刈割残茬对新麦草种子产量和产量构成的影响

禾本科种子收获后的残茬管理对次年的种子产量非常重要。研究了刈割残茬时间和留茬高度对新麦草 Psathyrostachys juncea次年种子产量和产量构成的影响。结果表明：不同刈割残茬时间和不同留茬高度显著影响单位面积生殖枝数和种子产量（P<0.05）。其中，收获后立即刈割处理和齐地刈割处理获得了最高的生殖枝数和种子产量。不同刈割残茬时间和留茬高度处理对生殖枝小穗数、小穗小花数、小穗种子数和千粒重影响不显著（P<0.05）。相关分析表明，在留茬高度处理和刈割时间处理条件下，新麦草的单位面积生殖枝数与种子产量之间存在显著的正相关关系（P<0.05)。

Effect of cutting stubble on seed yield and yield components of Russian wildrye

Post harvest stubble management is essential for optimizing grass seed yield in next year.The field experiment was designed to evaluate the effects of cutting time and stubble height on seed yield and seed yield components of Russian wildrye(Psathyrostachys juncea).The results indicated that the treatments of cutting time and stubble height significantly affected the number of fertile tillers per square meter and seed yield.The maximums of fertile tillers and seed yield were obtained with the treatments of cutting stubble immediately after harvesting and ground level stubble height.The effects of cutting time and stubble height on spikelets per fertile tiller,florets per spikelet,seeds per spikelet,and 1000-seed weight were not significantly different(P>0.05).Correlation analysis revealed a consistent positive relationship between the number of fertile tillers per square meter and seed yield under the treatments of stubble height and cutting time.