Rice blast, caused by the fungal pathogen Magnaporthe oryzae, is among the most devastating rice diseases worldwide. During infection, M. oryzae deploys an arsenal of effectors into rice cells, altering their physiology and metabolism, and suppressing immune responses to facilitate colonization. A thorough understanding of M. oryzae effectors and their interaction mechanisms with rice holds significant potential to inform strategies for rice blast control. This review summarizes recent advances in elucidating the mechanisms of effector secretion into rice cells, the intricate regulatory mechanisms of effector-mediated rice blast resistance, and the classification of M. oryzae effectors. Additionally, it discusses the current challenges in effector research and outlines future research directions, aiming to provide a reference for the prevention and management of rice blast caused by M. oryzae.

The rational utilization of crop straw is of great significance to sustain agricultural development, and remarkable progress has been made in the comprehensive utilization of crop straw in China. Returning straw to fields is an effective method for utilizing straw resources, positively impacting grain productivity and promoting a virtuous cycle in soil health. At the same time, returning straw to fields alters the soil characteristics of paddy fields, which in turn changes the composition and activity of soil microorganisms, ultimately affecting greenhouse gas emissions. This work reviewed the effects and mechanisms of straw tillage, no-tillage mulch, and carbonization on soil characteristics and greenhouse gas emissions in paddy fields. It summarized measures for managing water and fertilizer under straw tillage conditions and discussed existing problems and future research priorities.

The rice planthoppers, including the brown planthopper, white-backed planthopper, and small brown planthopper, are major threats to global rice production. To combat these pests, rice has evolved defense mechanisms, including antibiosis, antixenosis or non-preference, and tolerance. In response, rice planthoppers have developed various adaptive strategies, such as possessing a complex chemosensory system to detect different chemicals, secreting salivary proteins that finely regulate plant defense responses, detoxifying harmful substances through gut-specific enzymes, enhancing adaptability to ecosystems via symbiotic bacteria, and exhibiting wing polyphenism to modulate growth and development according to the nutritional status of the host plant. Based on the latest scientific discoveries on the adaptation mechanisms of rice planthoppers to rice resistance, this paper summarized the genes for rice resistance to planthoppers and the virulence mechanisms of planthoppers. The review focuses on the areas of chemical communication between rice and planthoppers, salivary components, detoxification enzymes, symbiotic bacteria, and wing dimorphism regulation. Studies have shown that biotype evolution of brown planthopper and the loss of resistance in pest-resistant varieties after their promotion remain major challenges in pest management. Future research should prioritize elucidating the molecular mechanisms of adaptability of brown planthoppers and develop new, more effective management strategies to achieve long-term goals and sustainable control of brown planthopper. Additionally, this paper discusses how modern biotechnologies such as genomics, transcriptomics, metabolomics, and epigenetics can be used to deepen the understanding of the interaction network between brown planthoppers and rice, and how this knowledge can be used to formulate more effective pest management strategies.

【Objective】Lesion mimic mutants are ideal materials to study the mechanisms of plant cell death and disease resistance, offering new strategies for plant disease resistance breeding.【Method】The lm52 mutant gene was cloned by the map-based cloning method, and the function of the candidate gene was verified by CRISPR/Cas9 knockout technology. Meanwhile, the resistance of lm52 to multiple rice pathogens and the possible resistance mechanisms were analyzed.【Result】The mutant lm52 gradually developed progressive brown spot lesions from the 4th leaf stage, with whole leaf necrosis at maturity stage. A single base mutation (G₁₄₄₀A) on the ATPase encoding gene LOC_Os06g03940 caused the lesion mimic phenotype of lm52. lm52 is characterized by significantly enhanced resistance to blast, sheath blight and bacterial blight, which was found to be related to the overaccumulation of ROS and the activation of defense-related genes.【Conclusion】The mutation of the ATPase gene LM52 enhances rice resistance against diverse pathogens, and provides potential target genes for molecular breeding of rice disease resistance.

【Objective】This study aims to investigate the functional role of the rice eukaryotic translation initiation factor OseIF6.2 in rice growth and development using a reverse genetics approach, thereby laying a foundation for further exploration of the functions of OseIF6.2.【Method】First, bioinformatics methods were employed to perform multiple sequence alignment and a phylogenetic tree was constructed to analyze the evolutionary relationship between OseIF6.2 and eIF6 proteins in other eukaryotes. CRISPR/Cas9 gene editing technology was used to precisely edit the OseIF6.2 gene in rice (Nipponbare).Next, the expression levels of OseIF6.2 in different tissues of rice were detected using quantitative real-time PCR (qRT-PCR) technology. The precise localization of OseIF6.2 within cells was observed using a confocal laser microscope.Finally, the interaction between OseIF6.2 and its potential interacting protein, OseIF6.1, was validated using yeast two-hybrid (Y2H) and bimolecular fluorescence complementation (BiFC) assays. 【Result】Phylogenetic analysis revealed that OseIF6.2 is highly conserved among eukaryotic eIF6 proteins, underscoring its universal role in translation regulation.qRT-PCR results indicated that OseIF6.2 expression was relatively high in rice stems. Subcellular localization analysis using GFP-tagged OseIF6.2 in tobacco leaf cells showed fluorescence signals in both the nucleus and cytoplasm, confirming its dual localization.Additionally, compared to the wild type, the oseif6.2 mutant exhibited significant reductions in grain length, grain thickness, and 1000-grain weight. Both Y2H and BiFC experiments confirmed a direct interaction between OseIF6.2 and OseIF6.1【Conclusion】In summary, OseIF6.2, a eukaryotic translation initiation factor in rice, plays a crucial role in regulating grain morphology, further highlighting its importance in rice growth, development, and grain formation.

【Objective】Rice (Oryza sativa L.) is a crucial staple crop globally. Its production is severely threatened by rice blast disease. Identifying resistance materials and analyzing resistance genes are essential for understanding the mechanisms behind rice blast resistance. This study aims to systematically generate and identify genetic materials of the rice blast resistance gene OsDR8, conduct haplotype and evolutionary analyses to select superior haplotypes, and investigate their subpopulation differentiation. These efforts will lay a theoretical basis for the application of OsDR8 in rice blast resistance breeding programs.【Method】We developed transgenic lines overexpressing the OsDR8 gene and its knockout mutants. We conducted rice blast resistance assays on the overexpression lines, homozygous knockout lines, and corresponding wild-type materials using Magnaporthe oryzae isolates RO1-1 and RB22. Meanwhile, haplotype and evolutionary analyses of the OsDR8 gene were conducted based on the rice super pan-genome variation map.【Result】Disease symptom observation and disease resistance evaluation indicated that knockout mutants had significantly larger lesion sizes and a higher proportion of diseased leaf area compared to the wild-type. In contrast, the overexpression lines showed reduced lesion sizes and a lower proportion of diseased leaf area. Combined with haplotype and evolutionary analyses, the results indicated that materials of the superior haplotype Hap2 show stronger disease resistance, with 95.52% of the indica rice subpopulation being the Hap2 haplotype.【Conclusion】The OsDR8 gene positively regulates resistance to rice blast, and that the superior haplotype Hap2 may be associated with stronger resistance in indica rice.

【Objective】Rice blast is a worldwide disease caused by filamentous ascomycete fungus Magnaporthe oryzae, which seriously affects the quality and yield of rice. At present, cultivating and planting disease-resistant varieties is the most economical and effective strategy to control rice blast, and the mining and utilization of blast-resistance genes is the key to disease-resistant rice breeding. In this study, Kangfeng B (KFB), an elite maintainer line of indica hybrid rice with broad-spectrum resistance derived from Sanming Academy of Agricultural Sciences was used as the test material, and the Pi-kf2(t) gene in which was used to conduct resistance spectrum analysis, cloning and functional verification.【Method】For resistance spectrum analysis, KFB (Pi-kf2(t)), 75-1-127 (Pi9), C101A51 (Pi2), IRBLzt-T (Piz-t), EBZ (Pi50) and GM-4 (Pigm) seedlings were inoculated with 100 rice blast isolates from different regions of China during 3-4 leaf stages; The expression analysis of two Pi-kf2(t) candidate genes, Pi-kf2(t)-NBS2 and Pi-kf2(t)-NBS4, were determined by semi-quantitative reverse-transcription PCR (RT-PCR) and quantitative real-time PCR (qRT-PCR); Pi-kf2(t) gene was cloned by homologous cloning strategy and a phylogenetic tree was constructed to investigate the possible relationships between Pi-kf2(t) and Pi9, Pi2, Piz-t, Pi50, and Pigm proteins in evolutionary history. Moreover, sequence and expression analyses revealed Pi-kf2(t)-NBS2 as the candidate Pi-kf2(t) gene, which was verified by transgenic complementation test.【Result】The resistance spectrum of Pi-kf2(t), Pi9, Pi2, Piz-t, Pi50 and Pigm were 93%, 90%, 91%, 78%, 95% and 96%, respectively. The candidate gene Pi-kf2(t)-NBS2 exhibited a high expression level in the leaves of KFB seedlings and was not induced by isolates of rice blast, which showed a constitutive expression, while Pi-kf2(t)-NBS4 exhibited an extremely poor expression. Multiple amino acid sequence alignment analysis revealed that there were 45, 31, 34, 2, and 2 amino acids differences between Pi-kf2(t)-NBS2 and Pi9, Pi2, Piz-t, Pi50, and Pigm proteins, respectively. Phylogenetic tree analysis showed that Pi-kf2(t)-NBS2 exhibited a closer genetic relationship and a higher homology with Pi50 and Pigm. Furthermore, genetic complementation test verified that the candidate gene Pi-kf2(t)-NBS2 was the Pi-kf2(t).【Conclusion】The rice blast-resistance gene Pi-kf2(t) is a novel member of the Pi2/Pi9 multigene family. This work provided a theoretical basis for further disease resistance mechanism study of Pi-kf2(t), and also provided an important germplasm resource for rice blast-resistance breeding.

【Objective】The broad-spectrum resistance gene PigmR has important breeding value for the genetic improvement of rice blast resistance. Developing kompetitive allele specific PCR (KASP) markers based on its coding region variation sites is beneficial for improving the accuracy and efficiency of PigmR utilization in breeding.【Method】This study identified single nucleotide variations in the coding region of PigmR through sequence alignment, developed the KASP molecular marker PigmR-K, conducted genotype analysis using rice varieties and F₂ segregating populations, combined these results with rice blast symptom identification, and carried out molecular marker assisted selection breeding to verify the precision and efficiency of this marker.【Result】Based on an A-to-C mutation at position 2503 in the PigmR gene coding region sequence, a precise and efficient PigmR genotyping technology system based on KASP markers was established. The genotyping of 159 rice varieties, 270 F₂ individuals, and 247 BC₁F₃ population lines demonstrated that PigmR-K reliably distinguished the homozygous resistant, homozygous susceptible and heterozygous genotypes of PigmR. These results were completely consistent with disease symptoms from artificial panicle blast inoculation.【Conclusion】The KASP marker PigmR-K developed based on the variation site of on the coding region has advantages such as precision and efficiency, which is beneficial for genetic improvement of rice blast resistance.

【Objective】This study aims to investigate the effects of combined salinity-drought stress on rice grain-filling characteristics and its relationship with yield formation.【Method】The study was conducted with conventional japonica rice cultivar Nanjing 9108, which is widely cultivated in the coastal saline soil of Jiangsu Province, China. The experimental design consisted of factorial combinations of salinity and drought stresses: salinity stress induded non-salinity (NS, salt concentration 0%) and high-salinity stress (HS, salt concentration 0.3%); while drought regimes comprised well-watered (WW), moderate drought (MD), and severe drought (SD) treatments from jointing stage to heading stage.【Result】Compared with non-stress, 1) the yield reduction under salinity stress, drought stress, and combined salinity-drought stress was 36.8%, 13.7%−30.0%, and 60.3%−107.1%, respectively (two-year average). 2) the number of panicles per unit area, grains per panicle, seed setting rate, and the thousand-grain weight were all lower under single salinity stress, single drought stress, and combined salinity-drought stress, and the reduction was greater under combined salinity-drought stress; the panicle length, and grain weight and seed setting rate of superior and inferior grains showed a similar trend. 3) single salinity stress, single drought stress, and combined salinity-drought stress significantly reduced dry matter weight at jointing and heading and the accumulation of dry matter weight from heading to maturity, as well as leaf photosynthetic rate and SPAD value at 20 and 40 days after heading; the reductions under combined salinity-drought stress were greater than those under single salinity and single drought stress. 4) the maximum grain-filling rate and the mean grain-filling rate of superior and inferior grains were lower under single salinity stress, single drought stress, and combined salinity-drought stress, while the time to reach the maximum grain-filling rate and the effective grain-filling period of superior grains showed an increasing trend, and the differences in the time to reach the maximum grain-filling rate and the effective grain-filling period of inferior grains were smaller. The number of days in the early, middle, and late periods were greater under single salinity stress, single drought stress, and combined salinity-drought stress, while lower for the mean grain-filling rate and grain-filling amount. 5) single salinity stress, single drought stress, and combined salinity-drought stress treatments reduced the activities of key starch synthesis enzymes in grains, especially for AGPase and GBSS enzymes.【Conclusion】This study demonstrats that the grain-filling rate and key starch synthesis enzyme activities of superior and inferior grains decreased significantly and the grain-filling characteristics of superior and inferior grains were deteriorated under single salinity stress, single drought stress, and especially combined salinity-drought stress. The inhibitory effects of combined salinity-drought stress on the grain-filling rate, grain-filling amount of superior and inferior grains, and grain yield were greater than single salinity and drought stress.

【Objective】This study investigated the effects of different nitrogen types of basal fertilizer on root function, photosynthetic capacity, nitrogen metabolism enzyme activity, grain yield, and nitrogen use efficiency of ratooning rice, aiming to provide a theoretical basis for high-yield and efficient production of ratooning rice in the Jianghan Plain.【Method】A two-year field experiment (2020-2021) was conducted at the Experimental Station of Yangtze University in Jingzhou City, Hubei Province. Four basal fertilizer treatments were applied: no nitrogen application (N0), urea (CK), 50% controlled release urea + 50% urea (T1), and 50% livestock manure organic fertilizer + 50% urea (T2). The N0 treatment received no nitrogen throughout the rice growth season, while other fertilization periods maintained consistent nitrogen types and amounts across CK, T1, and T2. Root dry weight, root activity, leaf area index (LAI), and net photosynthetic rate (P_n) were measured at critical growth stages. Activities of nitrogen metabolism enzymes were determined at heading stages of both main and ratooning seasons. Yield components and nitrogen use efficiency parameters were analyzed.【Result】The T2 treatment exhibited the highest root dry weight, root activity, LAI, and P_n. Activities of nitrogen metabolism enzymes and yields for both seasons followed the order: T2 > T1 > CK > N0. Compared with N0, total rice yield increased by 75.13%, 97.37%, and 137.86% under CK, T1, and T2 treatments, respectively. Relative to CK, T1 and T2 significantly improved grains per panicle, seed-setting rate, and 1000-grain weight. Nitrogen recovery efficiency, agronomic nitrogen use efficiency, and partial factor productivity of nitrogen ranked as T2 > T1 > CK.【Conclusion】Replacing 50% conventional urea with livestock manure organic fertilizer as base fertilizer enhanced root function, photosynthetic capacity, and nitrogen metabolism enzyme activities, resulting in the highest yield and nitrogen use efficiency. This strategy represents an optimal nitrogen management approach for ratooning rice production in the Jianghan Plain.

【Objective】This study aims to clarify the effect of phosphorus fertilizer dosage on grain yield, phosphorus accumulation, phosphorus fertilizer utilization, and economic benefits of direct-seeded rice in Hubei Province. It provides a theoretical basis for the scientific fertilization of direct-seeded rice in the region.【Methods】Four phosphorus fertilizer application rates (0, 45, 90, and 135 kg/hm²)were established in a multi-site experiment across counties (cities and districts) in the major rice-producing areas of Hubei Province. The grain yield, phosphorus content, phosphorus accumulation, phosphorus fertilizer utilization, and economic benefits of rice under different phosphorus fertilizer dosages were comparatively analyzed.【Results】Compared to the zero phosphorus treatment (0 kg/hm²), the phosphorus fertilizer dosages of 45, 90, and 135 kg/hm² at each experimental site increased the grain yield by 0.18−1.80 t/hm², 0.30−3.24 t/hm², and 0.60−2.61 t/hm², respectively, with average increases of 9.15%, 16.08%, and 18.24%.Additionally, the aboveground phosphorus accumulation of rice increased by 1.57−9.18 kg/hm², 2.67−12.77 kg/hm², and 4.16−15.06 kg/hm², with average increases of 29.14%, 44.92%, and 53.60%, respectively. Overall, rice yield increased with the phosphorus fertilizer dosage in the range of 0−90 kg/hm², and there was no significant difference in rice yield when the phosphorus fertilizer dosage exceeded 90 kg/hm².With the increase in phosphorus fertilizer dosage, rice phosphorus accumulation, production value, and net income followed a trend of increasing and then stabilizing, while partial productivity of phosphate fertilizer, agronomic utilization rate, recycling rate, and production-to-input ratio decreased with higher phosphorus fertilizer dosages. An interaction was observed between phosphorus fertilizer dosage and experimental location regarding yield, phosphorus accumulation, phosphorus fertilizer utilization, production value, and net income of direct-seeded rice.【Conclusion】Appropriate phosphorus fertilizer dosage can significantly improve the grain yield, aboveground phosphorus accumulation, and phosphorus fertilizer utilization of direct-seeded rice. Considering yield, phosphorus accumulation, fertilizer utilization, and economic benefits, the recommended dosage of phosphorus fertilizer for direct-seeded rice in Hubei Province is 58−104 kg/hm², with an average of 82 kg/hm². The theoretical maximum yield can reach 6.97−12.18 t/hm², with an average of 9.14t/hm², which can ensure rice yield while minimizing nutrient loss and reducing environmental pollution.

【Objective】To explore the application method and effects of Piriformospora indica in rice production.【Method】Indica lines Taiyou 203 and ZY246 were employed in this study, with a standard dosage of 1 g/L P. indica solution applied. Additionally, grey relational analysis methods were utilized to comprehensively evaluate the impact of three treatments—P. indica, compound fertilizer, and their combination—on the quality of rice seedlings for mechanical transplanting.【Result】The combined application of P. indica and compound fertilizer significantly enhanced seedling growth, increased seedling biomass, chlorophyll content, root system activity, and nitrate reductase activity. Furthermore, it promoted the expression of growth-related genes.【Conclusion】These findings deepen the understanding of the mechanisms by which P. indica promotes rice growth and provide a theoretical basis and practical guidance for the application of P. indica in rice production, particularly during the seedling nursery phase for mechanical transplanting.