EFFECT OF MYCORRHIZAL INFECTION ON GROWTH AND NITROGEN UPTAKE OF SEVERAL GREEN MANURE CROPS GROWN UNDER EXCESS FERTILIZATION

由于AM真菌与捕获作物相关，在吸收土壤中积累的过量氮、磷等养分方面发挥重要作用，因此研究了过量施肥条件下AM真菌与Crotalaria、Sesbania、Sorghum、Avena等作物的相互作用。菌根接种总球囊菌（Glomus aggregatum）显著促进了这些作物的生长和养分吸收，特别是在高氮水平下生长的芥菜（Crotalaria juncea）。在花生作物上接种聚乙二醇也能观察到积极的效果。不同AM菌株间接种菌根的促进效果存在差异。为了评价作为绿色肥料的捕获作物对后续作物生长和氮吸收的潜力，研究了野田菁（Crotalaria spectabilis）、野田菁（Sesbania rostrata）和野豌豆（Vicia villosa）。这些作物的掺入对下列作物如嫩绿芥菜和高粱的生长和氮吸收有促进作用。AM孢子的体外培养繁殖技术目前正在进行中。

Since AM fungi associated with catch crops could play an important role to absorb the excessive nutrients such as nitrogen and phosphorus accumulated in the soil, interactions between AM fungi and the crops including Crotalaria, Sesbania, Sorghum, and Avena were investigated under excess fertilization. Mycorrhizal inoculation with Glomus aggregatum drastically promoted the growth and nutrient uptake of those crops, especially in Crotalaria juncea grown under higher nitrogen level. The positive effect was also observed in peanut crop inoculated with Gl. aggregatum. There was a difference in promoting effect of mycorrhizal inoculation among the tested AM strains. To evaluate the potential of catch crops incorporated as green manures on growth and N uptake of the following crop, Crotalaria spectabilis, Sesbania rostrata, and Vicia villosa were investigated. The increases in growth and nitrogen uptake of the following crop such as tendergreen mustard plant and sorghum by incorporation of these crops were confirmed. Propagation techniques of AM spores using in vitro cultures are now in progress.