玉米育苗接种VA菌根真菌的田间侵染力和接种效应

Infection potential and effects of VAM fungi on corn with seedling inoculation

用测定玉米田间VA菌根真菌侵染率和繁殖体数量动态及接种反应的方法 ,研究玉米营养袋接种VA菌根菌的田间侵染力和接种效应及其受不同施肥水平的影响。结果表明 :(1)在玉米整个生育期 ,特别是前期接种VA菌根菌提高了田间VA菌侵染率和繁殖体数量。 (2 )接种从同一土壤筛选的菌种在半量施肥和不施肥水平下提高了植株含磷量、籽粒含磷量和总吸磷量 ,并增加了玉米的籽粒产量和秸秆量 ;接种引进的G .caledonium菌种在不施肥水平下也有较好的菌根效应。 (3)各接种处理的VA菌田间侵染率均表现出 30d左右达到最高 ,然后逐渐下降。除Acauloporaspp .菌种外 ,接种其他几种VA菌的田间繁殖体数量在 30d达最大 ,以后保持稳定或略有减少。接种筛选的Acauloporaspp .菌种其繁殖体数量在 4 9d以后达到最大。 (4 )半量施肥和不施肥与全量施肥相比 ,VA菌有较高的田间侵染率 ,并在整个生育期保持较高的繁殖体数量。但生育期内田间VA菌繁殖体数量和其侵染率的关系难以确定 。

The development of infection and propagule numbers of VAM fungi and corn response in fields after transplanting with seedling inoculation were studied,the results showed:(1)VAM inoculation promoted the infection and propagule numbers of VAM fungi especially in the early stage of corn.(2)With half amount of (1/2F) or no(O)fertilizers,inoculation of Acaulopora spp.and Glomus spp.,which screened from the soil of the experimental site,improved the phosphorus concentration in corn tissues and seeds,and increased the yields of seeds and stalks;inoculation of imported G.caledonium was also effective on corn with no fertilizers;(3)VAM infection of corn had its peak about 30 days after inoculation and fell gradually afterwards.VAM propagule numbers of G caledonium and Glomus spp.got the highest 30 days after inoculation and maintained or slightly declined from then on;inoculation of screened Acauloprora spp.had the highest infection rate and its propagule number reached the highest 49 days after inoculation;(4) the VAM infection and propagule numbers were higher with half amount of (1/2F) or no (O) fertilizers than that with total fertilizers.But,as the infection potential can be expressed as dynamic development of infection and propagule numbers of VAM fungi in the whole growing season of corn,the relationship between VAM infection and propagule numbers was uncertain,so there must be many factors in function with formation and effectiveness of VAM in fields