Application of clustering technique in mango and litchi germplasm of West Bengal.

Abstract

Field experiments were conducted in West Bengal, India, to identify genetically divergent groups pertaining to dwarfness in 19 mango cultivars and selection of genetically divergent germplasm in Litchi chinensis breeding programmes by the application of clustering techniques. In mango, different clusters were obtained through the application of Ward's method under Euclidean distance. Roughly all the 19 mango cultivars along with their average were grouped into 3 clusters based on 3 traits. Except the middle cluster with the cultivars Bombai, Himsagar and Langra, the remaining 2 clusters were further grouped into 2 subclusters. All the 3 clusters were considered as genetically divergent groups of mango cultivars. The members of these clusters may be useful in hybridization programmes. In L. chinensis, different clusters were obtained through the application of average within group linkage method under squared Euclidean distance. Altogether, there were a total of 7 clusters. Cluster II (SG_JAL4), cluster VI (SG_JAL8) and cluster VII (SG_JAL6) each had a single member germplasm. These germplasms were highly genetically divergent from the germplasms of other clusters. These may be considered as the base population for selection of genetically divergent germplasm in L. chinensis breeding programmes.