Genotype of Functionally Hermaphroditic Grape Clones

Abstract

The way in which the grape flower is able to function in reproduction is closely associated with floral morphology, and is of considerable importance to the grape industry as well as to the grape breeder and geneticist. Oberle ^† , in an extensive study of grape breeding data at the Geneva Station, has determined the genetic basis for the inheritance of floral morphology and function in grapes. He recognized three distinct flower types, only one of which normally appears on any one individual vine. These, classified as to their reproductive function, are (1) hermaphroditic (a flower possessing both a normally developed pistil and erect stamens with normal anthers), (2) pistillate (a flower possessing a normally developed pistil but with reflexed or down-curved stamens having anthers which produce non-viable pollen-male sterile), and (3) staminate (a flower possessing an incompletely developed pistil-female sterile but with erect stamens and normal anthers). Crosses between these types gives progenies in which the parental types are recovered in simple Mendelian ratios.