播期·密度和追施缓释肥对徐麦368产量及群体结构的影响

Effects of Sowing Date,Density and Topdressing Slow-released Fertilizer on Yield and Population Quality in Xumai 368

以徐麦368为供试品种,通过设置不同播期、种植密度和拔节孕穗肥施用方式互作试验,探究3因素对小麦群体生长发育特性和产量的协同调控机制。结果表明,播期是影响徐麦368产量最重要的因素,正常播期(10月10日)有利于该品种发挥产量潜力,且在播期10月10日、种植密度240万~360万/hm^(2)和返青期追施缓释肥(A1)条件下产量最高。产量、穗数、千粒重与各生育时期叶面积指数(LAI)、干物质积累量、花后干物质量、收获指数(HI)均呈显著或极显著正相关。适期播种(10月10日)和增加密度,有利于提高各生育期LAI、干物质积累量、拔节期高峰苗和成穗数,但晚播条件增大密度对群体的补偿能力是有限的。返青期施用缓释肥(A1)可有效促进分蘖成穗,提高生育中后期LAI,显著提高成穗数和千粒重,实现高产稳产。

Taking Xumai 368 as the research material,interaction test on sowing date,planting density and jointing-booting topdressing was carried out to research on their effects on their coordinate regulation of grain yield and population characteristics.Results showed that sowing date was the most important cultivation factor in the regulation of grain yield.The appreciate sowing date was 10th October in Xumai 368,and the highest yield achieved under the combination of 10th October,240×10^(4)-360×10^(4)/hm^(2)and A1(applying slow-released fertilizer at re-greening stage).Correlation analysis showed that grain yield,number of ears and 1000-grain weight were all positively linked to leaf area index(LAI)and dry matter accumulation in each growing stage,dry matter accumulation after anthesis,and harvest index(HI).In suitable sowing date and increasing density,the LAI and dry matter accumulation in each growing stage,dry matter accumulation after anthesis,the maximum number of stem and tillers and number of ears all improved,but these regulation effects were limited.Applying slow-released fertilizer at re-greening stage could increase earbearing tiller percentage and promote LAI during mid-late growing period,which was beneficial for number of ears and 1000-grain weight.