Variability in seed quality traits in castor germplasm

Abstract

Castor is an industrial oilseed crop with great potential for biorefineries. However, little is known about the variability in the bioactive compounds in castor germplasm. This study evaluated seed weight, oil content, fatty acid profile, tocopherols, and phytosterols in 160 accessions of the USDA-ARS castor germplasm collection. The accessions were grown in Cordoba, Spain, under three different environmental conditions. Environmental and genotype-by-environment interaction effects were predominant for most traits, resulting in moderate to low broad-sense heritabilities, which ranged from 0.12 for total tocopherol content to 0.88 for hundred-seed weight. The genetic variability in the seed quality traits identified in the collection was lower than that reported previously for the germplasm of wild and semi-wild accessions from Spain, which is attributed to the lower genetic diversity in cultivated than in wild forms. The variation in seed quality traits in castor germplasm can be exploited to improve the concentration of bioactive compounds in castor cultivars.