Dynamics of Community Structures of Arbuscular Mycorrhizal Fungi in the Different Winter Cropping Managements.

Arbuscular mycorrhizal (AM) fungi are obligate symbiotic microorganisms and would help the uptake of such an immobile mineral nutrients as phosphate. In general, since there is host compatibility between AM fungi and crop plants, the difference of crops affects the AM fungal community in the crop roots and soil. However, there is little information regarding the dynamics of AM fungal community under different winter cropping managements in Japan. The objectives is to elacidate the dynamics of AM fungal community under different winter cropping managements. In the present study, four plots including 4W (sowing wheat in April), 11W (wheat as winter crops), 11C (canola) and F plots (fallow in winter duration) were established. Soybean as summer crops was grown from May to November before winter cropping managements. The AM fungal community in the crop roots and soils after cultivation of winter crops were analyzed by construction of PCR amplified the LSU rDNA clone library. In total, nineteen groups including ten of Glomus, two of Gigaspora, three of Scutellospora, two of Acaulospora, one of Diversispora and one of Unknown were found in the crops roots and soils. AM fungal groups of each crops roots of 4W, 11W and 11C were 8.33, 6.33 and 2.00, respectively. AM fungal groups in soils of 4W, 11W, 11C and F plots were 4.67, 5.33, 4.00 and 3.33, respectively. Especially, the AM fungal community of the soil at the 11C and F plots  were  simply than 4W and 11W plots. Thus, it will be expecited that the introduction of non-mycorrhizal plants or fallow during in winter duration was simplified the AM fungal community.