不同施氮水平对麦茬复种饲料油菜生长性状的影响

通过田间小区试验，研究了不同施氮水平对麦茬复种饲料油菜不同生育期株高、鲜重、干重、叶面积指数、相对生长率、净同化率和作物生长率的动态变化规律，为该种植模式推广提供理论支撑。结果表明，麦茬复种油菜不同生育期地上生物产量的累积规律为幼苗期缓慢，蕾薹期最快，开花后减缓，基本符合“S”型生长曲线。增施氮肥能极显著提高复种油菜地上部干重、鲜重及其日生长量，以1000kg／hm^2施氮处理为最优产量施肥设计，干重、鲜重与其日生长量的累积规律呈极显著性正相关关系（r=0．967）。增施氮肥能明显提高或改善复种油菜株高、叶面积指数、相对生长率以及群体同化率和生长率，高氮肥水平更有利于油菜干物质积累和群体形态结构建成，达到适时丰产。

Effect of Different Nitrogen Level on Growth Properties with Wheat/Silage Rape Multiple Cropping

In this paper,a field experiment was conducted in Lanzhou and Wuwei China to study the effects of applying rape planting different nitrogen fertilizer on dynamic change trends of different growth stages plant height and dry weight and fresh weight and leaf area index and relative growth rate and net assimilation rate and crop growth rate of wheat stubble multiple cropping rape.The study provided scientific basis to spread pattern of wheat/silage rape multiple cropping.The results of Lanzhou experiment showed that aboveground organism yield accumulation rules can be described by "S" developing curve that was the seedling stage slower heightening and the buds stage quickest heightening and again slower heightening after blooming stage on wheat stubble multiple silage rape at different development stages.Increasing N fertilizer significantly increased dry weight and fresh weight along with their daily growth rate of multiple-cropping silage rape with wheat,moreover,1 000 kg/hm2 N fertilizer treatment was a the best yield project.Aboveground organism yield accumulation rules of dry weight and fresh weight along with their daily growth rate had obviously significant positive interrelated relation(r=0.967).Increasing N fertilizer obviously improved plant height and leaf area index and relative growth rate and net assimilation rate and crop growth rate of wheat stubble multiple cropping rape.Higher N fertilizer treatment still hastened dry-matter accumulation and colony-configuration morphogenesis to increase organism yield with timely harvest.