追施氮肥对小偃22生物学特性及产量的影响

Effect of Nitrogen Topdressing on Biological Characteristics and Yield of Wheat Xiaoyan 22

为给小偃22及其同类型品种的大面积推广种植提供施肥依据，以小偃22为材料，在拔节期和孕穗期单施或同时追施不同量的氮肥，研究了追施氮肥对其产量及其构成因素和主要生物学特性的影响。结果表明，不同生育期追施氮肥均对小偃22有极显著的增产作用，追施氮肥处理的平均单产比对照提高11.3%。追施氮肥对产量的效应与追施氮肥时期和追施氮肥量有关。拔节期追施氮肥增产幅度比孕穗期高2-4个百分点。以拔节期37.5 kg/ha与孕穗期75 kg/ha增产幅度最大，比对照增产15.4%。追施氮肥对产量构成因素的影响主要表现在提高成穗数和穗粒数两个方面，成穗数平均比对照提高11.5%，以孕穗期追施氮肥对成穗数影响最为明显；穗粒数平均比对照提高6.9%。追施氮肥可明显促进主茎节间的生长，节间总长比对照增加7%，追肥处理对不同部位节间的影响与追施氮肥时期和追施氮肥量有关。追施氮肥可使单株成穗数比对照提高11.4%。追施氮肥对功能叶面积的影响与叶位和蘖位及追施氮肥时间有关。

Xiaoyan22,a medium gluten wheat,was used to study the effects of different nitrogen topdressing levels on the yield,yield components and the main biological characteristics of wheat at jointing stage,booting stage and both at jointing and booting stage.The result showed that nitrogen topdressing had a significant effect on yield at different stages,and the yield increased 11.3% by nitrogen top dressing treatment.The effect of nitrogen topdressing on yield was closely related with the time and level of nitrogen fertilization,and the yields was 2-4 points of percentage higher at jointing stage than that at booting stage.The highest yield was obtained at 37.5 kg/ha at jointing stage and 75 kg/ha at booting stage,the yield was 15.4%higher than that of CK.The effect of nitrogen topdressing on the main component factors of yield was mainly on grain number per ear and number of ears per plant.The number of ears per plant was 11.5% higher than that CK and the grain number per ear was 6.9% higher than that of CK.The effects of nitrogen topdressing on ear had most significant at booting stage.The nitrogen topdressing promote the growth of main stem inter-node markedly and made the total length of inter-node 7% longer than that of CK,and the effect of different stem inter-node was related with the nitrogen topdressing time and level of nitrogen fertilization.Moreover,nitrogen topdressing could increase the number of ears per plant significantly,with 11.4% increase over that of control.The effect of nitrogen topdressing on the area of functional leaves was significantly related to leaf position and tiller position,as the time of nitrogen fertilizer was.