Double haploid production for the diversification of restorer lines in Indian mustard (Brassica juncea L. Czern & Coss.)
Loading...
Date
2014
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
CCSHAU
Abstract
Present investigation was carried out to establish the efficient protocols for developing Brassica haploids required for double haploid production in B. juncea. Sixteen media combinations were tried for anther culture in four hybrids of genotypes RH 406, RH 555, RH 749 and RH 832 crossed with Ogura Restorer (OR) as the background Highest per cent callusing anthers were observed on B5 medium supplemented with 100 g/L sucrose + 30 mg/L glutathione + 100 mg/L serine + 0.05 mg/L BAP + 0.5 mg/L NAA + 20 mg/L silver nitrate i.e. (20.80 + 0.34) in genotype OR x RH 832 and maximum shoot regeneration (10.50+0.81) was observed on MS medium fortified with 30 g/l sucrose + 2.5 mg/l Kin + 0.2 mg/l NAA. Most suitable media for anther culture observed were ACM15 and 16.
The present study was also undertaken to develop a regeneration system for four B. juncea genotypes and their F1’s using 5 days old seedling explants i.e. hypocotyls and cotyledons. Both the explants were cultured on MS medium supplemented with different concentrations and combinations of growth regulators. Highest per cent shoot formation was observed on MS medium with 2.5 mg/l Kn and 0.2 mg/l NAA (83.33+5.09) from cotyledonary explants in genotype RH 832. Highest no. of shoots per explant (16.16+0.63) were obtained on MS medium fortified with 2.5 mg/L BAP in OR x RH 406 among all the genotypes and their F1’s. Half strength media were proved to be best media for rooting. Best media for regeneration system was observed to be MS media with 2.5 mg/l Kn and 0.2 mg/l NAA. RH 406 was found to be most responsive genotype among all genotypes and F1’s. Evaluation of Brassica juncea genotypes for yield and its component traits was carried out. Both the phenotypic and genotypic coefficients of variation were higher for important traits including no. of pods on main branch, seed yield/ plant, oil content and 1000-seed weight. High heritability in conjunction with high genetic advance were observed for seed yield/ plant, number of seed yield, oil content, 1000-seed weight and no. of pods on main branch suggesting predominant role of additive gene action for expression of these traits. Seed yield/ plant was found to be positively and significantly correlated with number of primary branches/ plant and number of secondary branches/ plant; seed yield/plant had negative association with pod length and main shoot length. Path analysis revealed that no. of pods on main branch, no. of seeds/siliqua and siliqua density on main shoot had positive direct effect on seed yield/ plant which suggested that selection for these traits would be quite effective in improving seed yield in Indian mustard.
Description
Keywords
planting, genotypes, regeneration, auxins, sowing, developmental stages, yields, biological phenomena, organ culture, genetics