Studies of the intraspecific competition and performance of chance‐hybrids inLotium multiflorumLam.1

摘要

AbstractIn order to study the effects of competition on the genotypic composition of chance‐hybrids inLoliuni multiflorum, eight chance‐hybrids were produced according to Burton (1948). Inbred lines and cultivars were used as parents. The proportions of parental and hybrid components in the seeds and growing‐field stands of the chance‐hybrids were determined over three cuts using gel electrophoresis. The realized hybrid proportions in the seeds, at a maximum of 38.3, were considerably lower than the theoretically expected 50. In the field stands, the hybrid proportions of the chance‐hybrids derived from inbred lines increased considerably and continously over cuts, whereas those of the chance‐hybrids produced from cultivars increased only slightly. A maximum hybrid tiller proportion of 76.8 was found at the third cut. Correspondingly, the total yield of the chance‐hybrids produced from cultivars was only slightly higher than that of the parents. The production of chance‐hybrids, therefore, proved to be sensible only if inbred lines had been