Chrysosporium pseudomerdarium Produces Gibberellins and Promotes Plant Growth

We isolated 10 endophytic fungi from the roots of drought stressed soybean cultivar Hwangkeumkong and bioassyed on waito-c rice and soybean seedlings, in order to identify plant growth-promoting fungi. The fungal isolate D-2-1 provided the best result for plant height and biomass promotion as compared to wild type Gibberella fujikuroi. The D-2-1 culture filtrate (CF) was analyzed for the presence of gibberellins (GAs) and it was observed that all physiologically active GAs, especially gibberellic acid, were present in higher amounts (GA(1), 0.24 ng/ml; GA(3), 8.99 ng/ml; GA(4), 2.58 ng/ml and GA(7), 1.39 ng/ml) in conjunction with physiologically inactive GA(5), GA(9), GA(15), GA(19), and GA(24). The fungal isolate D-2-1 was identified as a new strain of Chrysosporium pseudomerdarium through phylogenetic analysis of 18S rDNA sequence. Plant growth promotion and GAs production capacity of genus Chrysosporium have been reported for the first time in this study.