Endosperm abnormalities in Triticum–Secale combinations. II. Addition and substitution lines

Abstract

The relationships between kernel shrivelling and endosperm, embryo, and antipodal development were investigated in wheat–rye addition and substitution lines.A positive relationship was established between mature kernel shrivelling and the number of aberrant endosperm nuclei during the first 10–15 divisions after fertilization. The presence of aberrant nuclei was associated with specific rye chromosomes; chromosomes 5R, 4R, 6R, 3R, and 1R, in descending order of importance, are responsible for aberrant nuclei induction. The short arm of 4R was without effect and a major effect was noted for the long arm of 6R. Thus, the main effect of chromosomes 4R and 6R was not associated with the short arm.No relationship could be established between kernel shrivelling (or number of aberrant endosperm nuclei) and (1) amount of heterochromatin, as revealed by Giesma staining, or (2) rate of antipodal degeneration. A tentative negative relationship was found between early starch deposition in the endosperm and kernel shrivelling.