Combining ability and gene action studies for economic traits and disease resistance in linseed Linum usitatissimum L

Abstract

newline The present investigation entitled Combining ability and gene action studies for economic traits and disease resistance in linseed (Linum usitatissimum L.) was undertaken to get the information on nature and magnitude of gene action, combining ability and heterosis and thereby identifying potential parents and cross combinations for seed yield, fibre yield and associated traits under variable environments that could support further improvements of linseed productivity using appropriate breeding methodology. Eight linseed varieties viz., Surbhi, Bhagsu, Nagarkot, T-397, Himani, Baner, JRF-4 and JRF-1 were hybridized following Griffing s Method 2, Model 1 in a half diallel fashion. Experimental materials comprising of eight linseed varieties and 28 F1 progenies were evaluated in RBD with three replications during the year 2016-17 and 2017-18 at Experimental Farm of the Department of Crop Improvement, CSK HPKV, Palampur. Various cross combinations were also examined to study the genetics of resistance to powdery mildew and rust in linseed at Palampur and research station SAREC Kangra, respectively during the year 2017-18. The analysis of variance revealed significant differences among the genotypes for all the traits studied during 2016-17, 2017-18 and pooled over environments, suggesting prevalence of wide range of genetic variability. Variance due to environment in pooled analysis revealed significant differences for all the traits studied except seeds per capsule. Genotype × environment (G × E) interaction was significant for most of the traits except plant height and technical height indicated a definite role of environment on the performance of genotypes. Variances due to GCA, SCA and their interaction with environment were significant for most of the traits. For most of the traits, there was preponderance of non-additive gene action, under such situation diallel selective mating or biparental mating in early segregating generations followed by recurrent selection might be appropriate approach