摘要： 为明确稻茬麦合理的氮素施用及秸秆养分归还特征，以宁麦9号和豫麦34为材料，研究了不同氮肥基追比例（1：9，3：7，5：5，7：3，施氮量225 kg/hm²）对小麦群体干物质、氮、磷和钾积累垂直分布的影响。结果表明，小麦籽粒产量以基追比5：5处理最高。植株干物质和养分积累存在明显的层次分布，适当提高追肥比例显著提高了植株各层干物质、氮、磷和钾素的积累量。不同施氮处理叶片干物质、氮、磷主要积累于中上层，钾积累于下层；茎鞘干物质和钾主要积累在下层，氮、磷积累在中上层。各叶层、茎鞘层干物质、氮、磷、钾积累量与籽粒产量均呈显著或极显著正相关。残茬秸秆（倒4层叶+倒4层茎+颖壳和穗轴）干物质、氮、磷、钾还田量占秸秆总量的比例分别约为50%，40%，50%，40%。

关键词: 氮肥运筹, 稻茬小麦, 氮磷钾, 垂直分布

Abstract: It is very important to elucidate the nutrient status of wheat canopy to better utilize nitrogen fertilizer and nutrient of wheat straw.Field experiments with five treatments(Basal-topdressing ratios were 1:9,3:7,5:5,7:3 at 255 kg/ha and N0) by using two cultivars(Ningmai 9 & Yumai 34) were conducted in Nanjing during 2010 and 2011.The experiment was sampled at maturity stage.The results showed that grain yield reached the highest at the treatment of N5/5.The dry matter,N,P and K accumulation amount in the straw increased with the increasing of topdressing ratio appropriately.There were significant vertical differences of dry matter,nitrogen,phosphorus and potassium accumulation in the wheat canopy layers.Dry matter mainly accumulated in the middle and upper leaf layer and lower sheath layer,N and P mainly accumulated in the middle and upper leaf and sheath layer,K mainly accumulated in the lower leaf and sheath layer.There were significant linear relationships between dry matter,nitrogen,phosphorus and potassium accumulation and grain yield in different leaf and sheath layers.When the straw stubble(Glume+the leaf and stem-sheath in the fourth layer) was returned to the field only,the proportions of dry matter,N,P and K were 50%,40%,50% and 40% respectively.

Key words: Nitrogen application, Wheat following rice, Nitrogen,phosphorus and potassium, Vertical distribution

中图分类号: 

• S512.1

• S143.2