Genetic parameter estimates and cluster distribution among local and exotic Castor collections in Nigeria

Abstract

on genetic variability and relatedness were conducted on 86 castor accessions at three locations in Niger state, Nigeria. The study was aimed at providing intormation for commencement of a castor improvement programme in the study area. The castor accessions were evaluated using Alpha Lattice Design with three replications. Ten agro-morphological data including establishment counts (%), days to first spike flowering days to first spike maturity, branches per plant, spike/plant, plant height at maturity, seed yield (kg/ha), and seed physical properties were taken. The results revealed significant variation among the accessions for all the traits evaluated. The collections revealed high divergence in seed colour, seed shape, seed mottle, seed caruncle and seed sizes. Phenotypic coefficients of variation were high for all the studied traits except for days to maturity (5.33%). High phenotypic and high genotypic coefficients of variation were observed for 100 seed weight (71.87% and 52.43%), branches per plant (41.45% and 22.73%) and spike length (54.74% and 43.17%6) respectively, indicating high variabilityfor these traits among the accessions. The k-mean cluster analysis revealed high divergence, and random cluster distribution of the accessions irrespective of the sources/collection points. This study provides information on possible parental combinations to generate useful recombinants. The high yielding groups (cluster 2 and 5) contain potential parents that could be used for development of useful segregating populations for increased seed yield. The information provided in the study could be useful for castor breeding programme in Nigeria.