不同施氮水平下AMF群落对白三叶草生长及养分吸收的影响

Effects of AMF community on the growth and nutrient uptake of white clover at different N supply levels

以封丘土壤为培养基质,研究在不同N水平下接种分离自封丘长期定位施肥土壤的丛枝菌根真菌(AMF)群落对白三叶草生长的影响。结果表明:在一定N水平下,AMF侵染率随着外界施N水平升高而降低。3种N水平下,分离自NK(N、K混施)土壤的AMF群落能促进白三叶草生长及营养吸收;高N水平下,分离自1/2OM+1/2NPK(一半有机质一半化肥)土壤的AMF群落对白三叶草营养无贡献,反而会抑制其生长。不同N水平下AMF群落对白三叶草的营养贡献出现差异,这与长期不同的培肥方式下AMF的群落结构发生变化有关。

The effects of arbuscular mycorrhizal fungi（AMF） community,which was collected from a long-term fertilization field in Fengqiu,Henan Province,on the growth of white clover （Trifolium repens） at different N levels were studied using Fengqiu soil as substrate.The results showed that root colonization decreased with the increase of three N supply levels.The AMF community collected from NK soil （nitrogen and potassium chemical fertilizers） improved the growth and nutrient uptake of white clover at three N supply levels.However,at high N levels,the AMF community collected from 1/2 OM＋ 1/2 NPK soil（1/2 organic matters＋ 1/2 nitrogen,phosphorus,and potassium chemical fertilizers） had no help to nutrient uptake,but inhibited the growth of white clover.It suggests that different regimes of longterm fertilization change the structure of AMF community,and thus have different effects on the growth and nutrient uptake of white clover.