Combining Ascochyta blight resistance and high yield in lentil cultivars

Abstract

Ascochyta blight (AB), caused by Ascochyta lentis Bond and Vassil, is a major disease of lentil (Lens culinaris L. Medik.) causing 30–70% yield losses in Canada, USA, and Australia and northern parts of India. The aim of the present study was to combine AB resistance with high yielding potential. The F3 and F4 populations from crosses involving AB resistant donors with ICARDA elite breeding lines, were advanced at Punjab Agricultural University, Ludhiana, India, respectively during main and off-seasons. The single plant F5 progenies were exposed to AB infections under eld conditions during 2006–2007 using disease rating scale of 1-9. Thirty two promising lines, bulked in F7 generation, were evaluated for seed yield in multi-location trials (2009–2010 and 2010–2011) and for their reactions to AB under arti cial inoculations along with susceptible check, LL147 (8 score). Six elite lines namely LL1187 (1.70 t ha-1), LL1210 (1.75 t ha-1), LL1197 (1.76 t ha-1), LL1186 (1.76 t ha-1), LL1201 (1.80 t ha-1) and LL1205 (1.80 t ha-1) recorded 9.6–16.1% yield advantage over the best check variety LL931 (1.55 t ha-1). The level of resistance (≤ 4 score) of these lines to AB was also higher compared to check variety LL931 (5 score). Inheritance of AB resistance is simple and controlled by major genes; hence it is easy to incorporate stable resistance in high yielding background by selecting parents carefully for hybridization program.