秸秆覆盖对旱地冬小麦灌浆动态及产量的影响

Effect of straw mulching on grain filling dynamics of winter wheat and yield in dryland

为了研究不同秸秆覆盖量处理下冬小麦籽粒灌浆的动态及产量变化,在渭北旱塬设置秸秆覆盖量9000 kg/hm2(SM9)6、000 kg/hm2(SM6)3、000 kg/hm2(SM3)及无覆盖(CK)4个处理进行旱地冬小麦栽培试验。结果表明,在灌浆渐增期,不同处理的灌浆速率表现为:CK>SM3>SM6>SM9;速增期和缓增期灌浆速率大小为:SM3>SM6>CK>SM9。SM9灌浆持续时间长,较CK多6 d,SM6、SM3与CK灌浆持续时间近乎一致。在灌浆速增期和缓增期,覆盖处理的灌浆贡献率均大于CK,在渐增期则均小于CK。相对于CK而言,覆盖一年后3 000 kg/hm2处理提高了冬小麦产量,较CK显著增产5.9%,且速增期和缓增期灌浆速率保持较高水平。

A field experiment including straw mulching in different amounts was set in Weibei Loess Plateau of Shaanxi Province to make clear the effect of straw mulching on grain filling and yield of winter wheat from Sept.2007 to Jun.2008.The quantity of straw mulching had four levels of 9 000 kg/hm2 mulching（SM9）,6 000 kg/hm2 mulching（SM6）,3 000 kg/hm2 mulching（SM3）and non-mulching（CK）. The results indicated that in the slightly increasing stage,the grain filling rate of four treatments decreased gradually in the following order： CK,SM3,SM6 and SM9;However,in the fast and the slowly increasing stage,the grain filling rate of control was different with the slightly increasing stage.The grain filling rate can be arranged in the following order as SM3SM6CKSM9.The grain filling duration of SM9 was longer than contrast＇s 6d,SM6 and SM3＇s grain filling duration were almost the same as control＇s.During the fast and the slowly increasing stage,the contribution rate of SM9,SM6 and SM3 were all larger than control＇s,while in contrary for the slightly increasing stage.Compared with control,the amounts of 3 000 kg/hm2 could increase winter wheat yields after one year coverage.The SM3 treatment increased significantly 5.9% than control＇s.According to the research,SM3＇s production increase was mainly due to the grain filling rate was higher than control＇s in the fast and the slowly increasing stage.