Inheritance of Seed Weight in Ricinus communis L.

Abstract

THE cross investigated was Brazilian large seeded, L (mean seed weight 913 mg), by Peruvian small seeded, S (mean seed weight 147 mg). The method followed was that of continuous back-crossing of heterozygotes to one of the parent varieties, S, with the object of isolating bimodal curves indicating monohybrid segregation. Once this was achieved the new homozygous genotypes could be combined in various ways to elucidate the genetical architecture of a typical quantitative character. Since the mode of inheritance proved to follow a geometric rather than an arithmetic pattern, it is convenient to express the results in terms of log seed weight.