养分综合管理对寒地水稻抗倒伏性能的影响

【目的】研究养分综合管理与寒地水稻抗倒伏性能的关系,探明提高水稻抗倒伏能力的机制。【方法】采用田间小区试验方法,设置习惯施肥、优化施肥、传统高产施肥、优化高产施肥4个处理,通过养分综合管理形成不同产量群体,测定水稻茎秆物理性状、力学特性和茎秆碳氮比等指标。【结果】习惯施肥产量为8.55t·hm-2,通过优化施肥使水稻产量提高了11.6%,基部一、二节间长度分别降低了13%和6%(P5%),抽穗后30d的碳氮比显著增加,茎粗、茎壁厚度、叶鞘重和茎横截面积显著提高,茎秆抗折力提高,水稻倒伏指数降低了14.18%(P5%);与习惯施肥相比,传统高产施肥产量提高了15.2%,实现了水稻高产目标。通过养分进一步优化,水稻产量又增加了7.4%,基部一、二节间长度分别减少了12%和4%(P5%),抽穗后30d的碳氮比、茎粗、叶鞘重和茎横截面积显著提高,茎秆抗折力有增加趋势,倒伏指数降低了6.19%(P5%)。与优化施肥相比,优化高产施肥处理收获穗数增加了15.1%(P5%),产量增加了10.9%(P5%),倒伏指数两处理差异不显著。【结论】虽然优化施肥和优化高产施肥使水稻重心高度和株高增加,但是由于优化了水稻节间配置,降低了基部节间长度,提高了水稻茎秆碳氮比,增加了水稻茎粗和充实度,在增加水稻产量的同时,显著提高了水稻的抗倒伏能力。

Effects of Integrated Nutrient Management on Lodging Resistance of Rice in Cold Area

【Objective】 The relationship between integrated nutrient management and the lodging resistance of rice was studied to elucidate the mechanism underlying the lodging resistance of rice plant in cold area. 【Method】 A field experiment was conducted with 4 nutrition managements and the physical properties, mechanical features and carbon-nitrogen ratio of the stems of rice were analyzed. 【Result】 The yield of the farmers fertilization practice (FFP) was 8.55 t?hm-2. Optimal fertilization practice (OPT) increased the yield, reduced the length of the first and second internode of the basal stem by 11.6% (P＜5%), 13% and 6% (P＜5%), respectively, significantly increased carbon-nitrogen ratio, stem diameter, stem wall thickness, leaf sheath weight and area of cross section 30 d after heading, and reduced the index of lodging resistance by 14.18% (P＜5%). Compared to FFP, the yield of the farmers fertilization practice for high yield (FFP -H) was increased by 15.2% and achieved high-yield rice. Compared to FFP-H, the optimal fertilization practice for high yield (OPT-H) increased rice yield by 7.4%, the length of the first and second internode of the basal stem is reduced by 12% and 4% (P＜5%), separately, at the same time, carbon-nitrogen ratio, stem diameter, stem wall thickness, leaf sheath weight and area of cross section were significantly increased, and the index of lodging resistance was reduced by 6.19% (P＜5%) 30 d after heading. Compared to OPT, the harvest panicles of OPT-H was increased by 15.1% (P＜5%), yield was increased by 10.9% (P＜5%), but the index of lodging resistance between the two treatments was not significanty different. 【Conclusion】 OPT and OPT-H increased the height of gravity center and plant height, but reduced the distance of basal internode due to optimization of internode collocation of rice, and increased carbon-nitrogen ratio of rice stems and stem diameter, promoted stem substantiality, resulting in high grain yield and lodging resistance of rice plant.