Identification of useful recombinants from interspecific hybrids of Citrullus lanatus and C. colocynthis

Watermelon ( Citrullus lanatus ) is an important fruit crop in the arid region of western India. The modern watermelon cultivars share a narrow genetic base and are susceptible to various stresses. Thus, there is a need to expand its genetic base through distant hybridization by interspecific crossing with C. colocynthis . An attempt was made to develop interspecific hybrids between lanatus and colocynthis followed by hybridity testing of F 1 through SSR markers and biochemical analysis of F 2 . Out of nine primers, eight primers could successfully show amplification in parents and hybrids out of which two markers could correctly discriminate the true hybrid. The morphological analysis demonstrated that F 1 progeny resembles much with C. colocynthis for most of the characters. Biochemical analysis of pulp of selected F 2 plants and parents indicated that in many F 2 plants biochemicals were higher than parents which suggest that the blending of genes from both species made a favourable effect. Diterpene was only present in watermelon and not detected in C. colocynthis or any of the F 2 plants. GC–MS based fatty acid profiling of nine identified fatty acids namely palmitic acid, stearic acid, oleic acid, linoleic acid and linolenic acid was done. It can be concluded that the interspecific hybrids between water melon and C. colocynthis as also confirmed by molecular markers and superior F 2 plants can be used in watermelon breeding program for enhancing vital phytochemicals.