灌溉频率和施氮量对滴灌春小麦干物质积累及产量的影响

通过大田试验,研究了不同灌溉频率和施氮量下,滴灌春小麦干物质积累、分配和产量的形成规律。结果发现,相同施氮量下,随着灌溉频率的增加,小麦的LAI、干物质累积最大速率和花后干物质贡献率均表现为中频灌溉(M)高频灌溉(H)低频灌溉(L);相同灌溉频率不同施氮量下,小麦的LAI、干物质累积速率和花后干物质贡献率则均表现为N2N3N1N0;MN2处理与HN2和LN2处理相比,小麦的LAI提高了11.3%和22.1%,干物质累积最大速率提高了2.3%和1.3%,花后干物质贡献率增加了1.71%和2.28%;小麦的库容量提高了12.3%和13.7%,差异均显著(P0.05)。产量构成的通径分析表明,小麦产量指标中,对滴灌春小麦产量的贡献依次为穗粒数穗数千粒重。灌溉频率和施氮量对小麦产量的互作效应明显,当施氮量为308.63kg·hm-2、灌溉频率约为6.52d一次时,滴灌春小麦产量达到最大值(8 804.2kg·hm-2)。

Effect of Irrigation Frequency and Nitrogen Application rate on Dry Matter Accumulation and Yield of Drip irrigated SpringWheat

Through the split plot experiment,it was investigated that the effect of different irrigation frequency and nitrogen application rate on the maximal rate of dry matter accumulation,distribution and yield components of spring wheat with drip irrigated. The result indicated that LAI,the maximal rate of dry matter accumulation and dry matter contribution proportion after anthesis of spring wheat showed M>H>L with the same nitrogen application rate and increasing irrigation frequency.Under the same irrigation frequency and different nitrogen application rate,the order of those indexes showed N2>N3>N1>N0.Compared with the HN2 and LN2 treatments,the LAI of MN2 treatment was increased by 11.3%,22.1%,the maximal rate of dry matter accumulation was increased by 2.3% and 1.3%, and the dry matter contribution proportion after anthesis of spring wheat was increased by 1.71% and 2.28%.The sink capacity of spring wheat in the MN2 treatment was increased 13.7% and 12.3% than that of the LN2 and HN2 treatments,respectively,the deference was significant. The path analysis result showed that the effect of yield indexes to yield of drip irrigated spring wheat were grains per spike>spike number>1 000 grain weight. There was significant interactive effect between irrigation frequency and nitrogen application rate on wheat yield,and drip irrigated spring wheat got the highest yield(8 804.2 kg·hm^-2) when the nitrogen rate was 308.63 kg·hm^-2 and the irrigation frequency was 6.52 d. Consequently,through suitable irrigation frequency and nitrogen application, spring wheat can keeping structure community,promote the dry matter producing and high efficiency distributing and increase the yield of spring wheat.