Studies on Genetic Divergence for Yield and Quality Traits in Cucumber (Cucumis sativus L.)
Om Prakash Kumawat
Department of Horticulture, Rajendra Prasad Central Agricultural University, Pusa, India.
Udit Kumar *
Department of Horticulture, Rajendra Prasad Central Agricultural University, Pusa, India.
Satish Kumar Singh
Department of Plant Breeding and Genetics, Rajendra Prasad Central Agricultural University, Pusa, India.
Sooraj Maurya
Department of Horticulture, Rajendra Prasad Central Agricultural University, Pusa, India.
Sooraj Maurya
Department of Horticulture, Rajendra Prasad Central Agricultural University, Pusa, India.
B. M. Sinha
Department of Horticulture, Rajendra Prasad Central Agricultural University, Pusa, India.
*Author to whom correspondence should be addressed.
Abstract
Genetic divergence analysis, using Mahalanobis D2 statistics, was carried out in twenty one cucumber genotypes including one check for fourteen characters. All the characters under study showed considerable divergence and the genotypes were grouped into four clusters. The clustering pattern had no parallelism between genetic diversity and geographical distribution, suggesting that the selection of parental genotypes for hybridization will be more appropriate based on genetic diversity. Cluster III contained the maximum (5) number of genotypes, whereas remaining all clusters I, II and IV contained similar (4) genotypes. The Intra-cluster distance was maximum (306.685) in cluster III whereas, it was minimum (163.11) in cluster II. Maximum average inter-cluster distance (1439.432) was recorded between cluster IV and cluster V, suggesting the greater chances of getting superior hybrids in F1 or transgressive segregants in subsequent generations. Genotypes in cluster IV were superior in node number of first female flower, days to first flowering, shelf-life, TSS, fruit length, fruit weight and fruit yield per plant. Cluster V had superiority in terms of vine length and number of seeds per fruit. Fruit weight, TSS, number of seeds per fruit, node number of first female flower, shelf-life, days to first harvest and days to first flowering contributed towards genetic divergence.
Keywords: Cucumber (Cucumis sativus L.), genotype, divergence, mahalanobis and cluster.