播量对麦后复种油菜生物产量及耕层土壤养分的影响

摘要

为明确西北地区播量对麦后复种油菜地耕层土壤养分变化的影响,在甘肃省古浪县进行小区试验,研究不同播量(7.5、11.25、15.0、18.75和22.5 kg/hm2)对油菜生物产量和耕层土壤养分的影响,提出适宜的播种量.结果表明:油菜生物产量随着播种量的增加先增加后降低,在播种量15.0 kg/hm2时达最大;麦后复种油菜可提高土壤有机质质量分数,增强土壤速效磷的解吸,根系分泌的有机酸类物质可降低土壤pH;麦后复种油菜显著降低土壤速效钾质量分数,应注意补施钾肥.%In order to clarify effect of seeding rate on soil nutrient change of soil nutrient under wheat stubble multiple cropping rape in northwest region,a plot expriment was conducted to examine effects of yield and soil environment of pH,organic matter,available N,available P,available K in Gulang country.Six treatments(CK,T1,T2,T3,T4,T5) were designed with seeding rate of 7.5 kg/hm2,11.25 kg/hm2,15.0 kg/hm2,18.75 kg/hm2 and 22.5 kg/hm2.The results showed that the yield of rape was highest at 15.0 kg/hm2.The rape yield increased with increase of seeding rate.Wheat stubble multiple cropping rape could improve the content of soil organic matter,increase soil available P desorption,root secretion of organic acids material could reduce the soil pH;wheat stubble multiple cropping rape significantly reduced the soil available potassium mass fraction,we should pay attention to complement potassium application.