Molecular-agronomic characterization and genetic study reveals usefulness of refined Ogura cytoplasm based CMS lines in hybrid breeding of cauliflower (Brassica oleracea var. botrytis L.)

Doubled haploid based parental lines are most suitable in predicting heterosis using microsatellites and in development of highly heterotic F1hybrids inBrassica oleracea

“…The 20 Ogura CMS lines, 6 DH testers along with their 120 test cross progenies were evaluated for sixteen agro-morphological traits viz. (i) days to 50% curd initiation: Days to 50% CI) (ii) days to 50% curd maturity: Days to 50% CM (iii) plant height: PH (cm) (PH) (iv) gross plant weight: GPW (g) (v) marketable curd weight: MCW (g) (vi) net curd weight: NCW (g) (vii) leaf length: LL (cm) (viii) leaf width: LW (cm) (ix) number of leaves: NoL (x) curd length: CL (cm) (xi) curd diameter: CD (cm) (xii) core length: CoL (cm) (xiii) curd size index: CSI (cm 2 ) (xiv) leaf size index: LSI (cm 2 ) (xv) harvest index: HI (%) (xvi) Total marketable yield: TMY (t/ha) [13-15, 17]. Data were recorded from 5 randomly selected plants of each genotype of each plot/block of all the three replications.…”

“…Great efforts have been made to improve the productivity and quality of this crop, ascribed to its economic value and as an essential component of healthy diet [91]. The replacement of open pollinated varieties with F 1 hybrids have become much pronounced in cole vegetables including cauliflower due to high uniformity, better quality, tolerance to various biotic stresses and vagaries of adverse climatic conditions [17, 69]. It is well established that Brassica vegetables exhibit a wide range of heterosis and high heterosis have been reported in cauliflower also for both yield and quality traits [13, 15, 69].…”

“…It is well established that Brassica vegetables exhibit a wide range of heterosis and high heterosis have been reported in cauliflower also for both yield and quality traits [13, 15, 69]. Nature has bestowed Brassica vegetables with genetic mechanisms of sporophytic self-incompatibility (SI) and cytoplasmic male-sterility (CMS), which have efficiently triggered the hybrid breeding programme in these crops [13, 15, 17, 66, 69, 77]. However, in the current scenario of increasing temperature as a result of global warming there is frequent breakdown of self-incompatibility, as S-alleles are more prone to high temperature.…”

“…In addition, the maintenance of S-allele lines is time consuming and costly endeavor and in case of snowball cauliflower, SI system is very poor or absent [66, 68]. Under these circumstances, the genetic system of CMS provides a better alternative for heterosis breeding in cole crops [17, 69]. Heterosis or hybrid vigor, plausibly results from accumulation of parental genetic and epigenetic information, is manifested as superior performance of hybrid offspring relative to the average of their genetically diverse parents [3, 26, 45].…”

“…The estimation of SCA is associated with non-additive effects (dominance effects, additive×dominant and dominant×dominant interactions). Among different biometrical approaches, line × tester analysis appears to be ideal for estimating GCA effects of lines and testers, SCA effects of cross combinations, and providing information about nature of gene actions [17, 20, 41]. The extent of heterosis has been reported to be vary with mode of reproduction, genetic distance of parents, traits under investigation, developmental stage of plant and prevailing environment [27, 34, 38, 40, 44, 73].…”