Cenetic variability and breeding value of castor genotypes

Abstract

Six populations consisting of the parents (P1 and P2 ), F1 s, F2 s and backcrosses (BCP1 and BCP2) from three crosses of castor (Ricinus communis L.) were studied using randomised complete block design to determine the level of variabilities with a view to ascertaining the improvement potentials through selection. The results show that castor plants are largely heterozygous, an attribute that is highly desirable in plant breeding as they provide heterogeneous populations for a wider spectrum of selection. Genotypic differences were highly significant showing a wide range of variations in many of the characters studied. Phenotypic variations in many of the characters were largely non-genetic and broad sense heritability estimates were relatively low for some of the traits. There were strong indications that improvement of quantitative characters in castor may not be achieved by direct selection from the existing genotypes.