植物育種法に関する理論的研究 : I.自殖性植物の雑種後代における遺伝力の変化

抄録

Conc, erning cconomically important quantitative characters of autogamous cereals, the heritability in the F₂ generation is generally so low that we can hardly select individuals with surperior genotypes among the segregating plants of the hybrid population. It is expected, however, that on account of, decreasing heterozygosity by self-fertilization, the heritability gradually increases with the repetition, of generations, because Lhe non addrtrve actlon of genes will decrease owing to the loss of heterozygosity. In addition, it is expected that tlne low heritability of such economic char(acters as are highly influenced by the environmental variation will be raised by taking mean values of plant progenies into account. This paper deals with the results of comput.ations of heritabilify values in hybrid bulks and in plant progenies in several successive h ybrid generations. It also includes some discussions on the effective method of breeding superior genotypes for economic haracters.