Identification and transfer of powdery mildew resistance from related species into cultivated wheats (Triticum aestivum)

A study was conducted during 1990-98 to identify new sources of powdery mil dew (Erysiphe graminis DC f sp tritici E. Marchel) resistance among 4 wild and 1 related species of wheat (Triticum aestivum L. emend. Fiori & Paol.). Testing at adult plant stage under natural conditions as well as at Seedli ng stage using single spore isolates identified 26 sources of resistance am ong Triticum araraticum (9),;T: boeoticum (1), Aegilops speltoides (14), A. squarrosa ( 1) and T. dicoccum (1). This resistance of two accessions of T : araraticum (Accessions 4697 & 4698) has been transferred into I: durum De sf and 'NP 200' T. dicoccum into 'HD 2329' T. aestivum through interspecifi c hybridization. One backcross derivative carrying resistance from T ararat icum (Accession 4698) showed multiple resistance to powdery mildew, leaf ru st, stripe rust and stem rust under natural conditions at Wellington (Tamil Nadu).