油菜是我国和世界主要油料作物，对氮磷肥需求量大，但是氮磷肥利用率低，会造成资源浪费和环境污染等问题。由于根际促生菌能够改善植物生长并提高养分吸收，近些年来不少生物肥料中添加有根际促生菌。采用土培试验，探究了两种根际促生菌(巨大芽孢杆菌和短小芽孢杆菌)在不同氮磷条件下对油菜生长和养分吸收的影响，以期为油菜肥料研制和施肥技术提供帮助。结果表明：油菜在缺氮或缺磷条件下的地上部干重仅为正常氮磷供应的20%；巨大芽孢杆菌在正常氮磷供应条件下改善了油菜生长，促进了油菜对P、K、Zn和B 4种营养元素的吸收，而在缺氮和缺磷条件下没有效果；短小芽孢杆菌在缺氮、缺磷和正常氮磷条件下均没有效果。因此，氮磷肥对油菜生长至关重要，巨大芽孢杆菌能够在适当氮磷供应的条件下发挥促生作用。

As one of main oil crops in China and even in the world, rape has a huge demand for nitrogen (N) and phosphorus (P) fertilizers, but its use efficiency of N and P is too low, which may result in resource waste and environmental pollution. Plant growth-promoting rhizobacteria (PGPR) has been added to many biological fertilizers in recent years because it can promote plant growth and improve nutrient uptake. The present study investigated the effects of two RGPRs ( Bacillus megaterium and Bacillus pumilus) on growth and nutrient uptake of rape under different N and P application levels by soil culture experiment in order to provide the theoretical foundation for the fertilizer development and fertilization technology for rape. The results showed that the dry weight of aboveground part of rape under N or P deficiency was only 20% of that under normal N and P application; B. megaterium promoted the growth of rape and improved the uptake of P, K, Zn and B under normal N and P application, but had no effects under N or P deficiency; B. pumilus had no effects under N or P deficiency and normal N and P application. Therefore, the application of N and P fertilizers is critical for the growth of rape, and B. megaterium has growth-promoting effects under proper N and P application.

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中国科学院战略性先导科技专项B 类(XDB15030000)和国家自然科学基金项目(41271257、41230855)资助。