Phenotypic improvement of USDA 110 into a high temperature tolerant strain in terms of ion-beam microbial mutation-breeding technology

イオンビーム微生物突然変異育種技術によるダイズ根粒菌USDA 110株の高温耐性への形質改良

武田 喜代子*; 手島 光平; 佐藤 勝也; 鳴海 一成; 横山 正*

Takeda, Kiyoko*; Tejima, Kohei; Sato, Katsuya; Narumi, Issei; Yokoyama, Tadashi*

Major constraint of biofertilizer utilization in agricultural practice is a serious deterioration of qualities in biofertilizers under both storage and transportation conditions. In order to prevent deterioration in variability of inoculants in biofertilizers exposed to high temperature, we are trying to improve a phenotypic character concerning high temperature tolerant in USDA 110, which is a worldwide superior inoculant to soybean. In this study, ion-beam microbial mutation-breeding technology is used to generate high temperature tolerant mutants. We obtained high temperature tolerant mutants of USDA 110, which can survive at 45C for 5 days. Now, we are characterizing these mutants in terms of differences in several phenotypic properties.