【Objective】 The AP2/ERF (APETALA2/ethylene responsive factor) superfamily is a group of transcription factors that play important regulatory roles in plant growth and development, as well as in response to adverse environmental stressors. The AP2/ERF transcription factors are widely present and have many members in plants. Exploring the function of AP2/ERF family gene on grain size provides important genetic resources for regulating grain shape in rice. 【Method】OsDREB1J gene (LOC_Os08g43200) was cloned by homologous recombination, and its basic characteristics, tissue expression characteristics, and the relative expression patterns under plant hormones were analyzed by bioinformatics and qRT-PCR. The transactivation activity and subcellular localization of OsDREB1J were analyzed by yeast heterologous expression, transient expression of rice protoplasts and tobacco. The overexpression and knockout mutant transgenic rice plants of OsDREB1J were obtained by genetic transformation system, and the grain size phenotypes were analyzed by phenotypic analysis technology. 【Result】Subcellular localization analysis showed that OsDREB1J was localized in the nucleus. Bioinformatics showed that the full-length coding sequence of OsDREB1J was 711 bp, encoding 236 amino acids. OsDREB1J protein had no transmembrane structure, and the molecular weight of 27.47 kDa, the theoretical isoelectric point of 5.54, and had a conserved AP2 domain unique to the AP2/ERF family. The cis-acting elements analysis of OsDREB1J promoter showed that the promoter contained cis-acting elements related to hormone response, light and stresses response. The qRT-PCR analysis showed that OsDREB1J was expressed in different tissues of rice with no tissue specificity, and the relative expression level in panicle was the highest. At the same time, OsDREB1J was induced or reduced by different hormone. Transcriptional activation analysis showed that the full-length of OsDREB1J has no transcriptional activity, but the C-terminal fragment was sufficient for the transactivation ability. Phenotypic analysis showed that the grain length, length-width ratio and thousand grain weight of osdreb1j mutant were significantly higher than those of ZH11, OsDREB1J overexpression transgenic rice plants displayed opposite phenotypes, while changing the expression of OsDREB1J did not affect rice grain width. These results show that OsDREB1J may affect grain size by regulating cell length rather than cell proliferation and cell expansion. 【Conclusion】In conclusion, OsDREB1J may be involved in regulating rice grain size through hormone signaling pathway.

【Objective】 Optimal reduction of nitrogen (N) fertilizer application is a sustainable management strategy in rice production. The effects of lowering N fertilizer input on grain yield and rice quality of early and late-season dual-use rice in South China were investigated, which could provide a theoretical basis for high-quality and high-yield cultivation and nitrogen management of the ‘Simiao Rice’. 【Method】 A two-year in-situ field trial was carried out at the Dafeng Experimental Base of the Guangdong Academy of Agricultural Sciences from 2022 to 2023, two early and late-season dual-use ‘Simiao Rice’ (19Xiang and Nanjingxiangzhan) were used as test cultivars, and a two-factor split-plot experimental design was adopted. The main plots were a 20% reduced N fertilizer application rate treatment (RN) and the conventional N fertilizer application rate treatment (CN). The split plots were rice varieties, to analyze the changing characteristics of early and late-season dual-use rice yield and quality under RN conditions. 【Result】Compared with CN, RN did not change the grain yield in the late season, but significantly decreased the grain yield in the early season by an average of 11.7% in the two years. The decrease in grain yield under RN conditions was related to the decline in total spikelet. In the early season, RN did not affect milled rice rate, chalky grain rate, and chalkiness, but significantly reduced head rice rate by an average of 3.30% in the two years. RN had no effect on the hardness of cooked rice in the early season, but significantly reduced its protein content, stickiness and taste value of cooked rice, with an average reduction of 0.61%, 12.80% and 2.80%, respectively, and significantly increased its amylose content by an average of 1.23%. RN did not influence the milled rice rate, head rice rate, chalky grain rate, chalkiness, amylose and protein content, and the hardness, stickiness, and taste value of cooked rice in the late season. In addition, the relevant analysis showed that the decrease in head rice rate of RN treatment in the early season might be related to the decrease in protein content, while the decrease in stickiness and taste value was related to the increase in amylose content. 【Conclusion】RN decreased the grain yield, milling quality, and eating quality in the early season, while did not alter the appearance quality in the early season, the grain yield, milling quality, appearance quality, and eating quality in the late season. Therefore, in the production of early and late-season dual-use rice, it was necessary to ensure an adequate N supply in the early season to maintain grain yield and rice quality, while reducing N fertilizer by 20% in the late season could still achieve stable and high-quality rice production under current N fertilizer application levels. Keywords:

To improve the quality of artificially cultivated licorice, a pot experiment was conducted at Yulin University using Ural licorice as the experimental material to analyze and evaluate its biomass, physiological and biochemical indicators, and root anatomical structure after adding exogenous silicon under drought stress. The results showed that the addition of exogenous silicon significantly increased the accumulation of dry matter in licorice under drought stress; the synthesis of glycyrrhetinic acid and glycyrrhizinwas significantly promoted; under drought stress, exogenous silicon addition increased root dry weight from 0.93 g/plant to 1.31 g/plant; the synthesis and accumulation of glycyrrhizin and glycyrrhetinic acidwere promoted, malondialdehyde contentwas reduced, leaf proline content and root soluble sugar contentwere increased, and xylem area/cross-sectional area and phloem/anatomical cross-sectional areawere increased; The addition of exogenous silicon significantly increased the hydraulic conductivity of licorice plants by 39.15% and 302% under two different soil moisture conditions, and the hydraulic conductivity and root injury volume of licorice plants were significantly positively correlated with licorice yield. The addition of exogenous silicon under drought stress improved the quality of licorice, promoted the synthesis and accumulation of secondary metabolites, enhanced root water absorption efficiency and overall hydraulic conductivity, and participated in the formation of root tissues under stress, thereby increasing licorice yield.

To investigate the synergistic effect of side deep nitrogen reduction fertilization and silicon plus zinc fertilizer on the yield and the lodging resistance of rice, traditional fertilization and side deep nitrogen reduction fertilization were carried out using ‘South japonica 9108’ as material, with four treatments including silicon fertilizer, zinc fertilizer, silicon plus zinc fertilizer and no fertilizer, respectively. The number of stems and tillers, the physical characteristics of culm, the lodging resistance, the yield were studied under different treatments. The results showed that: (1) compared with traditional fertilization, side deep nitrogen reduction fertilization could increase the number of stems and tillers, the number of effective panicle, the yield, the stem width, and enhance the lodging resistance significantly. (2) Applying side deep nitrogen reduction fertilization with silicon fertilizer could reduce the basal inter node length, enhance the bending resistance and reduce the lodging coefficient; applying side deep nitrogen reduction fertilization with silicon plus zinc fertilizer had the best tillering ability, the most big number of effective panicle, the strongest culm and the highest yield. (3) Under fertilization methods, applying silicon plus zinc fertilizer could promote the growth of rice effectively, and reach the biggest number of effective panicle, but the effect of other traits on rice was more complicated, the superposition effect could not be achieved.

The aims were to study the growth and development law of Yutai rice under different accumulated temperature conditions, and to explore the influence of sunshine hours and temperature in different growth stages on the yield factors of Yutai rice, and to provide agricultural meteorological service basis for optimal planting of rice in Yutai area. A Logistic growth model was constructed based on the growth index data of Yutai rice from 2017 to 2022 and meteorological factors such as accumulated temperature during growth period. By using statistical methods such as correlation analysis and regression analysis, the influence of light and temperature in different growth stages on rice yield factors was analyzed, and the prediction model of yield factors was established accordingly. The results showed that the overall accuracy of Logistic model was high in the simulation of rice growth and development in Yutai, and the Root Mean Square Error (RMSE) between the simulated value and the measured value was between 0.591 and 5.100, the Normalized Root Mean Squared Error (nRMSE) was between 0.087 and 0.107, and the R² between the simulated value and the measured value was between 0.970 and 0.996. The number of sunshine hours in tillering, jointing, booting and grain filling maturity of rice was significantly correlated with yield, and the accumulated temperature in heading and grain filling maturity was significantly correlated with yield. The prediction model of rice yield and grain number per ear was established by multiple linear regression method, which was verified by historical band and histogram. The prediction model has high accuracy.

Xanthomonas oryzae pv. oryzae (Xoo) causes bacterial blight in rice, which reduces crop yield and leads to significant economic losses.  Bacterial sigma (σ) factors are highly specialized proteins that allow RNA polymerase to recognize and bind to specific promoters.  σ⁷⁰ factors also regulate the expression of genes involved in stress response and virulence.  However, the role of RpoD in Xoo is still unclear.  In this study, we found that σ⁷⁰ factor RpoD is quite conservative among phytopathogenic bacteria, especially in Xanthomonas sp.  In Xoo, PXO_RpoD plays an important role in oxidative stress tolerance and cell motility, as well as being essential for full virulence.  Cleavage under targets and tagmentation (CUT&Tag) analyses indicated that RpoD mediates the type three secretion system (T3SS) by regulating the regulation of hrpG and hrpX.  By performing bacterial one-hybrid and electrophoretic mobility assay (EMSA), we observed that RpoD directly bound to the promoters of hrpG and hrpX.  Collectively, these results demonstrate the transcriptional mechanism and pathogenic functions of RpoD in regulating cell motility and oxidative stress response, providing novel insights into potential targets for disease control.

The practice of conservation tillage or straw return to the farmland influences the grain yield and quality of rice (Oryza sativa).  The key volatile compound responsible for the fragrance of fragrant rice is 2-acetyl-1-pyrroline (2-AP), which is significantly affected by field management measures.  The purpose of this study was to investigate the impact of tillage management and straw return on the grain yield and biosynthesis of 2-AP in fragrant rice.  This study was conducted over two years in 2016 and 2017 and used two fragrant rice cultivars (Meixiangzhan 2 and Xiangyaxiangzhan) as materials.  The experimental design consisted of different tillage management and straw return treatments, which included three tillage management regimes: rotary tillage (T0), minimum tillage (T1), and no tillage (T2); and two straw return treatments: without straw return (S0) and straw return (S1).  The straw used for the experiment was sourced from the residue of the corresponding fragrant rice cultivar harvested in the early season.  Tillage management and straw return substantially affected the grain yields, grain quality, and 2-AP contents of both fragrant rice cultivars.  Compared with the T0S0 treatment, tillage management and straw return resulted in 2-AP content improvements in 2016 (12.41–116.85%) and 2017 (34.85–103.89%) on average.  Higher 2-AP contents were also detected in both fragrant rice cultivars in the T2S1 and T1S1 treatments.  A structural equation model (SEM) demonstrated that the activities of enzymes related to fragrance metabolism in the leaves and grain jointly regulated the biosynthesis of precursors of fragrance metabolism in the grain, which further promoted the accumulation of 2-AP.  In addition, a principal component analysis indicated that the T1S1 treatment was positively correlated with both 2-AP and grain yield.  The SEM demonstrated that the enzymes related to nitrogen metabolism, parameters related to photosynthesis, and yield components contributed to the grain yield.  The T1S1 treatment resulted in the highest average grain yield of 760.75 g m^–2, which could be attributed to increases in various attributes, such as the leaf area index, SPAD value, nitrogen metabolism, panicle number m^–2, and grain number per panicle.  In summary, the minimum tillage and straw return (T1S1) treatment is more effective at simultaneously improving both the grain yield and 2-AP content in fragrant rice.

To screen suitable rice varieties for planting in the Luoshan County of southern Henan rice region, a regional experiment was conducted on 8 hybrid indica rice varieties, including Liangyou 2189 and Ganliangyoujiusimiao, Fengliangyou 4 was used as a control(CK), to identify their characteristics such as growth period, agronomic traits, and yield. The results showed that the entire growth period of the tested varieties was 132-138 days, and the difference was not significant. In terms of agronomic traits, the plant height ranges from 127.0 to 148.0 cm, with Nuoyou 962 being the highest and other varieties around 130 cm; the setting rate was 76.3%-90.2%; the thousand grain weight ranges from 22.9 to 28.8 g. In terms of yield, the Ganliangyoujiusimiao, Chun 9 liangyouyazhan, and Liangyou 2189 had higher yields, with yields of 9 362.82, 8 958.02, and 8 868.07 kg/hm², respectively, which were 4.2% to 10.0% higher than the CK. Overall, Ganliangyoujiusimiao, Chun 9 liangyouyazhan, and Liangyou 2189 have lush growth, good plant and leaf types, and good yield performance.

The high yield cultivation techniques of Yuxiangliangyouxiangsi based on its demonstration planting performance in Jianghua Yao Autonomous County, Hunan Province were summarized. This variety has a moderate growth period, strong disease resistance, multiple effective panicles, high yield, and excellent rice quality, making it suitable for promotion and planting as double season late rice in study area. Its high yield cultivation techniques include selecting fertile and easily irrigated fields as seedling fields, soaking seeds in a timely manner to promote germination, and cultivating strong seedlings; transplanting at appropriate times and plant densely at 15-18 days of seedling age; heavy application of base fertilizer, early application of tillering fertilizer, and skillful application of ear grain fertilizer; shallow water seedling establishment, thin water tillering, alternating dry and wet irrigation after seedling establishment, and cutting off water supply 5-7 days before harvesting; appropriate timing and medication for weed control, combined with the occurrence of pests, diseases, and rodents in the field, selecting suitable pesticides for green prevention and control; when the rice is 95% ripe, harvest it mechanically on sunny days and promptly sun dry or dry it before returning it to the warehouse. This article provides a reference for promoting the cultivation of Yuxiangliangyouxiangsi in Jianghua and related areas.

The breeding process of Qiaoliangyoujingxiangsizhan was introduced, the main characteristics and cultivation techniques of this variety were summarized and analyzed. Qiaoliangyoujingxiangsizhan is an indica two-line hybrid rice variety developed through systematic breeding, with Xi 08S as the female parent and Jingxiangsizhan as the male parent. High yield, excellent quality, and moderate resistance to rice blast disease were demonstrated in regional and production trials. Its high yield cultivation techniques include timely sowing, pesticide soaking, and moderate sowing; suitable transplanting time; apply sufficient base fertilizer, apply early and heavy tillering fertilizer, and increase the application of phosphorus and potassium fertilizers; select suitable pesticides for chemical weed control 5-7 days after rice transplantation; appropriate timing and application of pesticides to prevent and control diseases and pests such as rice false smut and rice thrips. This article provides a reference for the cultivation of this variety as mid season rice in the middle and lower reaches of the Yangtze River and related areas.

By studying the effects of different sowing dates on the growth characteristics and tillering dynamics of rice seedlings during the vegetative growth stage, this paper provides a basis for scientifically selecting the sowing and transplanting dates for rice production and promoting stable and high yields. Taking the main cultivar ‘Longjing 31’ in the Sanjiang Plain as the test material, four sowing periods were set with a time step of 10 d between adjacent sowing periods, the local multi-year average sowing period was set as the second period (T₂), and one forward phase (T₁) and two backward phases (T₃-T₄) were set together to carry out the trial. The results showed that as the sowing date delayed, the rice development period was delayed and shortened, the development process of rice accelerated, the number of unsuitable days of daily temperature suitability decreased, the temperature suitability during the development period increased, and the effective accumulated temperature of ≥ 10℃ decreased. The coefficient of determination of effective accumulated temperature (≥10℃ ) and tiller number was above 92.8 %, and the influence coefficient of effective accumulated temperature (≥10℃ ) on tiller number was between 4.7 and 8.9; T₁ sowing stage encountered a stage low temperature with the lowest temperature of 3.3 °C from regreening to tillering stage, and the daily temperature suitability for 7 consecutive days was less than 0.3, of which 4 days was 0, and the seedling trait index was the lowest; the maximum plant height and leaf area per plant were 73 cm and 103.27 cm² at T₂ sowing stage, the dry matter of each plant was 1.01 g, the maximum number of tillers in the hole reached 18 plants. Above all, the seedling quality index was the highest in T₂, followed by T₃, and May 11-21 was the best transplanting period. The research results can provide theoretical basis for the scientific selection of transplanting period, seeking benefits and avoiding harm, and promoting stable and high yield in rice planting.

To explore the application potential of biochar based fertilizer to increase the yield and income of rice production in middle-low yield field, field plot experiments were conducted in Yangxin and Shashi area of Hubei Province. The effects of no fertilization (CK), customary fertilization (F), customary fertilization + biochar (FB), biochar based fertilizer (BF1), biochar based fertilizer reduction of 10% (BF2) and biochar based fertilizer reduction of 20% (BF3) on rice yield, nutrient uptake and cost-benefit were studied. The results showed that the application of biochar based fertilizer increased rice yield and straw biomass, and BF1 treatment significantly increased rice yield compared with F treatment, which increased by 11.09% and 9.51% in middle and low yield fields, respectively. Biochar based fertilizer treatment promoted the nutrient uptake of rice, the above-ground N and P accumulations of rice treated with BF1 and BF2 were higher than those treated with F. At the same time, compared with F treatment, BF1 and BF2 treatment significantly improve the apparent recovery rates of N, P and K in middle yield field and the apparent recovery rates of P and K in low yield field. And, BF2 treatment had the highest apparent recovery rate of N (38.99%) in middle yield field, which was 29.41% higher than that of F treatment. In addition, BF1 and BF2 treatments increased the income of rice planting in middle-low yield fields, among which BF1 treatment had the highest income, with an increase of 560.7 yuan/hm² and 1460.3 yuan/hm² compared with F treatment in low and middle yield fields, respectively. In conclusion, the application of 0%-10% reduction of biochar based fertilizer can improve rice yield and fertilizer use efficiency, and increase farmers’ planting income, which is suitable for rice production in middle-low yield field.

This study aims to evaluate the salt tolerance of Guangdong Simiao rice varieties during the germination and seedling stages, providing a scientific basis for variety selection and theoretical guidance for Simiao rice production. Fifteen Guangdong Simiao rice varieties were selected as research objects, and their performance at different growth stages was observed through salt stress treatment, with specific evaluation indicators including germination rate and seedling survival rate. The research results show that salt stress significantly inhibits the seed germination rate and germination potential of Simiao rice varieties. Notably, during the germination and seedling stages, hybrid rice shows stronger tolerance compared to conventional rice, especially 'Qingxiangyou 19 xiang' and 'Ruanhuayoujinsi', which exhibit higher salt tolerance. In the seedling stage, varieties such as 'Xiangxiuzhan', 'Lixiangzhan', 'Nanjingxiangzhan', 'Hengfengyouyouxiang', and 'Gengxiangyoulisimiao' also show higher salt tolerance. Given the significant differences in salt tolerance among different varieties, it is recommended to give priority to varieties or hybrids with stronger salt tolerance after comprehensively considering other variety demand factors. In addition, different measures should be adopted for different varieties when facing salt stress to improve yield stability.

【Objective】Cadmium (Cd) is the predominant pollutant in China’s arable land, with rice cultivated on these contaminated soils being a significant dietary source of Cd for the population. This study aims to tissue-specifically express OsNRAMP5, a transporter responsible for the majority of Cd uptake in rice, to investigate strategies for developing low-Cd rice varieties and provide a reference for molecular design breeding to cope with Cd pollution. 【Method】To drive the expression of OsNRAMP5 in rice, we utilized a 2 500 bp sequence upstream of the OsLCT1 start codon as the promoter. The red fluorescent protein mRFP was fused to the C-terminus of OsNRAMP5 to visualize its tissue localization. After obtaining independent homozygous transgenic lines, the transcripts of the OsNRAMP5 were first detected using qRT-PCR, and its tissue localization in roots and nodes was observed via laser confocal microscopy. Subsequently, the accumulation and tolerance of Cd were evaluated in transgenic and wild-type rice under varying concentrations of Cd treatment. Furthermore, plants were grown in Cd-contaminated paddy soil, and the accumulation of Cd and other mineral elements in seeds and leaves, as well as related yield traits, were measured. 【Result】Under the drive of the OsLCT1 promoter, OsNRAMP5 was expressed mainly in the epidermis, exodermis and stele of roots, as well as in the phloem area of enlarged vascular bundles and diffuse vascular bundles in nodes, differing significantly from the native expression pattern of OsNRAMP5 in rice. Compared to wild-type rice, the transgenic lines exhibited increased Cd accumulation in roots, decreased Cd accumulation in shoots, and enhanced tolerance to Cd stress during the seedling stage. When cultivated in Cd-contaminated paddy soils, plant height and grain yield were unaffected by the ectopic expression of OsNRAMP5, while Cd accumulation in seeds and leaves significantly decreased in the transgenic lines. The Cd content in seeds decreased by over 80%, with a greater reduction ratio compared to that in leaves. Although the Mn content in seeds and leaves slightly decreased, the expression of OsNRAMP5 had little impact on the accumulation of other mineral elements such as Fe, Zn, and Cu. 【Conclusion】The expression of OsNRAMP5 driven by the OsLCT1 promoter greatly decreases the Cd migration toward rice seeds by reducing Cd transport to the aboveground parts from roots and increasing the Cd transporting to leaves at nodes. Therefore, the expression of OsNRAMP5 under the control of the OsLCT1 promoter is an effective strategy to reduce Cd accumulation in rice seeds.

The pathogen and symptoms of rice spike rot disease were introduced. The occurrence regularity of rice spike rot disease was expounded from the occurrence conditions and epidemic regularity of the disease. The agricultural control measures of rice spike rot disease were introduced from the aspects of cultivation management, fungus source accumulation and selection of resistant varieties. The control effects of different pesticides on rice spike rot disease were also introduced. It is suggested that the control of rice spike rot disease should be based on agricultural control measures, including scientific cultivation, timely elimination of fungal sources and selection of disease-resistant varieties, and the chemical control should be included at the opportune moment. The occurrence and damage of spike rot disease were expected to be effectively controlled to a certain extent while ensuring the safety of grain production.

To screen high quality and high yield rice varieties suitable for production in Jiangmen, Guangdong, a variety screening experiment was conducted on 7 rice varieties, namely Meixiangzhan No.2 (CK), Zhongxiang No.5, Jiangnongxiangzhan No.1, Huahang No.82, Yueyasimiao, Huahangyuzhan, and Yuehesimiao, to analyze their agronomic traits and yield performance in the study area. The results showed that the average growth period of each tested variety was between 124 and 127 days; mild occurrence of sheath blight in various varieties, including Zhongxiang No.5, Jiangnongxiangzhan No.1, and Huahangyuzhan with mild occurrence of white leaf blight, while other diseases did not occur; the rate of panicle formation was stronger in the Yuehesimiao. In terms of yield, the average yield of various varieties ranges from 5 382.5 to 6 750.0 kg/hm², with the highest yield of Yueyasimiao, which increased by 25.4% compared to CK. Overall, the growth period, yield, and resistance of Yueyasimiao, Huahangyuzhan, Yuehesimiao, Huahang No.82, and Jiangnongxiangzhan No.1 were all relatively ideal and suitable for promotion and planting in Jiangmen and related areas.

The production practice was combined of high quality rice in the Lixiahe area of Yancheng, Jiangsu, and the cultivation techniques of high quality rice production from the aspects of planting method selection and variety selection were summarized and analyzed. The planting method should choose light and simplified machine insertion; select high quality rice varieties with high yield, high rice yield, good resistance, wide adaptability, and high stability; to achieve precise bed preparation, seed control, water control, and chemical control, in order to cultivate seedlings that meet high yield requirements and mechanical operation requirements; straw returning to the field and leveling, planting with reduced plant size and increased density, and multiple holes and fewer roots at a seedling age of 3.5 to 3.8 leaves; balance the ratio of organic and inorganic fertilizers, as well as the ratio of nitrogen, phosphorus, potassium, and silicon fertilizers, and apply fertilizers appropriately and timely; adopt alternating wet dry irrigation based on the growth of seedlings; coordinate agricultural control, biological control, physical control, and chemical control measures to timely prevent and control pests and diseases; pay attention to preventing cold damage and lodging during the growth process; harvesting rice at 95% maturity, followed by processing such as low temperature drying and low temperature refrigeration. Relevant cultivation techniques provide references for the production of high quality rice.

To explore the effect of graphene oxide (GO) treatment on rice seed germination under salt stress, this experiment used the rice variety 'Harbin Japonica Rice 15' as the experimental material. Under normal conditions and salt stress (0.05 mol/L NaCl), GO was induced at different mass concentrations (0, 25, 50, 100 mg/L) to detect the changes in antioxidant enzyme activity, malondialdehyde, and osmotic regulator content of rice seeds after different treatments. The results show that: (1) low concentrations of GO (25 mg/L) can promote the germination of rice seeds, while high concentrations of GO (50, 100 mg/L) significantly inhibit their germination. 25 mg/L GO can increase seed vitality and improve germination rate under salt stress; (2) high concentrations of GO and NaCl combined treatment can further exacerbate the inhibitory effect of salt stress on rice seed growth, increase antioxidant enzyme activity, reduce malondialdehyde content, and alleviate oxidative stress response; (3) GO treatment promotes the synthesis and accumulation of osmotic regulators, increases the osmotic regulation ability and salt resistance of rice seeds, strengthens the salt tolerance of seedlings, and significantly improves their emergence and seedling efficiency in salt environments. Low concentration GO can promote rice germination, while high concentration GO has certain harm to rice growth. Especially under salt stress, high concentrations of GO can increase the toxicity of salt stress on rice growth. It is suggested that high concentration GO related fertilizers should be used with caution in rice production practice in saline alkali areas.

To select the most effective microbial product for in-situ decomposition of rice straw under cool conditions in Northeast China, and to determine the optimal dosage of microbial product coupling urea, this study conducted comparative experiments, and used the decomposition rate of rice straw, biological characteristics and yield of rice as indicators to define the optimal microbial product and the dosage of urea. The results showed that the independently developed microbial product NKY showed better field application effects. The straw decomposition rates of Hongqi Farm and Wanchang Town were 68.8% and 67.2%, respectively, which were 38.5% and 35.5% higher than CK. The height, tiller number, and dry weight of rice were also increased, and the rice yield increased by 6.0% and 6.8%, respectively. The optimal dosage for coupling urea with microbial product NKY was 75 kg/hm². Compared with no urea application, the straw decomposition rate increased by 8.7%, and the yield increased by 6.2%. In summary, the microbial product NKY not only has good degradation ability of rice straw, but also could promote crop growth and improve crop yield, which has a better application prospect.

A field experiment was carried out from June to November 2021 in tidal flat of Nantong, Jiangsu Province to study the effects of different exogenous silicon fertilizers spraying on rice yield, dry matter and nutrient accumulation and transport in various organs and rice quality, with ‘Nanjing 5055’ as the test variety. Five treatments were set up in the experiment, including spraying water treatment (CK), sugar alcohol silicon treatment (SF₁), seaweed liquid silicon treatment (SF₂), liquid silica-zinc fertilizer treatment (SF₃) and highly active ionic liquid silicon treatment (SF₄). The results showed that (1) compared with CK, rice yield under SF₁, SF₂, SF₃ and SF₄ increased by 9.24%, 7.31%, 0.28% and 3.64%, respectively, and reached a significant level under SF₁. At the same time, the number of grains per panicle, the number of solid grains, the weight of thousand grains, the length of panicle and the density of grains were increased significantly under SF₁ (P<0.05). (2) The above ground dry matter accumulation of rice at maturity was SF₁>SF₂>SF₄>SF₃>CK. At heading stage, nitrogen accumulation in the above-ground part and potassium accumulation in the upper part of the ground under SF₁ and SF₃ were significantly increased under each spraying treatment. Nitrogen accumulation in the lower panicle and above-ground parts of SF₁, SF₃ and SF₄ at maturity was significantly increased (P<0.05). The distribution of nitrogen and potassium accumulation in each organ of rice at heading stage was in the order of stem sheath>leaf>ear. The distribution of nitrogen accumulation at maturity was in the order of spike>sheath>leaf, and the distribution of potassium accumulation was in the order of sheath>ear>leaf. (3) Compared with CK, leaf dry matter transfer (SF₃) and ear dry matter increase (SF₁, SF₂ and SF₃) were significantly increased. Nitrogen transfer in stem sheath (SF₂, SF₃ and SF₄) and leaves (SF₁) and nitrogen increase in panicle (SF₁, SF₃ and SF₄) were significantly increased. The transfer volume of potassium in stem sheath (SF₃) and leaf (SF₁) and the increase of potassium in panicle (SF₃) were significantly increased (P<0.05). (4) Rice yield was positively correlated with spike dry matter increase and nitrogen transfer, significantly positively correlated with dry matter accumulation and spike nitrogen accumulation at maturity, and significantly negatively correlated with leaf potassium accumulation. (5) Different exogenous silicon fertilizers spraying had no significant effects on the appearance and processing quality of shoal rice under the experimental conditions. Therefore, spraying appropriate exogenous silicon fertilizer (especially sugar alcohol silicon) on the leaf surface could significantly increase rice yield in this coastal mudflat area. Spraying exogenous silicon fertilizer mainly improves the number of grains per spike and the quality of 1000 grains, increasing the accumulation of dry matter and nitrogen in the rice spike.

To solve the practical problems in the existing “non-grain” cultivated land improvement technology, such as high cost and poor regional suitability, a field experiment was carried out in the typical “non-grain” reclaimed rice field in the hilly area of eastern Zhejiang Province. The effects of different organic amendments and combinations (T₁: biochar based fertilizer, T₂: potassium fulvic acid, T₃: organic fertilizer + biochar based fertilizer, T₄: organic fertilizer + potassium fulvic acid), and tillage depth (D: deep tillage with 20 cm, S: shallow tillage with 15 cm) on topsoil properties, rice yield and economic benefits were analyzed. The results showed that the application of different organic amendments could significantly increase the yield of rice, among which T₄ and T₃ had the best effects, especially under the condition of deep ploughing. Compared with the conventional control (S-CK), they could increase the yield by 3.7 t/hm² (48.8%) and 3.4 t/hm² (44.5%) respectively, and the economic benefit reached 2391-3101 yuan/hm² in the current season. Deep ploughing decreased soil pH by 0.2 units on average, but significantly increased soil organic matter (SOM), total nitrogen (TN), alkali-hydro nitrogen (AN), available phosphorus (AP) and cation exchange capacity (CEC). Among them, the SOM in D-T₄ and D-T₃ increased by 11.5% and 11.3%, respectively, compared with S-CK. The correlation analysis showed that rice yield was significantly positively correlated with agronomic characters (effective panicle, panicle length, spikelet per panicle and seed setting rate) and soil fertility indexes (SOM, TN, AN, AP, AK and CEC) (P<0.01). Therefore, the organic amendments combinations of organic fertilizer and biochar based fertilizer or potassium fulvic acid, with moderate mechanical deep ploughing, can simultaneously achieve tillage layer reconstruction and directional fertilizer cultivation, and promote soil improvement efficiency in reclamation area. This technology has great potential to be popularized in the “non-grain” reclaimed rice field in hilly areas.

Soil water-soluble organic carbon (WSOC) changed with cultivation methods is of great significance to crop growth and soil carbon cycle. In this study, a field experiment was conducted to compare the effects of rotary tillage (RT) and no tillage (NT) on the content and spectral characteristics of WSOC during the key growth period of rice in rice-wheat rotation system in the Taihu Lake Region. The results showed that the content of soil organic carbon (SOC) in RT and NT treatments increased from 21.73 g/kg and 21.30 g/kg before rice planting to 21.95 g/kg and 23.49 g/kg after rice harvest, respectively. Meanwhile, the content of water-soluble organic carbon in RT and NT treatments increased from 1.74 g/kg and 1.66 g/kg before rice planting to 3.74 g/kg and 4.35 g/kg after rice harvest, respectively. No tillage for rice-wheat rotation system was more conducive to increasing soil carbon sequestration and water-soluble organic carbon. Under the both tillage methods, the SUVA₂₅₄ and SUVA₂₆₀ of WSOC after rice harvest decreased slightly compared to that before planting rice, and the SUVA₂₅₄ and SUVA₂₆₀ of NT were higher than those of RT, while E₂/E₃ and E₃/E₄ were both increased. No tillage was more conducive to improving the aromaticity and humification of WSOC than RT for rice-wheat rotation system. Compared to rotary tillage, no tillage was more conducive to improving the stability of WSOC and had a positive effect on increasing soil carbon sequestration in paddy soil of rice-wheat rotation system.

【Objective】 Rice blast is one of the most devastating diseases of rice production. A broad-spectrum disease resistance gene Pigm-1 was identified but its functional pathway and interactors are unknown. The screening and identification of key proteins in the Pigm-1 signaling pathway will provide an important theoretical basis for rice disease resistance breeding. 【Method】 In this study, the decoy protein pGBKT7-Pigm-1-CC^1-576 vector was constructed to detect the decoy protein self-activation, and the toxicity of the decoy protein was detected by separately transforming the plasmid pGBKT7 and pGBKT7-Pigm-1-CC^1-576 into Y2H Gold yeast. The rice disease resistance R protein Pigm-1 was screened by cDNA expression yeast library induced by rice blast fungus. The sequencing results were compared and annotated by Rice Information GateWay (RIGW). The interaction of OsbHLH148 protein was verified by Luc, Co-IP and yeast two-hybrid assays, and the tissue expression of the corresponding gene of the interaction protein OsbHLH148 was analyzed by qRT-PCR. 【Result】 The self-activation test showed that the decoy protein pGBKT7-Pigm-1-CC^1-576 did not self-activate when cotransformed with the AD plasmid, and the toxicity analysis showed that the decoy protein had little or no toxicity to yeast cells. A total of 124 proteins that may interact with Pigm-1 were obtained by screening the yeast library, and among these proteins, there are ethylene synthesis related, gibberellin synthesis related, active oxygen species clearly related, enzyme metabolism related, and some function unknown. The interaction between Pigm-1-CC^1-576 and OsbHLH148 was verified by Luc, Co-IP and yeast two-hybrid methods. Further analysis showed that OsbHLH148 can be induced by blast fungus infection, and the tissue expression analysis showed that OsbHLH148 expression level was the highest in rice leaves at 6 weeks. 【Conclusion】 In this study, 124 proteins that may interact with Pigm-1 were obtained. One of these proteins, OsbHLH148, was selected and verified to interact with Pigm-1-CC^1-576. Suggesting that OsbHLH148 may be involved in Pigm-1 mediated resistance of rice blast.

【Objective】 Rice (Oryza sativa L.) is a staple cereal crop for about half of the global population, with protein being the second-most significant nutritional component in rice grains. The storage proteins in rice grains mostly consist of glutelin, prolamin, globulin, and albumin, among which the content of easy-to-digest glutelin is the highest. Consequently, common rice increases the burden of kidney and accelerates the progression of renal disorders. The method of generating low-glutelin rice germplasm will provide novel genetic material for the cultivation of functional rice cultivars suitable for individuals with kidney diseases. 【Method】 We utilized Suxiu 867 (SX867), an elite japonica rice cultivar appropriate for cultivation in Jiangsu province, as a transgenic recipient to delete a fragment of approximately 3 500 bp between the B subfamily glutelin-coding genes GluB4 and GluB5 using CRISPR/Cas9-mediated gene editing technology. The large fragment deletion was identified by PCR using the primers corresponding to the flanking sequence of gene editing target sites, while sequence-specific primers for Cas9 and hygromycin resistance gene cassettes were used to identify the low-glutelin rice mutant absent of transgenic elements. The protein component contents of homozygous low-glutelin mutants were analyzed qualitatively and quantitatively, and the expression levels of glutelin-coding genes in rice grains were detected by quantitative PCR. The agronomic traits and quality traits of homozygous low-glutelin mutants and recipient cultivar cultivated under the same cultivation conditions were measured. 【Result】 Homozygous mutants with a 3 448 bp deletion between GluB4 and GluB5 genes were generated successfully. In the mutants, the relative proportion of glutelin decreased significantly, while that of prolamin and globulin increased significantly. The glutelin content of homozygous mutants decreased to 45.54%-49.75% compared to recipient cultivar, and the reduction level is comparable to LGC-1, a low-glutelin rice germplasm commonly used as a donor of low-glutelin trait in commercialized rice cultivars. The expression levels of B subfamily glutelin-coding genes in homozygous mutant were decreased significantly, and the changing trends was consistent with that of LGC-1 derived rice cultivar. Except that plant height decreased and grain length increased significantly, other measured agronomic and quality traits of homozygous mutants were not changed significantly compared to recipient cultivar. 【Conclusion】 Using CRISPR/Cas9-mediated gene editing technology, rice mutants with significant lower glutelin content free from transgenic elements were obtained successfully providing a convenient and quick method to generate low-glutelin germplasm.

In order to investigate the effect of irrigation of the critical growth period on rice grain yield and water use efficiency, rice cultivar 'Yuehesimiao' was conducted with five irrigation treatments, namely, irrigation during mid-tillering (IMT), irrigation during panicle initiation (IPI), irrigation during heading (IHD), and irrigation during panicle initiation and heading periods (IPI+IHD), and the whole growth period flooding irrigation (CK). The effects of irrigation at different growth periods on tiller number, plant height, photosynthesis, grain yield and water use efficiency of rice was studied. The results showed that compared with CK treatment, rice grain yield in IMT, IPI, IHD and IPI+IHD treatments decreased by 97.0%, 37.9%, 34.7% and 21.9%, respectively. Productive panicle number in IPI, IHD and IPI+IHD treatments decreased by 28.6%, 25.7% and 31.4%, respectively, but no significant difference in IMT treatment. Spikelet per panicle and panicle length in IMT and IHD treatments decreased by 49.0%, 20.0% and 13.9%, 6.4% respectively. No significant difference in plant height, spikelet per panicle and panicle length was observed in the IPI and IPI+IHD treatments relatively to control. The setting rate in the IHD and IPI+IHD treatments increased by 22.9% and 10.7%, respectively. The net photosynthetic rate in IPI, IHD and IPI+IHD treatments increased by 27.3%, 29.6% and 32.4%, stomatal conductance increased by 45.5%, 24.1% and 42.8%, and transpiration rate increased by 33.9%, 23.6% and 31.5%, respectively. Intercellular CO₂ concentration in IPI and IPI+IHD treatments increased by 0.8% and 4.1% respectively. Compared with the control, water use efficiency in IPI, IHD and IPI+IHD treatments increased by 13.6%, 19.9% and 14.6%, respectively. Irrigation during the mid-tillering period was beneficial to the increase of tiller number, irrigation during panicle initiation could increase the number of spikelets per panicle, and irrigation during heading period could increase the setting rate of rice. The panicle initiation and heading periods are critical periods for rice irrigation, which is conducive to minimizing the yield loss and improving water use efficiency. The results of the study are of great significance for water-saving, yield-enhancing and efficiency-enhancing rice cultivation in arid areas.

Winter planting green manures in southern China effectively improve soil properties and rice production through microbial community construction. However, the effects of soil communities of arbuscular mycorrhizal fungi (AMF) from different winter planting green manures on the soil properties and post-cropping rice production remain unclear. In this study, the soil AMF communities of three common winter planting patterns in Southern China, winter fallow, winter ryegrass (Lolium multiflorum L.), and winter Chinese milk vetch (Astragalus sinicus L.), were explored and their effects on post-cropping rice production were investigated. Compared with winter fallow, the winter ryegrass and winter Chinese milk vetch patterns could alleviate soil acidification, significantly increase soil AMF spore density, and improve the soil AMF community structure. Based on sterilized soil, rice production indicators such as thousand-seed weight, theoretical yield, and the grain amylose and total sugar contents of rice inoculated with AMF spores from winter Chinese milk vetch soil were 6.68-53.57% higher than those without AMF inoculation. Rice panicle weight, seed setting rate, and theoretical yield were 15.38-22.71% higher in the treatment with AMF spores from winter ryegrass soil than in the treatments with no AMF inoculation. In addition, the protein, amylose, and total sugar contents of rice grains were 14.92, 104.82, and 802.23 mg kg^-1, respectively, which were 31.31, 14.25 and 34.47% higher than those without AMF inoculation. The AMF community dominated by Glomus and Acaulospora in winter Chinese milk vetch had a more positive effect on the improvement of rice yield, while the AMF community dominated by Glomus in winter ryegrass soil was more conducive to rice quality improvement. These findings have revealed the critical role of AMF communities from green manure in rice production, which lays the theoretical basis for a promising strategy to promote the sustainable development of southern winter agriculture.

Further understanding the genetic regularity of rice harvest index in different segregating generations is beneficial to provide theoretical references for rice breeding based on the rice harvest index. In this research, isolated descendants from four distinct rice hybrid combinations were selected based on their harvest index. And then the coefficient of variation for main agronomic traits and the selection efficiency regarding the harvest index were subsequently compared and analyzed across different generations. The characteristics such as SPAD value at booting stage, plant height, and panicle length exhibited stability among different rice materials. In contrast, there was considerable variability in sword leaf length, thousand-grain weight, seed setting rate, and harvest index among hybrid rice progeny; however, these four traits remained stable in their parental lines. Notably, aboveground biological yield and panicle number per plant displayed significant variation both in hybrid parents and their offspring. The generalized heritability of the harvest index for F₃, F₃ lines and F₄ lines across all tested hybrid combinations exceeded 97%. Furthermore, selection efficiency for the harvest index in F₄ lines derived from ‘Hongxin-1S/Yuxiangyouzhan’, ‘Hongxin-1S/FL478’, and ‘Hongxin-1S/HD-YX’ surpassed that observed in their respective F₃ and F₃ lines; thus indicating a pronounced effect of single-plant selection based on harvest index within these three hybrids. Conversely, single-plant selection among offspring of ‘Hongxin-1S/Guanghong 3’ with high harvest indices did not enhance selection efficiency. It was effective to select individual plant with elevated harvest index for most of the tested rice materials from F₂ generation, which could significantly improve the selection efficiency of harvest index.

To screen rice varieties suitable for the “rice-ratooning rice-rapeseed” planting model, 13 rice varieties including Renyou 6, Zhenzaoyou 939, and Jiyou 1127, etc. were used as materials (with Lingliangyou 268 as the control), and a selection experiment of regenerated rice varieties under the “rice-ratooning rice-rapeseed” model was conducted in Changsha (research area A) and Yiyang (research area B), Hunan Province, determine indicators such as reproductive period, yield, and yield composition. The results showed that, except for Shengliangyou 358, all other varieties had suitable growth periods for planting in the study area and could safely achieve full panicle. In research area A, the annual yields of Renyou 6 and Quanzaoyou 1606 were 14.00 and 14.27 t/hm², respectively, which increased by 5.34% and 7.37% compared to the control. In research area B, the annual yields of Renyou 6, Lingliangyou 741, and Quanzaoyou 1606 were 10.58, 10.56, and 10.76 t/hm², respectively, an increase of 7.65% to 9.68% compared to the control. The above varieties all mature before mid October and can safely transition the rapeseed crop. Overall, Renyou 6 and Quanzaoyou 1606 performed well in Changsha, Hunan Province, while Renyou 6, Lingliangyou 741, and Quanzaoyou 1606 performed well in Yiyang, Hunan Province. They are suitable for planting regenerated rice varieties in the cooperative “rice-ratooning rice-rapeseed” planting model, and can be selected according to local planting conditions in each region.

The large-scale planting performance of drought resistant rice variety Hanyou 73 was combined in Donghu Production Base, Dongqiao Town, Huian County, Xiamen, Fujian Province, its “rice+vegetable” water-dry rotation cultivation techniques and its advantages in arid land were summarized and analyzed. This variety was planted in a “rice+vegetable” rotation in the research area, with a total growth period of about 128 days and resistant to bacterial leaf blight and rice blast disease, with good drought resistance; the dry grain yield of rice was 7 542.75 kg/hm². Dryland cultivation techniques include land preparation, application of base fertilizer, and rotary tillage; after seed mixing or seedling cultivation, live broadcasting or waterless machine transplanting is carried out; arrange micro sprinkler irrigation pipe belts in the field according to the walking route of the rice transplanter wheels; after emergence, water the seedlings with water for greening, tillering, and heading filling to improve seedling quality and rice seed setting rate; according to the seedling situation in the field, apply tillering fertilizer, jointing fertilizer, and heading fertilizer to cultivate strong seedlings; dryland has more grass damage than paddy fields, and generally adopts measures such as closed weeding as the main method, chemical pesticides as auxiliary, and manual removal and remediation for prevention and control; according to local pest and disease monitoring information, timely prevention and control of diseases and pests such as sheath blight and rice planthopper. The application of the “rice+vegetable” water-dry rotation model and dryland waterless machine transplanting technology has technical management advantages such as saving labor and reducing consumption, facilitating water control, and improving fertilizer utilization efficiency; and social benefits such as improving farmland utilization efficiency, conserving water resources, and improving soil environment. This article provides a reference for the promotion and application of the “rice+vegetable” water-dry rotation model in relevant region’ dry land.

The types of rice pests and diseases, as well as their occurrence rules in Huazhou City, Guangdong Province, were investigated in this study, to provide a basis for prediction, forecasting, and green control measures. Based on multi-year survey data and historical records, the species of rice pests and diseases in Huazhou from 1980 to 2023 were investigated, and the occurrence and epidemic patterns of major pests and diseases, and their causes were analyzed. It was revealed that a total of 55 types of rice pests and diseases were present in the region, comprising 21 diseases and 34 pests. Among the diseases, fungal diseases were found to be the most prevalent, with 12 types accounting for 57.1% of the total. Leaf-eating and sap-sucking pests were identified as the most common among the pests, with 12 types each, both accounting for 35.3% of the total. A preliminary exploration was conducted into the regularty of epidemic of major rice pests and diseases in the region over the years, revealing differences in the severity of pests and diseases damage across different decades. In the 1980s, severe damage was caused by pests such as Tryporyza incertulas, Nilaparvata lugens, Thrips oryzae, Orseoia oryzae and diseases such as rice blast, bacterial leaf blight, sheath blight, false smut, and rice gall dwarf disease, while other pests and diseases were relatively mild. From the 1990s onwards, an increase in severity was observed for Nilaparvata lugens, Cnaphalocrocis medinalis, sheath blight, bacterial leaf streak, and rice orange leaf disease. In the 2020s, Sesamia inferens, Chilo suppressalis, bacterial leaf streak, sheath blight, bacterial leaf blight, and southern rice black-streaked dwarf virus were found to have become more prevalent. It was concluded through a comprehensive analysis that the occurrence and evolution of these rice pests and diseases were mainly driven by a combination of three factors: the host plant (crop resistance), pathogenic organisms (or initial pest sources), and environmental conditions (including meteorological conditions, cultivation practices, and farming systems). It was also noted that different pests and diseases had their own specific factors contributing to their evolution. A reference was provided by this study for improving the management of rice pests and diseases in the region and for promoting the sustainable development of agriculture.

The lodging resistance of rice is a complex character, and the analysis of its genetic effect is valuable for improving the lodging resistance of rice. The genetic patterns and parameters of 16 lodging resistance traits in indica and japonica crossbred progeny were analyzed by using additive and dominant genetic model of plant quantitative traits. The variation of additive variance in the ratio of main effect of 9 traits ranged from 49.9% to 72.1%. The dominant variance in the ratio of dominant effect of 7 traits ranged from 48.2% to 87.1%. The additive and dominant variances of 9 traits accounted for significant or extremely significant phenotypic variances, which were controlled by both additive and dominant effects of genes. The 8 characters, such as basal folding resistance and sheath leaf thickness, were negatively correlated with lodging index, which was conducive to improving basal folding resistance and toppling resistance of rice. Indica japonica intermediate type parents have strong lodging resistance heterosis and high breeding value. Effective use of the genetic characteristics of each character has important guiding significance for breeding lodging resistant indica and japonica hybrid generation.

To understand the current status of Cd contamination and regulation in rice, this review comprehensively summarizes the following aspects: the absorption and translocation patterns of Cd in rice, Cd accumulation characteristics in different rice varieties and plant organs, the impacts of Cd on rice yield and quality, the effects on seed germination, as well as the influences on rice growth and physio-biochemical processes. Additionally, mitigation strategies for reducing Cd accumulation are systematically discussed. Based on China's current situation of rice Cd contamination, future research directions are proposed: (1) developing novel in-situ passivation materials, such as nano-adsorbent materials, which should have the characteristics of eco-friendly, cost-effective, high-efficiency, and user-friendly features; (2) creating more scientifically sound soil remediation technologies that can efficiently remove various heavy metals without damaging soil structure and ecological balance; (3) employing novel molecular breeding techniques to cultivate Cd-tolerant and stable ultra-low Cd-accumulating rice varieties, along with developing corresponding cultivation practices. This study aims to provide valuable references for Cd contamination control.

In order to explore the pollution status and health risks of heavy metals in rice grains in a county of southern Henan, 68 rice grain samples were collected in the area in September 2021. The contents of chromium, arsenic, cadmium, lead, and mercury were determined by inductively coupled plasma mass spectrometry (ICP-MS-TQ) and direct mercury detection. The risk degree of heavy metals in rice was evaluated by single factor and Nemerowcomprehensive pollution index method, and the potential health risk of heavy metals from rice grains was evaluated by target hazard quotient (THQ) promoted by US EPA. The results showed that the average content of heavy metals in 68 rice grains did not exceed the Chinese Food Hygiene Standards, but the arsenic and cadmium contents in some samples exceeded the standards. The comprehensive pollution index (P_N) of heavy metals in rice grain was 0.49, which was safe. ADD of adults and children was higher than RfD, and hazard quotients (HQ) of As were 3.11 and 4.80, which indicated that there was a certain risk of arsenic content in rice grains. The total hazard index (HI) of heavy metals to the exposed population was greater than 1, indicating that the long-term consumption of the rice by local residents may cause adverse health effects. In summary, the rice grain samples in the research area have been contaminated with arsenic, posing certain health risks. The local government needs to strengthen dynamic monitoring of the rice planting process, pay attention to the changes in the form and effective state of arsenic, ensuring food security.

The characteristics, suitable planting areas, cultivation techniques, and high-yield seed production techniques of Quanxiangyou 89 were summarized and analyzed based on its production practice. This variety is planted in the upper, middle, and lower reaches of the Yangtze River and exhibits characteristics such as suitable growth period, excellent rice quality, and high-yield; it is suitable for planting in areas with low incidence of rice blast disease, such as Pingba hilly rice growing areas in Sichuan Province and mid to low altitude indica rice growing areas in Yunnan Province. The high-yield cultivation techniques include early sowing in time and cultivating multi-tiller seedling; heavy application of bottom fertilizer, timely topdressing; dry and wet alternate pipe water and timely pest control. High-yield seed production techniques include post tobacco seed production in areas with an altitude of 250-500 meters; according to the different seed production seasons, ensure that the parental sowing difference period is between 6.5 and 7.5 leaves; soaking seeds with pesticides, spraying paclobutrazol, etc., to promote the health, dwarfism, and multiple tillering of seedlings; arranging a parent to parent ratio of 1∶8; managing fertilizer and water according to the growth of seedlings in the field; timely prevention and control of diseases and pests such as neck blight and rice planthopper based on actual field investigations and local pest and disease reports; adopting the method of young ear peeling to predict flowering period, it is advisable to use the same period as the parents in the early stage of young ear differentiation; spraying gibberellin when the panicle reaches 15%; pay attention to removing impurities and maintaining purity throughout the entire seed production process; harvesting begins when 75% of the seeds are ripe and dried promptly after harvesting. This article provides references for the demonstration and promotion of high-yield seed production techniques for Quanxiangyou 89.

Based on the rice production practice in the Southern Jiangsu Province, the high-quality and high-yield cultivation techniques of rice and their promotion strategies were summarized and analyzed. High-quality and high-yield cultivation techniques include selecting varieties with high-quality, high-yield, strong resistance, and wide adaptability according to local conditions; making preparations for seedling field configuration, nutrient soil (substrate) preparation, seed treatment, and scientific sowing; water management, fertilization management, and pest control of seedbeds; adjusting the planting distance and seedling amount of transplanting machinery according to the variety type to achieve precise cultivation; field management needs to strengthen the supporting ditch system to reduce drainage and waterlogging, timely and appropriately fertilize according to the growth process and seedling growth of rice, and adopt comprehensive control measures of ecological regulation and scientific medication for the prevention and control of diseases and pests such as sheath blight, rice blast disease, rice planthopper, and stem borer; timely use machinery for harvesting, and pay attention to moisture and mold prevention during storage. Corresponding promotion strategy includes strengthening publicity and guidance, providing financial support, etc., to motivate planting subjects; keeping up with the trend of technological development, improving technical points, and implementing key technologies; constructing high-yield demonstration area, demonstrating the application of high-yield and high-efficiency cultivation techniques; carrying out on-site observation, technical lectures, and skill competitions to strengthen technical training. This article provides a reference for the promotion and application of high-quality and high-yield rice cultivation techniques in related rice growing areas such us Southern Jiangsu Province.

To investigate the absorption and utilization of fertilization between single season rice fields under different fertilization methods, Guanliangyouhuazhan was used as the material, 9 different fertilization treatments were set up (PK, conventional fertilization nitrogen free zone; NK, conventional fertilization in phosphate free areas; NP, conventional fertilization in potassium free areas; NPK, conventional fertilization in the entire application area; PK1, deep lateral fertilization in nitrogen free areas; NK1, deep lateral fertilization in phosphate free areas; NP1, deep lateral fertilization in potassium free areas; NPK1, deep lateral fertilization in the entire application area; blank area, no fertilization), to determine the effects of each treatment on rice agronomic traits, yield, and fertilizer utilization efficiency. The results showed that under the same fertilizer type and quantity conditions, the ear length, total number of grains per ear, and seed setting rate in the mechanical side deep fertilization area were higher than those in the conventional fertilization area. The NPK1 treatment had the highest plant height, ear length, total number of grains per ear, and seed setting rate. Compared with conventional fertilization, mechanical side deep fertilization had increased grain yield at the same fertilization level; the highest grain and stem leaf yield was achieved with NPK1 treatment. The utilization rates of nitrogen, phosphorus, and potassium fertilizers in conventional fertilization were 36.95%, 31.07%, and 42.50%, respectively, while the utilization rates of nitrogen, phosphorus, and potassium fertilizers in mechanical side deep fertilization were 45.18%, 38.59%, and 49.99%, respectively. Overall, the application of mechanical side deep measurement for nitrogen, phosphorus, and potassium fertilizer application can achieve higher rice yields and higher fertilizer utilization efficiency.