Adaptability evaluation of castor bean (Ricinus communis L.) genotypes at wondogenet, Ethiopia
Abstract
Castor (Ricinus communis L.) locally known as ‘Gulo’ is a species of flowering plants in the spurge family (Euphorbiaceae) which contains a vast number of plants mostly native to the tropics. Castor belongs to a monotypic genus Ricinus and sub-tribe Ricininae. It was initially believed to have four centers of origin: East Africa (Ethiopia), Northwest and South West Asia and Arabian Peninsula, India, and China. However, Ethiopia is considered to be the most probable site of origin because of the presence of high diversity. The overall objective of this research was conducted to test environmental adaptability of castor bean genotypes at wondogenet, Ethiopia. The experiment was conducted at Wondogenet Agricultural Research Center’s (WGARC) on-station testing site during the main cropping season of 2022. Highly significant (P<0.01) differences among varieties were observed in the testing site for days to plant height, number of capsules per plant, number of nods per plant, nod length, number of branches per plant and seed yield per hectare. Caster seed yield for genotypes tested at the tested area ranged from 1114 to 1451.27 kg/ha, and the mean value was 1235.95 kg/ha. The top yielders included Acc#95, Acc#82, and Hiruy, with 1451.27, 1294.03, and 1260.27 kg/ha, respectively. Compared with environmental variance, genetic variance was larger for plant height, number of racem per plants, length of main racem, number of capsuls per plant, number of nodes per plants, node length and number of branches per plants. Therefore, the higher proportion of phenotypic variance observed on these traits was due to the larger proportion of genotypic variance.