不同施肥量对北疆高产棉花冠层结构、养分吸收和产量构成的影响

为了对膜下滴灌棉花高产高效栽培的施肥措施提供理论依据,采用小区实验,研究不同氮、磷、钾施用量对棉花冠层结构、养分吸收和产量的影响。结果表明：随着施肥量的增加棉花叶面积指数在盛铃期以前显著增加,盛铃期及以后叶面积指数呈现先增加后减少的趋势,其峰值出现在盛铃期。在盛铃期植株氮、磷、钾的含量随着施肥量的增加而增加。随着施肥量的增加棉花平均叶簇倾角变大,株型变的紧凑,但施肥量过多会导致棉花群体叶面积增加过多,群体散射辐射与直射辐射透过系数小,冠层结构不良,削弱了棉花个体发育,造成单株成铃数和单铃重降低。随施肥量的增加棉花产量有显著差异,表现为先增加后减少的趋势。表明施肥过量或过低棉花均难以获得高产,对于北疆地区棉花高产栽培建议棉花滴灌施肥量为尿素639.60 kg/hm^2、磷酸一铵177.67 kg/hm^2、硫酸钾施148.06 kg/hm^2。

Effect of Different Fertilizer on Canopy Structure, Nutrient Absorption and Yield Formation of High-yield Cotton in North Xinjiang, China

In order to offer theoretic basis for the fertilization techniques of high-yield cotton cultivation underfield drip irrigation,a block experiment was conducted to study the effect of different nitrogen, phosphorus andpotassium fertilizer on canopy structure, nutrient absorption and yield of cotton. The results showed that： cottonLAI（leaf area index） was significantly increased with the increase of fertilizer before full boll stage, itincreased first and then decreased at full boll and boll opening stage and attained maximum LAI at full bollstage. The content of nitrogen, phosphorus, potassium increased with the increase of fertilizer in cotton plantsat full boll stage. With the increase of fertilizer, MFIA became large and plant type became compact, butexcess fertilization could lead to canopy LAI increasing too much, smaller TCDP and TCRP, bad canopystructure, weakened cotton individual development, and resulted in the reduction of boll number per plant andboll weight. Cotton yield had significant difference between different fertilization treatments and increased atfirst and then decreased, indicating that excess or low fertilization was not suitable for obtaining high yieldcotton. For high- yield cultivation of cotton in North Xinjiang drip fertigation was suggested： urea639.60 kg/hm2, monoammonium phosphate 177.67 kg/hm2, potassium sulphate 148.06 kg/hm2.