Molecular characterization of rust resistance introgressed into Linum usitatissimum L from its wild and cultivated gene pool

Abstract

newline The research endeavour entitled and#8213;Molecular characterization of rust resistance introgressed into Linum usitatissimum L. from its wild and cultivated gene pooland#8214; was executed in the Department of Crop Improvement, CSK HPKV, Palampur and Agricultural Research and Extension Centre (SAREC), Kangra during the years 2012-13 to 2016-17 with the objective to evaluate the crossability of different wild species with its cultivated species, transfer resistance against linseed rust, study the genetics of rust resistant gene(s), identify molecular markers linked to rust resistance gene(s) and nature and magnitude of gene effects for yield and its component traits. The experimental material comprised of six cultivated varieties of L. usitatissimum L. namely T-397, Chambal, Kangra Local, HimAlsi-1, Nagarkot and HimAlsi-2 and two wild species viz., L. angustifolium and L. grandiflorum. Interspecific hybridization revealed that L. angustifolium is crossable with cultivated varieties and has shown maximum crossability of 78.00 and 79.13 percent during 2012-13 and 2013-14, respectively at the temperature range of 10.00 to 24.70°C. The highest seed formation efficiency was observed in cross HimAlsi-2 x L. angustifolium (52.00 and 49.05 percent during 2012-13 and 2013-14 respectively ) at the temperature range of 5.91-22.43°C. The interspecific and intervarietal hybrids developed involving T-397 x L. angustifolium and T-397 x HimAlsi-1, were true to type based on confirmation at the morphological and molecular level. Inheritance of rust under natural epiphytotic conditions in T-397 x L. angustifolium and T-397 x HimAlsi-1 indicated the involvement of single dominant gene for disease resistance. Linkage analysis of the F2 mapping population revealed that the forward marker locus OPA 18 and reverse locus JA23 and rust resistance gene are located 5.8cM and 3.4cM apart, respectively for T-397 x L. angustifolium, whereas, in case of T-397 x HimAlsi-1 it was 1.9cM (OPA 18) and 3.3cM (JA 23) apart from the rust resistance gene. Fu