Components of genetic variance for some quantitative characteristics in castor bean

Abstract

The castor bean (Ricinus communis L.) cultivation emerges as a promising activity for biodiesel production. There is limited information on genetics of modern castor bean cultivars. To be able to foresee results of selection for a characteristic in a population, it is necessary to determine the values of genetic variance, environmental variance and their interaction within the total phenotypic variance. Castor bean studies have mostly been concentrated on the roles of additive and dominant gene effects in the expression of quantitative characteristics. Two two-line castor bean hybrids have been evaluated for mode of inheritance and gene action in the expression, especially epistatic one, of the number of flowers, number of filled seeds per flower head and 1000-seed mass. Epistatic gene effects have played important roles in the inheritance of the studied characteristics in both hybrids. Highly significant values of epistatic gene effects additive × additive and dominant × dominant have been found for all three characteristics in both crosses. Highly significant epistatic gene effect additive × dominant has been found for the number of filled seeds per flower head in cross L2 × L3.