Identification of blast resistance in a core collection of foxtail millet germplasm

Blast, also known as leaf spot, caused by Pyricularia grisea [teleomorph: Magnaporthe grisea], is a serious disease affecting both forage and grain production in foxtail millet in India. For the identification of new and diverse sources of blast resistance, a foxtail millet core collection comprising 155 accessions was evaluated against Patancheru isolate (Fx 57) of M. grisea. In a field screen during 2009 and 2010, 21 accessions were identified with neck and head blast resistance against Fx 57. In a greenhouse screen, 11 of the 155 accessions exhibited seedling leaf blast resistance to the same isolate. Further evaluation of the selected 28 accessions (found resistant to neck and head blast under field conditions during 2009 and 2010, and/or leaf blast in the greenhouse screen) against four M. grisea isolates Fx 57, Fx 58, Fx 60 and Fx 62 from Patancheru, Nandyal, Vizianagaram and Mandya, respectively, led to the identification of 16 accessions with leaf, sheath, neck and head blast resistance to at least one isolate. Two accessions (ISe 1181 and ISe 1547) were free from head blast infection and showed resistance to leaf (score ≤3.0 on a 1-to-9 scale), neck and sheath blast (score ≤2.0 on a 1-to-5 scale) against all the four isolates. In addition, ISe 1067 and ISe 1575 also exhibited high levels of blast resistance. Blast-resistant accessions with superior agronomic and nutritional quality traits can be evaluated in multilocation yield trials before releasing them for cultivation to farmers