Tiller number is a crucial agronomic trait that directly influences the grain yield per unit area of rice. Alternative polyadenylation (APA), an essential post-transcriptional regulatory mechanism, plays a significant role in rice growth and development by generating transcripts with varying 3ʹ untranslated region (3ʹUTR) lengths. However, the specific role of APA in rice tillering remains poorly understood. We employed nanopore cDNA sequencing and tandem mass tag proteomics to analyze tiller axillary buds at different developmental stages in rice. Our findings revealed that genes at the early stages of tillering (effective tillering) tend to utilize longer transcripts, whereas those at the later stages (ineffective tillering) favor shorter transcripts. APA-related genes at both the effective and ineffective tillering stages are enriched in known rice tillering-associated pathways, such as the terpenoid backbone biosynthesis pathway and the carotenoid biosynthesis pathway. Additionally, APA-related genes at the ineffective tillering stage are further enriched in pathways such as leaf and organ senescence. The results demonstrate that APA-mediated gene length variation regulates rice tillering in a spatiotemporally specific pattern, and APA further impacts the protein abundance of genes involved in tillering. Genes that utilize the distal AAUAAA signal and produce longer transcripts exhibit stronger expression than those using the proximal signal, while genes using the proximal AAUAAA signal and generating shorter transcripts show stronger expression than those using the distal signal. This study clarifies the regulatory patterns of APA in rice tillering, laying a molecular foundation for the potential breeding of rice with ideal plant architecture.

Alternative polyadenylation (APA) is a widespread post-transcriptional regulatory mechanism in eukaryotes that modulates gene expression by generating transcript variants. The development of young panicles in rice is a critical stage that determines grain number and weight. However, the regulatory mechanisms and inheritance patterns of APA during this process remain poorly understood. In this study, full-length isoform sequencing (Iso-seq) and metabolome were employed to investigate APA dynamics in the young panicle of hybrid rice variety Wufengyou T025 and in parent lines, Wufeng B and Changhui T025. This analysis revealed that approximately 80% of genes possessed two or more polyadenylation (pA) sites. These APA genes were predominantly enriched in the pathways associated with rice spikelet development, including response to external photoperiod changes, energy production and transportation, protein signal exchange, and amino acid metabolism. Notably, transcripts with a shortened 3'-untranslated region (3'UTR) exhibited elevated expression levels of their corresponding genes, suggesting that APA plays an important role in modulating gene expression. Furthermore, the variable 3'UTR of the 25% differentially expressed APA genes contained numerous miRNA binding sites, including osa-miR1848 and osa-miR5075, which are known to influence spikelet development. In the offspring, the expression levels of core APA factors during young panicle development were generally downregulated compared to the parental lines. Additionally, metabolomic analysis identified 209 and 164 differentially abundant metabolites in the offspring relative to Wufeng B and Changhui T025, respectively. Intriguingly, some of the enriched metabolic pathways overlapped with those of differentially expressed APA genes, implying that APA may influence small-molecule metabolites in pathways related to spike development. Collectively, these findings are valuable for understanding the regulation of APA and its genetic basis in young panicle development, offering new insights into the molecular mechanisms underlying this critical development stage.

The seedling stage is critically important for the development of rice plants, and rapid shoot growth has a major effect on plant morphology and yield potential. In this study, we identified a major and stable quantitative trait loci (QTL), qSL10, on chromosome 10, that controls shoot growth during the seedling stage using a high-resolution genetic map of recombinant inbred lines (RILs). Through differential gene expression and sequence analysis, we identified the candidate gene OsSL10 within the qSL10 region. OsSL10 was differentially expressed in the shoots of rice varieties with varying shoot growth rates. Functional validation using CRISPR/Cas9-mediated knockout and overexpression lines confirmed that OsSL10 regulates shoot length; knockout lines showed reduced shoot growth, and the growth of overexpression lines was enhanced. These findings highlight that OsSL10 is a key regulator of seedling shoot development; OsSL10 provides a promising target for improving seedling vigor in rice. Furthermore, the identification of new QTLs for seedling growth provides valuable insights into the genetic mechanisms governing early rice development, as well as opportunities for the breeding of high-yielding rice varieties.

Background: Alternative polyadenylation (APA) is an important pattern of post-transcriptional regulation of genes widely existing in eukaryotes, involving plant physiological and pathological processes. However, there is a dearth of studies investigating the role of APA profile in rice leaf blight. Results: In this study, we compared the APA profile of leaf blight-susceptible varieties (CT 9737-613P-M) and resistant varieties (NSIC RC154) following bacterial blight infection. Through gene enrichment analysis, we found that the genes of two varieties typically exhibited distal poly(A) (PA) sites that play different roles in two kinds of rice, indicating differential APA regulatory mechanisms. In this process, many disease-resistance genes displayed multiple transcripts via APA. Moreover, we also found five polyadenylation factors of similar expression patterns of rice, highlighting the critical roles of these five factors in rice response to leaf blight about PA locus diversity. Conclusion: Notably, the present study provides the first dynamic changes of APA in rice in early response to biotic stresses and proposes a possible functional conjecture of APA in plant immune response, which lays the theoretical foundation for in-depth determination of the role of APA events in plant stress response and other life processes.

[Objective]The aim of this study was to explore the effects of nitrogen fertilizer management on rice yield and quality under rice shrimp rotation mode.[Method]Using Yexiangyou Mingyuesimiao and Nongxiang 42 as experimental materials,different nitrogen application mounts and ratios at different stages were designed.[Result]With a 15%or 30%reduction based on the conventional nitrogen application amount(195 kg/hm2),the yield of Yexiangyou Mingyuesimiao did not significantly decrease,while the yield of Nongxiang 42 significantly increased.When the ratio of basal fertilizer:tillering fertilizer:panicle fertilizer was 4∶4∶2,the number of grains per panicle,seed setting rate and 1 000-grain weight of Yexiangyoumingyuesimiao were the highest,and the yield was the highest.When the ratio of basal fertilizer:tillering fertilizer:panicle fertilizer was 5∶3∶2,the effective panicle number per unit area,grain number per panicle,seed setting rate and 1 000-grain weight of Nongxiang 42 were the largest,and the yield was the highest.With the decrease of nitrogen application rate,the milled rice rate of Yexiangyou Mingyuesimiao and amylose content was significantly increased,while the protein content was significantly reduced.The peak viscosity and breakdown viscosity showed a trend of first increasing and then decreasing,reaching their maximums with the nitrogen application amount of 165.8 kg/hm2.When the ratio of basal fertilizer:tillering fertilizer:panicle fertilizer was 4∶4∶2 for Yexiangyou Mingyuesimiao and 5∶3∶2 for Nongxiang 42,the milled rice rate,head milled rice rate,gel consistency,peak viscosity and breakdown viscosity were the highest,while chalky grain rate,chalkiness degree,and amylose content were the lowest.[Conclusion]Under the rice-shrimp rotation system,reducing nitrogen application rate by 15%-30%and applying nitrogen at a ratio of 4∶4∶2 or 5∶3∶2 is beneficial to rice nitrogen efficiency,high quality and high yield.

Cracking of Akebia trifoliata fruit at maturity is problematic for the cultivation of the horticultural crop, shortening shelf-life quality and compromising commercial value. However, the molecular mechanisms underlying this feature of A. trifoliata are not known. Genes involved in cell wall metabolism were identified by genome and transcriptome sequencing, which may play important roles in fruit cracking. One of the galactose metabolism related genes, β-galactosidase (AtrBGAL2), was identified in A. trifoliata, and overexpression (OE) of AtrBGAL2 resulted in early fruit cracking, higher water-soluble pectin contents, and lower acid-soluble pectin, cellulose, and hemicellulose content compared to the wild type. Whereas silencing of AtrBGAL2 in trifoliata by virus induced gene silencing showed opposite trends. The levels of AtrBGAL2 transcripts were 24.6 and 66.0-fold higher in OE A. trifoliata and tomato fruits, respectively, and the cell wall-related genes were also gradually greater than in control plants during fruit ripening. Whereas the expression levels of AtrBGAL2 was significantly down-regulated by 54.1 % and 73.7 % in gene silenced A. trifoliata and CRISPR/Cas9 tomato mutant plants, respectively, and cell wall-related genes were also significantly reduced. These results demonstrate that AtrBGAL2 plays important roles in regulating fruit cracking during fruit ripening.

The timely degradation of tapetum, the innermost somatic anther cell layer in flowering plants, is critical for pollen development. Although several genes involved in tapetum development have been characterized, the molecular mechanisms underlying tapetum degeneration remain elusive. Here, we showed that mutation in Abnormal Degraded Tapetum 1 (ADT1) resulted in overaccumulation of Reactive Oxygen Species (ROS) and abnormal anther development, causing earlier tapetum Programmed Cell Death (PCD) and pollen abortion. ADT1 encodes a nuclear membrane localized protein, which is strongly expressed in the developing microspores and tapetal cells during early anther development. Moreover, ADT1 could interact with metallothionein MT2b, which was related to ROS scavenging and cell death regulation. These findings indicate that ADT1 is required for proper timing of tapetum PCD by regulating ROS homeostasis, expanding our understanding of the regulatory network of male reproductive development in rice.

Abstract Background Late spring cold is a disastrous weather phenomenon that often occurs during the early rice seedling stage in southern China, which poses a significant threat to open direct seeding of early rice seedlings. We found the differences in growth recovery performance between rice varieties after low temperature stress, but the differences in recovery between roots and stems/leaves are still unclear. 12 ℃ low temperature treatment of 4 days was set to investigate the growth phenotype and physiological changes of rice seedling roots during rewarming, as well as Transcriptome and metabolome were analyzed. Results Root growth was significantly inhibited after low temperature stress. During the rewarming process, the root length recovered the fastest, followed by the number of main roots. The fastest growth recovery period was in the first 3 days of rewarming; overall, the growth rate of B116 was higher than that of B811. The content of H2O2 and MDA in the root system of B116 decreased faster than that of B811 during the recovery process. The activities of POD and SOD showed an initial increase followed by a decrease, and returned to the control level after 6 days for the two varieties; Transcriptome analysis showed that the differential genes were mainly enriched in plant endogenous signal transduction, MAPK signal pathway, nitrogen metabolism and other biological pathways; The differential metabolites mainly included organic acids and their derivatives, organic oxygen compounds, and lipids and lipid molecules. Correlation analysis between Transcriptome and metabolome showed that plant endogenous signal transduction, starch and sucrose metabolism were the main metabolic pathways, and the differential expression of auxin response factors AUX/IAA, ARF and sucrose synthase SUS4, SPS1 was related to root growth. Conclusion The recovery of rice seedling growth after low temperature stress is related to the rapid clearance of ROS, utilization of auxin, and rapid metabolism of sucrose. The root system recovers growth earlier than the aboveground part, and the root system should be the main response to the harm of late spring cold in production.

Late spring cold is a disastrous weather condition that often affects early rice seedlings in southern China, limiting the promotion of direct seeding cultivation. However, there are few reports on the effect of these events and on the growth recovery mechanism of rice root systems after rice seedlings are exposed to this stress. This study selected the strong-growth-recovery variety B116 (R310/R974, F17) and the slow-recovery variety B811 (Zhonghui 286) for direct seeding cultivation and exposed them to low temperature and low-light stress to simulate a late spring cold event in an artificial climate chamber. The treatment consisted of 4 days of exposure to a day/night temperature of 14/10 °C and a light intensity of 266 µmol m−2s−1 while the control group was kept at a day/night temperature of 27/25 °C and light intensity of 533 µmol m−2s−1. The results showed that 6 days after stress, the total length, surface area, and volume of B116 roots increased by 335.5%, 290.1%, and 298.5%, respectively, while those of B811 increased by 228.8%, 262.0%, and 289.1%, respectively. In B116, the increase in root fresh weight was 223.1%, and that in B811 was 165.6%, demonstrating rapid root recovery after stress and significant differences among genotypes. The content of H2O2 and MDA in the B116 roots decreased faster than that in the B811 roots after normal light intensity and temperature conditions were restored, and the activity of ROS metabolism enzymes was stronger in B116 roots than in B811 roots. The correlation analysis between the transcriptome and metabolome showed that endogenous signal transduction and starch and sucrose metabolism were the main metabolic pathways affecting the rapid growth of rice seedling roots after exposure to combined stress from low temperature and low light intensities. The levels of auxin and sucrose in the roots of the strong-recovery variety B116 were higher, and this variety’s metabolism was downregulated significantly faster than that of B811. The auxin response factor and sucrose synthesis-related genes SPS1 and SUS4 were significantly upregulated. This study contributes to an understanding of the rapid growth recovery mechanism in rice after exposure to combined stress from low-temperature and low-light conditions.

Low temperature and overcast rain are harmful to directly seeding early rice, it can hinder rice growth and lower rice biomass during the seedling stage, which in turn lowers rice yield. Farmers usually use N to help rice recuperate after stress and minimize losses. However, the effect of N application on the growth recovery for rice seedlings after such low temperature stress and its associated physiological changes remain unclearly. Two temperature settings and four post-stress N application levels were used in a bucket experiment to compare B116 (strong growth recovery after stress) with B144 (weak growth recovery). The results showed that the stress (average daily temperature at 12°C for 4 days) inhibited the growth of rice seedlings. Compared to the zero N group, the N application group’s seedling height, fresh weight and dry weight significantly increased after 12 days. In particular, the increases in all three growth indicators were relatively higher than that of N application at normal temperature, indicating the importance of N application to rice seedlings after low temperature stress. The antioxidant enzyme activity of rice seedlings increased significantly after N application, which reduced the damaging effect of ROS (reactive oxygen species) to rice seedlings. At the same time, the soluble protein content of seedlings showed a slow decrease, while the H2O2 and MDA (malondialdehyde) content decreased significantly. Nitrogen could also promote nitrogen uptake and utilization by increasing the expression of genes related to NH4+ and NO3− uptake and transport, as well as improving the activity of NR (nitrate reductase) and GS (glutamine synthetase) in rice. N could affect GA3 (gibberellin A3) and ABA (abscisic acid) levels by regulating the anabolism of GA3 and ABA. The N application group maintained high ABA levels as well as low GA3 levels from day 0 to day 6, and high GA3 levels as well as low ABA levels from day 6 to day 12. The two rice varieties showed obvious characteristics of accelerated growth recovery and positive physiological changes by nitrogen application after stress, while B116 generally showed more obvious growth recovery and stronger growth-related physiological reaction than that of B144. The N application of 40 kg hm-2 was more conducive to the rapid recovery of rice growth after stress. The above results indicated that appropriate N application promoted rice seedling growth recovery after low temperature stress mainly by increasing the activities of antioxidant enzymes and nitrogen metabolizing enzymes as well as regulating the levels of GA3 and ABA. The results of this study will provide a reference for the regulation of N on the recovery of rice seedling growth after low temperature and weak light stress.

稻谷的耐储性在种子生产保存和粮食储备中具有重要的意义.本研究以人工陈化的方法对15个三系杂交稻恢复系品种进行筛选,获得了繁11、繁12、繁31、繁32和繁38五个耐储性较好的品种.选择繁38与粳型恢复系繁26为亲本杂交获得F1代,构建了包含154个株系的双单倍体(double haploid,DH)群体.以2b-RAD简化基因组测序技术对亲本和群体中每个株系进行测序,并构建SNP标记遗传图谱.分析水稻在人工陈化10 d和15 d时与耐储藏相关的QTL.共检测到了6个与稻谷耐储性相关的QTL位点,分布于3号、5号、6号、11号和12号染色体上,LOD值介于3.4509～6.8036之间,可解释6.1575％～12.9979％的表型变异,加性效应在-6.7586％到6.1235％范围内.其中qSI-12位点在陈化10 d和陈化15 d两个条件下均能检测到.qSI-5a和qSI-6这2个位点只在陈化10 d时检测到,而qSI-3、qSI-5b和qSI-11这3个位点只在陈化15 d时检测到.此外,还检测到32对上位性互作位点.这些结果丰富了耐储性品种育种的遗传资源,为进一步精细定位耐储性相关的QTL奠定了基础.

To further understand the molecular mechanism for rice male reproduction, a rice male sterile mutant paa1 was screened from the rice mutant library generated by treatment with 60Coγ-rays. Genetic analysis revealed that paa1 is controlled by a single- recessive nuclear gene, and the anthers of the paa1 mutant were smaller than those of WT plants with a white color. Histological analysis demonstrated that the anthers of the paa1 mutant began to turn abnormal at the microspore stage after meiosis, with abnormal degradation of tapetum, deformed Ubisch bodies, and defective pollen exine. TUNEL assay results also confirmed the delay of tapetum PCD in paa1. Map-based cloning was performed for the PAA1 location. As a result, PAA1 was located in a 88-kb region at the end of chromosome 10, which comprises a total of seven candidate genes, and no genes related to anther development have been reported in this region. The results indicate that PAA1 is an essential gene in regulating tapetum development and pollen/microspore formation after rice meiosis.

: Plant architecture is a compound trait integrated with multiple morphological and physiological traits, and it is closely related to rice yield. Deciphering excellent plant architecture alleles or QTLs is of great significance for high-yield rice breeding. In this study, we constructed a set of Changhui 121/Koshihikari chromosome segment substitution lines (CSSLs) with the size of 208 in our laboratory. QTLs controlling plant height, flag leaf morphology, and tiller numbers were detected under three environments. A total of 35 QTLs for rice architecture were identified on 11 chromosomes except chromosome 9, and the range of the phenotypic variation explaining was 2.00%–22.86%. It was worth noting that qPH-1-1 , qFLW-6 , and qFLA-3 could be detected in three environments, among which qFLW-6 was a newly identified QTL of the flag leaf width. Phenotypic identification verified that the additive effects and environmental stability of the two locus alleles by the replacement lines carrying qPH-1-1 and sites. The results of this study laid the foundation for further fine mapping and cloning of QTLs for rice plant architecture and the molecular marker-assisted selection (MAS) in rice breeding.

制种是杂交水稻推广过程中最为重要的环节之一,实现杂交粳稻全程高效机械化制种对保证杂交粳稻的持续、健康、快速发展具有重要意义.总结和归纳了杂交粳稻机械化制种的研究现状,分析了现阶段杂交粳稻机械化制种发展中存在的主要问题,对杂交粳稻全程机械化制种进行探索与实践,并介绍了上海杂交粳稻全程机械化制种的关键技术.

使用5个转Bt基因水稻恢复系作为父本,以12个不育系作为母本,根据5×12(NCII)不完全双列杂交设计配制60个组合,分析了这些组合的9个稻米品质性状的配合力及遗传参数.结果表明:精米率主要受基因加性效应的影响,整精米率、垩白粒率、碱消值、胶稠度主要受基因非加性效应互作的影响;除精米率主要受母本影响外,其余8个性状均受双亲交互作用的影响;垩白粒率和垩白度在后代遗传中主要受基因遗传作用的影响,可以在早代直接选择.配合力方差分析结果表明:精米率、垩白度及碱消值受环境因素的影响较大;昌恢891T为一般配合力较好的父本,华1165S为一般配合力较好的母本;原香39A/昌恢891T、泰乡1209A/昌恢T025T、昌盛843A/昌恢T025T为较优的组合,其中原香39A/昌恢891T的特殊配合力的综合评价最好.

Objective To explore the yield formation and photosynthetic characteristics of restorer line Yazhan series hybrid combination of rice，the relationship between yield and yield components，and the contribution of photosynthetic related factors to yield，so as to provide technical support for the breeding of hybrid line restorer line and high-yield cultivation. Methods In this experiment，two restorer lines Yazhan and Huazhan were used as male parents，and eight sterile lines such as Nongxiang A were used as female parents.Eight groups of 16 hybrid combinations were prepared as experimental materials.Field planting and conventional water and fertilizer management were used to analyze the yield，composition factor，chlorophyll content，net photosynthetic rate and other factors of the hybrid combinations of the two restorer lines，so as to compare the characteristics of the two restorer lines and their differences in photosynthetic performance. Results The results showed that the yield of the other 6 hybrid combinations was higher than that of the corresponding Huazhan combinations except for the C Liangyou and Quanliangyou hybrid combinations，and the yield advantage of the hybrid combinations was generally stronger than that of the Huazhan combinations.Path coefficient analysis showed that the effective panicle number and 1 000-grain weight per panicle were the main factors affecting the yield formation of Yazhan series hybrid combinations，and the grain number and seed setting rate per panicle played a secondary role，and both reached a significant level.During the period from the tillering stage to the grain filling stage，the chlorophyll content of Yazhan and their hybrid combinations dropped faster than that of Huazhan and their hybrid combinations，but the absolute value of chlorophyll content was higher than that of Huazhan and their hybrid combinations all through to the filling stage，the net photosynthetic rate of Huazhan series hybrid combinations was higher than that of Yazhan in the earing stage，but in the tillering stage and filling stage，the net photosynthetic rate of Huazhan series combinations was generally lower than that of Yanzhan series hybrid combinations，which showed that in the filling stage higher net photosynthetic rate was the key to increased production.The differences in yield formation and mechanism of the combinations were also discussed from the perspective of sink-source relationship，photosynthesis and chlorophyll，and the research results were of certain reference significance for further breeding and improvement of the restorer lines，hybridization and high-yield cultivation of the hybrid combinations. Conclusion As a restorer line，Yazhan has a better combination advantage than Huazhan，and the yield of the hybrid combinations is higher than that of Huazhan.The cultivars with strong photosynthetic ability，tillering ability and late grouting ability should be selected for restorer line breeding.

为探究干旱条件下氮素运筹对双季超级稻晚稻的影响.选用超级杂交晚稻品种五丰优T025,于幼穗分化期正常和干旱条件下,进行氮素蘖肥(干旱前)与氮素穗肥(干旱后)重施处理,考查产量及有关生理生态指标,结果表明:干旱将导致水稻产量显著下降,幼穗分化期是晚稻水分亏缺敏感期;2种水分条件下,氮素蘖肥重施产量均显著高于穗肥重施处理,分蘖期是晚稻需氮关键期;干旱条件下氮素蘖肥重施处理的单株有效穗数和结实率高于穗肥重施处理,差异均达显著水平;干旱条件下相对于氮素蘖肥重施处理,氮素穗肥重施处理抽穗期和开花期的光合速率(Pn)、蒸腾速率(Tr)等光合指标不同程度提高,但茎、叶部位氮素及干物质转运率低,滞留严重,转运至穗部的氮素相对较低,叶片渗透调节物质含量下降,丙二醛(MDA)含量生育后期提高,同时硝酸还原酶(NR)与谷丙转氨酶(GPT)等氮代谢酶活性在旱后短期内呈现增高趋势.因此,水稻上存在一定的"以氮调水"效应,适当提高氮素蘖肥可在一定程度上减轻晚稻穗分化期干旱胁迫造成的产量损失.

苎麻是多年生作物,连作多年会导致苎麻败蔸、产量下降,甚至死亡等,严重影响苎麻产业的发展.试验以连作和非连作苎麻根际土壤为研究对象,采用Illumina MiSeq测序平台,对苎麻根际土壤细菌和真菌群落结构进行分析.结果 表明,细菌群落结构中厚壁菌门、变形菌门、酸酐菌门、放线菌门和拟杆菌门为苎麻根际土壤细菌的优势菌门,连作苎麻根际土壤主要细菌为厚壁菌门,占细菌总数的93.46％,而非连作苎麻根际土壤主要为厚壁菌门、变形菌门、酸杆菌门,分别占细菌总数的64.60％、13.70％、5.77％;真菌中子囊菌门和担子菌门为苎麻根际土壤的优势菌门,连作与非连作苎麻根际真菌的门类未发生改变,但是各门类的比率发生了改变;主成分分析表明,连作与非连作苎麻根际土壤微生物丰富度有明显不同.综上所述,与非连作苎麻比较,连作苎麻根际细菌和真菌群落结构以及多样性发生了改变,多样性呈现下降的趋势,且真菌群落的含量比率也发生较大的改变,因此,苎麻根际微生物群落结构和多样性的改变可能是导致苎麻连作障碍的主要因子之一.

为宜春地区羊肚菌高效栽培提供参考,通过对2018-2019年引种羊肚菌试验总结,介绍了菌种选择、播种、发菌管理、病虫害防治等关键技术.

[目的]为探究不同种植密度对群体自动调节能力差异型双季稻品种产量及其构成,抗倒伏能力及其稻田杂草发生的影响.[方法]以筛选到的群体自动调节能力强品种早稻湘早籼45(XZX 45)、晚稻五丰优T025(WFY T025)和群体自动调节能力弱品种早稻潭两优83(TLY 83)、晚稻天优华占(TYHZ)为材料,共设置3个处理:高密度(HD)、中密度(MD)和低密度(LD),进行不同种植密度大田试验.[结果]与自动调节能力弱品种相比,自动调节能力强品种在不同密度下产量增幅为2.34％～15.66％.分析表明自动调节能力强品种的产量稳定性能更优,主要归因于其有效穗数、每穗粒数和结实率动态平衡实现.茎秆倒伏特征结果表明,自动调节能力差异型品种倒伏指数随种植密度增大不同程度提高.其中,自动调节能力强品种的茎秆各节间茎粗和壁厚、弯曲力矩和抗折力下降幅度显著低于自动调节能力弱的品种,有利于植株保持较高水平抗倒伏能力.此外,稻田杂草发生结果表明,自动调节力差异型品种的田间杂草生长量随种植密度增大均不同程度降低.自动调节能力强品种有利于抑制田间杂草发生量.[结论]采用群体自动调节能力强的水稻品种,配以适宜种植密度,为传统水稻高产稳产及抗倒和稻鱼共作模式中防草栽培提供一种生态学视角.