Phenotyping of Groundnut Genotypes in Different Environments to Identify Resistant Sources of Alternaria Leaf Blight

Abstract

Alternaria leaf blight is new emerging foliar fungal disease of rabi-summer groundnut, no groundnut genotypes reported to resistant to this disease. With this objective a total 36 shortlisted groundnut genotypes including interspecific derivatives; advanced breeding lines and recommended cultivars of rabi-summer season were screened under artificial epiphytotic conditions during four summer 2017, 2018, 2019 and 2020. Four years rigorously screening results indicated that four interspecific derivatives (NRCGCS 176, NRCGCS 180, NRCGCS 196, NRCGCS 298), four advanced breeding lines (PBS 12190, PBS 22131, PBS 22132 and PBS 22133) and one cultivar ICGV 00348 recorded a disease score ≤ 3 on 1-9 scale against score 7 of susceptible check (Narayani, Dh 86, GG 2, GJG 31). Hence, these groundnut genotypes identified as a novel source of resistance to Alternaria leaf blight. These can be used in breeding programme to develop resistant groundnut varieties. In addition to cultivar viz., Kadiri 9, Kadiri Haritandhra, GJG 17 and ICGS 44 also had a disease score of 4 and thus reported to be medium resistant to Alternaria leaf blight. These cultivars may be recommended directly for cultivation in high disease affected groundnut areas. Based on the yield and resistant to Alternaria leaf blight, ICAR- Indian Institute of Groundnut Research, Junagadh is being utilizing two resistance sources (PBS 22131 and NRCGCS 298) in groundnut breeding for developing high yielding Alternaria leaf blight resistance varieties.