Production of soybean mutants with pale-green-leaf phenotype by ion beam irradiation

Arase, Sachiko*; Abe, Jun*; Nozawa, Shigeki; Hase, Yoshihiro; Narumi, Issei; Kanazawa, Akira*

Soybean is an important crop in terms of production of food, oil and forage. We examined whether ion beam irradiation is effective in producing a mutant in soybean. By exposing dried seeds to 320 MeV carbon ions, we could detect plants with a visiable altered phenotype. The observed change was a chlorophyll deficiency, as evidenced by pale-green leaves. Frequency of this type of change was 0.1% and 0.19% for M plants irradiated at 2.5 Gy and 5 Gy, respectively. The M progeny of four out of six M plants maintained the altered phenotype. Thus, at least these four M had stable heritable change that caused the altered phenotype, demonstrating that ion-beam irradiation at 2.5-5 Gy can induce mutations.