Inheritance of Unilateral Incompatibility in the Genus Capsicum

Unilateral incompatibility is reported to occur between the species of Capsicum pubescens complex (Capsicum cardenasii Capsicum. eximium and Capsicum pubescens) and other species of genus Capsicum when the latter are used as the male parent. The relationship between self-incompatibility and unilateral incompatibility are yet to be resolved even in the most intensively investigated crosses within and between species of Lycopersicon and Solanum. Unilateral incompatibility in Capsicum has been less intensively studied compared to some other genus in family Solanaceae. This study was, therefore, conducted to help us to understand the genetic control of unilateral incompatibility in Capsicum. Experiment results showed that while the pistil behaviour of F1 hybrids agrees with the pistil behaviour of F1 hybrids from unilaterally incompatible crosses in other genera of Solanaceae, the pollen behaviour does not agree with data obtained from other genera of Solanaceae. No segregation ratio was obtained for unilateral incompatibility in the backcross progenies, this result does not agree with data from other genera in the Solanaceae either. Possible reasons for not obtaining segregation for unilateral incompatibility may be the small size of backcross progenies and%252For distorted segregation ratios. As a conclusion it seemed more probable that, in Capsicum, unilateral incompatibility has arisen as a by-product of genetic divergence between the C. pubescens complex and the other chile peppers, not as a product of natural selection