黃色種 煙草 細菌性마름病의 抵抗性 遺傳

Inheritance of resistance to bacterial wilt in flue-cured tobacco(nicotiana tabacum L.)

Six cultivars of flue-cured tobacco including BY 4 were evaluated for resistance to bacterial wilt caused by Pseudomonas solanacearum E.F. Smith in the greenhouse by artificial inoculation and in an infested field. Two crosses, BY 4 x NC 82 and BY 4 x BY 104, were made. To study the mode of inheritance of the resistance to bacterial wilt, parents, F₁÷F2÷B₁ and B₂ populations from two crosses were investigated for their variance of disease index, degree of dominance, heterosis, inbreeding depression, gene effect, heritability and minimum number of effective genes in an infested field. A high positive correlation was observed between disease readings taken in the greenhouse and in the field. Resistance to bacterial wilt was inherited quantitatively and was presumed to be controlled by many genes. A partial dominance of susceptibility was observed. Additive gene action does a major role in inheritance of resistance to bacterial wilt and epistatic effect was also appeared to be involved. Heritability of resistance to bacterial wilt was relatively low in early generations.