Marker assisted introgression of QTL region to improve late leaf spot and rust resistance in elite and popular variety of groundnut (Arachis hypogaea L.) cv TMV 2

Late leaf spot (LLS) and rust diseases are the major devastating diseases in groundnut that lowers crop yield and fodder quality. Marker assisted backcross breeding was employed to introgress LLS and rust diseases resistance QTL region from GPBD 4 into an India’s popular groundnut variety TMV 2. The MABC approach was exercised using a total of eight disease resistance-linked markers viz.., IPAHM103, GM1573, GM1009, Seq8D09, GM2009, GM1536, GM2301 and GM2079 present in the QTL region. After three backcrosses and selfing, a total of 155 BC3F2 lines were developed from the cross TMV 2 x GPBD 4. Ten BC3F2 homozygous introgression lines were identified with resistance QTL region and subjected to background analysis. A genome recovery upto 99.80% was observed among introgression lines and advanced to further generations for field evaluation. Finally, six ILs with enhanced late leaf spot and rust diseases resistance were identified. Those ILs had significantly increased pod yield (42–65%) over the recurrent parent TMV 2 with enhanced resistance to LLS and rust diseases. Multi-location field evaluation of these ILs could leads to the release of improved varieties and also can be used as genetic resources in the groundnut improvement.