宿主植物的栽培密度对AM真菌孢子产量的影响

对宿主植物的栽培密度与孢子产量的相关性进行了试验研究.以百喜草Paspalum notatum为宿主,每盆栽1、5或10株,以稍长无梗囊霉Acaulospora longula为供试菌株.植株生长4个月,结果发现1株/盆的侵染率显著高于其他2个栽培密度,但是三者的泡囊和丛枝的百分率没有差异.3种栽培密度下每盆植株的地上部生物量没有差异,但根系生物量随着栽培密度的增加而降低,土壤中的孢子密度也具有同样的趋势.相关分析发现,孢子密度与根系生物量密切相关.试验结果表明,宿主植物的高密度栽培可能导致分配到根系碳水化合物减少,从而减少AM真菌的孢子产量.

Influence of Host Planting Density on Sporulation of Arbuscular Mycorrhizal Fungi

The relationship between host planting density and sporulation of arbuscular mycorrhizal(AM) fungi was investigated.Acaulospora longula were inoculated into bahia grass pots with 1,5 or 10 plants.After 4 months growth,the AM colonization were much higher in pots with 1 plant than that in pots with 5 or 10 plants,but no difference in the vesicle percentage and arbuscle percentage was observed.Although the shoot biomass didn't vary between 3 planting densities,the root biomass and spore density decreased with the increasing of planting density.Correlation analysis revealed a close relationship between root biomass and spore density.The result suggests that high planting density probably reduces the carbohydrate partitioned to the roots,and further retards the sporulation.