Heterosis in vegetable crops

Abstract

This chapter uses heterosis to mean hybrid vigor relative to the better parent, or where inbreeding depression is severe, to the comparable open pollinated cultivars. Although there is heterosis expressed for yield traits in many of the vegetable crops, a primary advantage of hybrid cultivars is the protection they provide for proprietary lines developed by plant breeders. Self-pollinated crops that produce few seeds per cross make it difficult to produce hybrids economically. Vegetable crops such as legumes and lettuce are important in the USA. Many crops in the Solanaceae are self pollinated and are adaptable to hybrid production. Eggplant, pepper, and tomato are examples of successful use of hybrids. Most hybrids are produced by hand emasculation and hand pollination; however, it may be possible to produce seeds less expensively using male sterility or exserted stigma genes to increase the number of seeds and reduce the time required per cross.