Classical genetics, cytogenetics, and traditional breeding in castor bean

Abstract

Castor being a perennial, cross pollinated, sexually polymorphic crop with high environmental sensitivity, initial plant breding efforts were restricted to plant height and duration. Domestication of a wild, perennial crop to an annual crop of medium plant height and duration is the first success. Further, development of a two-line breeding system and standard seed production technology led to successful commercial exploitation of heterosis. Being a monotypic genus, diversification of parental base is restricted to intra-generic. intra specific or inter-varietal hybridization. Phenotypic expression is highly plastic and varies with locations and seasons. Majority of the morphological characters are monogenic, independently assorted with very limited linkages among the traits. However, informtion on genetics of major morphological characters is scattered in several old publications.