Genetic control of gynoecy in the buffalo gourd

Abstract

The buffalo gourd, Cucurbits foetidissima HBK., is currently under Investigation as a possible domesticate. This xerophytic species is sexually dimorphic, developing both monoecious and gynoecious sex types. Male floral buds on gynoecious plants are antherless and abort in early phases of development. High yield potential associated with gynoecy and the breeding implications of sexual dimorphism indicate the future importance of this trait. Progeny from gynoecious X monoecious crosses, monoecious X monoecious crosses, and monoecious self-pollinations were studied to elucidate the mechanism of genetic control of sex expression. A high percentage of plants remained vegetative during their first growth season making statistical treatment of the data difficult. However, observations on the data support a control scheme involving at least one major locus as follows: monoecy results from the homozygous recessive state (m m), whereas gynoecious plants are obligately heterozygous (M m).