Desirable cross combinations based on cluster analysis among okra (Abelmoschus esculentus Linn.) genotypes
Crop improvement in okra is a very important activity which is to be directed towards finding the most desirable parental combination for the purpose of improving certain desirable traits in okra. In this connection, a genotypic evaluation trial was conducted in okra at the Horticultural College and Research Institute, Dr. YSR Horticultural University, Venkataramannagudem during the year 2014-15. A total of 30 okra genotypes (including two check cultivars) were assessed for genetic divergence using Mahanalobis D2 statistic. Based on the distance values, the population was grouped in to six clusters. Cluster I had the maximum number of genotypes (14) followed by cluster III (7), cluster II and V (3), cluster IV (2) and cluster VI (1). The clustering pattern indicated that there was no association between geographical distribution of genotypes and genetic divergence. The intra-cluster distance was maximum in cluster IV (29.91), while inter-cluster distance was maximum between cluster V and VII (294.67) followed by IV and VI (223.75), thus being a good source for attempting hybridization. The characters namely YVMV infestation, leaf area and fruit yield plant-1 contributed maximum towards genetic divergence therefore, selection of divergent parents based on these characters is recommended for getting good hybrids or desirable segregates in okra. For vegetative character cluster V and VI recorded significantly higher plant height and leaf area, respectively. Regarding fruit character cluster V recorded significantly maximum number of fruits plant-1 and VI recorded significantly higher fruit yield plot-1. With a due consideration on superior performance in respect of certain characters in different clusters, the desirable parents were listed out. The trait fruit yield plant-1 was found to be improved by opting for inter-cluster crosses between V and VI, IV and VI, III and VI, II and VI, IV and V, II and V as well as I and V.
Chandramouli, B., Dorajee Rao, A.V.D., Shrihari, D. and Paratpara Rao, M. (2019). Desirable cross combinations based on cluster analysis among okra (Abelmoschus esculentus Linn.) genotypes. Acta Hortic. 1241, 231-238
genetic divergence, D2 statistics, character contribution, clustering pattern, cross combinations, Ward’s method