Study on utilization of arbuscular mycorrhizal fungi in kidney bean cultivation - Effects of available phosphorus content on the infection of arbuscular mycorrhizal fungi and two species of arbuscular mycorrhizal fungi on the growth of kidney bean (Phaseolus vulgaris L.)

The effects of available phosphorus (P) content of Andosol on the infection of two species of arbuscular mycorrhizal fungi and the growth of kidney bean (Phaseolus vulgaris L.) were studied. The infection of arbuscular mycorrhizal fungi was suppressed when soil-available P (Bray No. 2) at planting time was 2.5 mg 100 g(-1). At 4.1 mg 100 g(-1) soil-available P, the growth of kidney bean cv. Dozyo and Celina was in no way affected by the inoculation of arbuscular mycorrhizal fungi. At a soil-available P level of 1.0 mg 100 g(-1), the inoculation of arbuscular mycorrhizal fungi increased the grain weight of kidney bean, and further increased with increasing spore number. Among inoculants, Glomus sp. (y) had a higher infection rate than Gigaspora margarita. Moreover, the growth of kidney bean was also higher with a higher infection rate, indicating that Glomus sp. (y) is a more suitable inoculant for kidney bean cultivation.