一次性减量施用控释肥对棉花群体冠层结构及产量构成的影响

【目的】 分析施用一次性减量控释肥与常规肥料对棉花群体冠层结构及棉花产量的影响,研究一次性减量施用控释肥对棉花化肥减施增效的作用,为棉花化肥减施增效技术提供研究基础。【方法】 采用多重复田间试验,利用CI-110等仪器研究施用不同用量的控释肥和常规肥料条件下,棉花冠层结构、光合性能、产量及其构成因子等参数变化。【结果】 一次性减量施用控释肥能保持棉花中后期较高的叶面积指数、提高中下层透光性、增强光能截获能力、减少群体漏光损失,延缓叶片老化和光合功能衰退速率。各处理棉花盛花期、吐絮前期LAI 与棉花总成铃数、单铃重及产量显著或极显著相关,盛铃期与棉花僵烂铃比重极显著相关。研究一次性减N₂5%施用控释肥处理比一次性全量施用控释肥处理平均增产2.89%、比全量施用常规肥料处理平均增产5.53%、比减N 25%施用常规肥料处理平均增产14.89%、比不施氮肥对照平均增产50.96%。【结论】 一次性减量施用控释肥可以构建合理的棉花群体冠层结构,增加棉花单株成铃数及产量,减少氮肥投入量,提高肥料利用率;一次性减N 25%施用控释肥(225 kg/hm²)为安徽省沿江棉区杂交棉适宜的氮肥用量。

Effects of One-off Decreasing Controlled-release Fertilizer Application on Cotton Canopy Structure and Yield Components

【Objective】 The study aims to analyze the effects of one-off decreasing controlled-releasefertilizer and conventional fertilizer application on cotton canopy structure and yield components and study the effect of one-off decreasing controlled-release fertilizer applicationon fertilization reduction and efficiency improvement in the hope of providing a theoretical basis for the fertilization reduction and efficiency improvementtechnologies.【Method】 Multiple field trial was conducted, CI-110 and other instruments were used to study the parameters of cotton canopy structure, photosynthetic, yield and yield components under one-off decreasing controlled-release fertilizer and conventional fertilizer application with different amounts.【Result】 one-off decreasing controlled-release fertilizer application could keep the higher leaf area index in the primary and late stage of cotton, improve the light transmittance of the middle and lower layers, enhance the PAR interception ability, and reduce the penetration loss of PAR in communities, delay leaf senescence and the photosynthetic function decline in leaves. LAR of different treatments in full-bloom stage and early boll opening stage was very significantly correlated with bolls number, boll weight and the cotton yield, and very significantly correlated with boll rot in multi-boll stage. In this study, the treatment of one-off decreasing 25% N of controlled-release fertilizer application increased yield by 2.89% compared with one-off total controlled-release fertilizer application, increased yield by 5.53% than conventional fertilizer application, increased yield by 14.89% than decreasing conventional fertilizerapplication, and increased yield by 50.96% than no N fertilizer application.【Conclusion】 One-off decreasing controlled-release fertilizer application can build a reasonable cotton canopy structure, increase boll number per plant and yield, decrease nitrogen fertilizer consumption, and improve the nitrogen use efficiency. The test results suggest that one-off decreasing 25% N of controlled-release fertilizer application (225 kg/hm²) is most suitable for hybrid cotton in cotton area along Changjiang River in Anhui Province.