Recessive genes controlling resistance to Helminthosporium leaf blight in synthetic hexaploid wheat

A study was conducted under controlled environment conditions in a phytotron to determine the nature of the inheritance of resistance Helminthosporium leaf blight (HLB) in a synthetic hexaploid wheat line, 'Chirya-3', against the isolate KL-8 of Bipolaris sorokiniana from the major wheat growing region of India. Crosses were made between two susceptible lines 'WH 147' and 'Chinese Spring'. Analyses of F 1 and F 2 populations of these two crosses ('WH 147' × 'Chirya-3' and 'Chinese Spring' x 'Chirya-3') showed that resistance against the isolate in 'Chirya-3' was governed by two recessive genes functioning in a complementary interaction giving an F 2 segregation pattern of 1: 15 (resistant: susceptible). The segregation pattern of the resistant F 2 progenies in F 3 families from both crosses confirmed that two homozygous recessive genes were responsible for resistance to the isolate of Bipolaris sorokiniana in the synthetic line 'Chirya-3'. It is proposed that the genes be designated as hlbrl and hlbr2.