and phosphorus metabolism gene abundance than the bacterial community structure.【Conclusion】This study showed that soil function gene abundance changed caused by long-term strawberry continuous cropping was mainly caused by the changes of fungal community structure. Thus, the soil fungal community structure should be regulated to improve the health status of long-term continuous cropping soil.
【Objective】In recent years, with the promotion of rain-shelter cultivation and double cropping techniques, grape production in hot zones has achieved off-season and high-efficiency production. However, hot-region grapes face problems such as poor flower bud differentiation, uneven germination, and "flower running", which are the main constraints on stable and high-quality production. This study aims to systematically investigate and evaluate the inflorescence attachment characteristics and development quality of 98 grape germplasms in hot zones Guangxi, clarify the adaptability differences among different germplasms in hot zones, and provide theoretical basis and technical guidance for variety breeding and production management.【Method】This study investigated and evaluated the germination rate, flower bud rate, shoot formation rate, number of inflorescences per shoot, inflorescence attachment node, inflorescence type and quality of 98 grape germplasms in hot zones Guangxi for two consecutive years, covering European, American, and European-American hybrids. It deeply analyzed the quality differences and patterns among different varieties and inflorescence attachment nodes.【Result】Under the treatment of hydrogen cyanamide, all 98 germplasms could germinate and form shoots smoothly, among which 92 varieties could form normal inflorescences. The average germination rate was 90.42%, the shoot formation rate was 92.13%, the flower bud rate was about 61.06%, and the average number of inflorescences per shoot was 1.67. However, abnormal inflorescences were quite prominent, with a total proportion of 40.56%. This study classified abnormal inflorescences into three major types: tendrils type, differentiation cessation type and trophic tissue type. Among them, the tendril type was the most common, further divided into one to five tendril types, and all investigated varieties had two tendrils type inflorescences; the differentiation cessation type included single head type (only scales or death point), tendrils death point type, and branch death point type; the trophic tissue type included branch tendril and leaf tendril types. Shine Muscat showed all abnormal types and were representative materials of high sensitivity. Among the 8 investigated nodes, the inflorescence attachment was most concentrated at the 3rd and 4th nodes, accounting for 27.99% and 27.06% of the total inflorescences, respectively. The abnormal inflorescence rate at the 3rd node was the lowest, only 17.22%. Further population analysis indicated that V. vinifera L.×V. labrusca L. had higher flower bud rates (68.60%), more inflorescences per shoot (about 1.8), and higher normal inflorescence rates than V. vinifera (flower bud rate 46.59%). Moreover, varieties with high germination rates, flower bud rates, and shoot formation rates had more inflorescences per shoot and significantly lower abnormal inflorescence rates.【Conclusion】The attachment node of inflorescences significantly affects their quality performance. Among them, the middle nodes, especially the 3rd node, had the lowest abnormal inflorescence rate. Therefore, in production, for varieties prone to abnormal inflorescences, it is recommended to prioritize the retention of inflorescences at the 3rd node. Varieties with high germination rates, flower bud rates, and shoot formation rates and more inflorescences per shoot are more likely to obtain normal and high-quality inflorescences. Different grape populations show significant differences in inflorescence development and abnormal occurrence. V. vinifera L.×V. labrusca L. perform better in hot zones, with higher flower bud rates and normal inflorescence proportions. They are recommended as the preferred germplasm resources for cultivation in hot zones.
【Objective】Jasmine (Jasminum sambac) exhibits significant sexual reproductive barriers, severely impeding germplasm innovation. Fasciclin-like arabinogalactan proteins (FLAs) play crucial roles in plant reproduction development. This study conducted a genome-wide identification and analysis of the FLA gene family in jasmine, then investigated their fundamental characteristics and expression patterns, thereby providing a theoretical foundation for understanding the biological functions of the JsFLAs in reproduction development.【Method】The HMMER 3.0 software was used to screen and identify members of the FLA gene family in the jasmine genome, with further validation through Smart and CD-Search. Websites such as ExPASy, SignalP 5.0, big-PI Plant Predictor, NetNGlyc-1.0, and Plant-mPLoc were used to analyze the physicochemical properties and subcellular location of JsFLAs. MEGA, TBtools, MEME, and PlantCARE were utilized for phylogenetic tree construction, chromosome location, gene structure analysis, protein conserved motif identification, and promoter cis-element prediction. Transcriptional data were analyzed to determine the expression characteristics of JsFLAs in stigmas at various time points after pollination and in flowers at different developmental stages. Quantitative real-time PCR (qRT-PCR) was used to detect the expression pattern of JsFLA2 in jasmine, and its subcellular location was analyzed through transient transformation of tobacco leaves. Finally, the biological function of JsFLA2 was verified through heterologous expression in Arabidopsis thaliana.【Result】A total of 24 JsFLAs were identified in the jasmine genome, named JsFLA1-JsFLA24. These proteins consisted of 159-515 amino acid residues, with molecular weight of 17.02-56.34 kDa and isoelectric point of 4.20-9.69. All members contained 1-2 fasciclin-like domain (FAS), 1-2 AGP glycosylation sites, and a glycosylphosphatidylinositol (GPI) anchored site, and 19 members contained signal peptide (SP). Except for JsFLA5 which was localized in the nucleus, all other members were located on the plasma membrane. The JsFLAs were divided into four subclasses, with conserved motifs within each group. The JsFLAs were unevenly distributed across 11 chromosomes. The JsFLAs contained 0-3 introns and 1-3 exons. 21 JsFLAs were expressed in stigmas at various time points after pollination, and 20 were expressed in flowers at different developmental stages. The JsFLAs promoters included elements responsive to growth and development, plant hormones, and abiotic stress. Further research revealed that the significantly differentially expressed JsFLA2 encodes 405 amino acids, is most similar to OeFLA1, exhibits the highest expression in flowers, and is localized on the plasma membrane. Heterologous expression of JsFLA2 in A. thaliana showed that the transgenic lines exhibited severe fertility defects, including reduced pollen viability, decreased seed number, and shorter siliques.【Conclusion】This study identified 24 FLA gene family members in jasmine. Functional validation confirmed that JsFLA2 is closely related to pollen fertility in jasmine.
