Solid culture of phosphate-solubilizing fungus, Penicillium sp. PS-113

摘要

A fungus, Penicillium sp. PS-113, isolated from soil showed the high phosphate-solubilizing activity in potato dextrose broth-rock phosphate to produce free phosphates to the culture broth with the concentrations of 585 ppm against rock phosphate. In this medium, the optimum temperature and initial pH to solubilize rock phosphate were 30 deg C and pH 7.5, respectively. In order to make the mass production of the conidia from this fungus, we cultured it on various solid-based media like barley, corn, wheat, rice, rice bran, and compost. As a result, the fungus highly produced conidia ranging from 2.1 to 5.1 x 10~9 conidia/g centre dot media on these solid media except compost-based medium, which was 10 times less than others. Effects of inoculation of the phosphate-solubilizing fungus as a biofertilizer were studied in perlite-based pot cropped with Zea mays Suwon 19. Inoculation of Penicillium sp. PS-113 increased in plant height (1.4 times), plant weight (5.2approx8.1 times) and root length (1.1approx1.2 times) at 60-day cultivation, compared to Hogland solution either without NH_4H_2PO_4 or displaced NH_4H_2PO_4 to powdered rock phosphate, a phosphorus source for plant growth.