Isolation of gibberellins-producing fungi from the root of several Sesamum indicum plants

Gibberellins (GAs) play important roles in plant growth and development. Fifty-four fungi were isolated from the roots of 4 kinds of Sesamum indicum plants, and the production of GAs was spectrophotometrically examined. The number of GA-producing fungi was two strains from S. indicum, four strains from Gold S. indicum, and five strains from Brown S. indicum. Eleven fungi with GAs-producing activity were incubated for seven days in 40 ml of Czapek's liquid medium at 25°C and 120 rpm, and the amount of each GA in the medium was measured by gas chromatographymass spectrometery (GC-MS). Penicillium commune KNU5379 produced more GA₃, GA₄, and GA₇ than Gibberella fujikuroi, Fusarium proliferatum, and Neurospora crassa which are known as GAs-producing fungi. GAs-producing activity of the P. commune KNU5379 was shown to produce 71.69 ng of GA₁, 252.42 ng of GA₃, 612.00 ng of GA₄, 259.00 ng of GA₇, and 202.69 ng of GA₉ in 25 ml of liquid medium. Bioassay of culture fluid of GA-producing fungi was also performed on rice sprout.