倒伏时期和倒伏程度对小麦产量的影响

Effects of Lodging Period and Degree on Wheat Yield

本试验结果表明:小麦生育中后期发生倒伏均会造成减产,倒伏时期对小麦产量的影响大于倒伏程度。从倒伏时期来看,处理间减产量由大到小依次为:灌浆始期>开花期>灌浆中期>灌浆后期,减产幅度分别为37.29%、29.36%、10.80%和4.26%。从倒伏程度来看,总体表现为倒伏越严重减产幅度也越大。穗粒数减少和千粒重降低是倒伏造成小麦减产的主要原因。开花期和灌浆始期平铺处理穗粒数分别比对照减少12.25%和10.04%,倾斜倒伏处理分别比对照减少4.92%和7.28%。灌浆始期倒伏对粒重的影响最大,灌浆中期和开花期次之,灌浆后期影响最小。除开花期外,同一倒伏时期内倒伏程度处理间千粒重差异不明显,产量差异不显著。因此,在小麦后期倒伏产量减损评估中,可以将不同倒伏程度的小麦产量损失进行合并分析,倒伏时期可作为评价小麦产量损失的主要依据。

The results showed that lodging during heading to late filling stage all could lead to yield loss . The effect of lodging period on wheat yield was higher than that of lodging degree .The yield losses caused by lodging at initial grain filling stage , anthesis stage , mid-filling stage and late filling stage were 37 .29%, 29.36%, 10.80%and 4.26%respectively.And the more serious the lodging was, the bigger the loss was. The yield loss was mainly due to the decrease of grain number per spike and thousand -grain weight .Com-pared with control , the grain number per spike of flat lodging treatment at anthesis stage and initial grain filling stage decreased by 12.25% and 10.04% respectively, and that of leaning lodging treatment decreased by 4 .92%and 7 .28%respectively .Lodging at initial grain filling stage had the biggest effects on grain weight , then the mid-filling stage and anthesis stage , the late filling stage had the least .Except for anthesis stage , there was no significant difference on thousand -grain weight and yield between flat lodging and leaning lodg-ing treatment at the same stage .The results suggested that at the assessment of wheat yield loss at the late de-velopmental stage , the grain losses caused by different lodging degrees could be integrated , and the lodging period could be regarded as the primary evaluation basis .