Gamma 線 照射가 煙草의 種子發芽 및 葯培養에 미치는 影響

Effect of gamma radiation on seed germination and androgenesis in nicotiana tabacum L.

The seeds of tobacco cultivar ‘NC 82’ were irradiated with 5, 10, 20, 40 KR and anthers of the cultivar were irradiated with 0.5, 1.0, 1.5 KR of γ-ray. The seed germination in petri-dish was not effected by the treatment of the irradiation up to 40 KR. However, the extention of seed storage period decreased the germination and seedling growth. The androgenesis of tobacco derived from 10 KR γ-ray irradiated seeds was enhanced, but reduced at the level of 20 KR. The androgenesis were studied in 2 levels, i.e. androgenic anthers and androgenic plants per anther. The number of androgenic anthers were increased by 10 KR and reduced by 20 KR of γ-ray irradiation. The number of androgenic plants per androgenic anther did not show any specific trand. The effect of γ-ray irradiation on the anther was greater than on seed. At low dose of y-ray, 0.5 KR, the numbers of androgenic anthers were greater than those of control. But at 1.5 KR level, no androgenic anthers were observed. Three different irradiation methods on anthers were compared. The greatest number of contamination by fungi and bacteria was observed when anthers were transplanted from irradiated bottle to bottle contained fresh medium after irradiation (Method Ⅱ). In the case of irradiation on inoculated anthers in flask (Method Ⅰ), the toxicity of sugars by radiolysis was not observed. In order to eliminate the effect of irradiated medium and contamination after transplanting, irradiation on the flower bud before inoculation in flask (Method Ⅲ) was more desirable than the other 2 methods.