Multiple Rust Resistance in Triticum aestivum, T. durum, T. dicoccum and Triticale

Abstract

A b s t r a c t A r t i c l e I n f o Wheat and Triticale rusts (leaf stem and stripe) are important diseases in India and other South Asian countries and in regions of world wherever wheat is cultivated. Rusts are known to evolve over time and space and thus making it necessary to breed new wheat and Triticale genotypes with new combination of resistant genes to rusts for effective management of this menace. In India, the evaluation of newly developed wheat varieties against three rusts initiates even before their entry in to the coordinated yield trials besides, evaluation of these in initial and advanced varietal trials at hot spot locations under artificially inoculated conditions. The numbers of resistant entries of the yield trials, identified against three (stem, leaf and stripe) or two rusts (stem and leaf or leaf and stripe) and falling in the range of average coefficient of infection from 0-10.0 in Plant Pathological Screening Nursery (PPSN) were again tested to confirm their resistance during 2003-04 till 2011-12 crop seasons at hot spot locations: Mahableshwar, Wellington, Indore, Dharwad against stem rust, Hisar, New Delhi, Karnal, Ludhiana, Pantnagar, Durgapura in North, Mahableshwar, Indore, Wellington and Dharwad in South against leaf rusts whereas, Karnal, Pantnagar, Durgapura, Almora and Ludhiana in North India, against stripe rust. These lines have wide genetic base and those identified in AVTs are quite good in agronomic characters. Out of 741 genotypes tested, 460 numbers were found to possess multiple rust resistance. A total of 315 were resistant to stem, leaf and stripe rusts, 90 to stem and leaf rusts and 55 to leaf and stripe rusts. Out of these, 364 of bread wheat (T. aestivum), 71 of macaroni wheat (T. durum), 11 of khapali wheat (T. dicoccum) and 14 genotypes of Triticale were resistant to two or three rusts. These include both types of genotypes falling in the category of ACI 0.0-5.00 and 5.110.0 and are used in breeding for rust resistance in India. A total of 20 such genotypes are already released as high yielding rust resistant varieties in India. The seeds of these are kept in gene banks of IIWBR, Karnal and National gene bank at NBPGR, New Delhi.