施磷对旱地小麦土壤水分、干物质累积和转运的影响

Effects of Phosphorus Fertilizer on Soil Moisture,Dry Matter Accumulation and Translocation of Dryland Wheat

为探明旱地小麦最佳施磷量和施磷方式，在山西省闻喜县进行了施磷量（P2O5）为75、112．5、150kg·hm2和施磷土层深度为20、40cm的田间试验，分析了不同处理对旱地麦田土壤水分、干物质累积与转运的影响。结果表明，随着施磷量的增加，小麦花前0～100cm土层的土壤水分含量提高，且40cm土层施磷较20cm土层施磷效果显著；小麦各生育时期单株干物质量增加，且40cm土层施磷条件下差异显著。施磷150kg·hm2时，40cm土层施磷较20cm土层施磷，小麦花前叶片和茎秆＋茎鞘的干物质量增加，成熟期茎秆＋茎鞘干物质量显著降低，籽粒干物质量及其所占比例增加。随施磷量的增加，小麦花后干物质累积量及其对籽粒的贡献率均显著增加，且40cm土层施磷较20cm土层施磷效果显著。施磷条件下，花后干物质累积量与小麦越冬一孕穗期土壤水分含量关系密切，与孕穗期土壤水分含量尤为密切。40cm土层施磷150kg·hm2有利于提高旱地麦田孕穗期前0～100cm土层土壤水分含量，促进小麦茎秆＋茎鞘中的干物质向籽粒转运和花后干物质累积及其对籽粒的贡献率，从而提高籽粒产量。

In order to find out the best amount and application way of phosphorus fertilizer for dryland wheat,a field test was carried out in Wenxi,Shanxi province. Two application depths （20,40 cm） and three phosphorus amounts （P20s 75,112.5,150 kg . hm-2） were conducted. The effects of phosphate fertilizer on soil moisture and dry matter accumulation and translocation of dryland wheat were ana- lyzed. The results showed that increasing the amount of phosphorus improved 100 cm soil moisture of dryland wheat before anthesis,and the effect of 40 cm depth application was more significant than that of 20 cm depth. With the increase of the amount of phosphorus,the weight of plant dry matter were increased at different growth stages and significantly different under the condition of 40 cm depth. Comparing with 20 cm depth, under high phosphorus with 40 cm depth, dry weight of leaf, stem and sheath before anthesis was increased. However,the dry weight of stem and sheath was decreased significantly at maturity stage, and the dry weight of grain and its ratio to plant were increased at this stage. With the increase of the amount of phosphorus, contribution rate of dry matter accumulation a-mount to grain after anthesis was improved significantly and the effect of 40 cm depth was more obvious than that of 20 cm depth. In addition,for dryland wheat under the different depths of phosphorus application,the relationship between soil moisture from wintering to booting stage and dry matter ac- cumulation amount after anthesis was closely,especially for soil moisture of booting stage. In conclu- sion,40 cm depth application of 150 kg ~hm-2 phosphorus fertilizer for dryland wheat is beneficial to improve the soil moisture in 100 cm until booting stage. It is benefit to promote the transloeation of dry matter from stem and sheath to grains, and improve the accumulation of dry matter and its contribution to grain after anthesis,which finally improved grain yield.