Morpho-Physiological Characterization of Interspecific Hybrids in Brassica spp.

Abstract

Brassica is a key agricultural genus, containing oilseed and vegetable crops, which includes three major genomes (A, B and C), distributed in diploid (genomes: AA, BB and CC) and allotetraploid species (genomes: AABB, AACC and BBCC). Inter-specific hybridization between Brassica species is an important way to combine valuable characters from the different species. The present study was carried out in the experimental farm of Bihar Agricultural University, Sabour, Bhagalpur during rabi 2019-20 and 2020-21. In this study wide hybridization were carried out among the Brassica juncea (AABB genome) and Brassica carinata (BBCC genome), Brassica campestris var. toria, yellow sarson, brown sarson with AA genome and Brassica juncea ×  Brassica fruiticulosa for introgression of desirable traits. The direct crosses among Brassica juncea × Brassica carinata, Brassica juncea × Brassica campestris var.toria yellow sarson, brown sarson were successful while, all the reciprocal crosses and the cross between Brassica juncea × Brassica fruiticulosa were not successful. Cyto-morphological characterization was carried out in true wide hybrids along with their parents. There were meiotic irregularities in the microsporogenesis of inter-specific hybrids which was variable with different inter-specific hybrids. All the crosses of interspecific hybrid showed vigour for many of the morphological characters like plant main shoot length, plant height and delayed flowering while rest of the other quantitative characters were found intermediate between the two parents. Among the parents, Brassica carinata showed highest concentration of sinigrin followed by Brassica juncea and lowest was found in Brassica campestris var. yellow sarson. In interspecific hybrids, Brassica juncea × Brassica carinata hybrid exhibited highest concentration of sinigrin while, the hybrid Brassica juncea × Brassica campestris var. yellow sarson showed lowest concentration. The identified hybrids may be used in the future breeding programme for getting aphid tolerance genotypes as well as broadening the genetic base of Brassicas.