Races Identification of Wheat Rusts in Syria during the 2019 Growing Season

Kharouf, Sh., Sh. Hamzeh and M.F. Azmeh. 2021. Races Identification of Wheat Rusts in Syria during the 2019 Growing Season. Arab Journal of Plant Protection, 39(1): 1-13. Wheat rust diseases, caused by Puccinia striiformis f. sp. tritici (stripe or yellow rust), P. triticina f. sp. tritici (leaf or brown rust) and P. graminis f. sp. tritici (stem or black rust) are important factors affecting both durum and bread wheat production in Syria. Considerable losses were caused by these diseases, especially stripe rust, estimated at more than one million metric tons, in the 2010 season, out of 5 million anticipated production. Therefore, it is essential to monitor and follow the movement of these three rust physiological races. In the 2019 growing season, 165 wheat fields were surveyed, and 312 samples were collected and characterized. Ten races of stripe rust were identified in ten locations, of which, four represent new record in Syria, namely the races 16E154, 69E150, 264E46 and 258E64. In addition, four races of leaf rust were identified in four locations, one of which (BKLP) is a new record in Syria. In addition, three previously recorded stem rust races were identified from three different locations. It should be mentioned that the newly recorded races of stripe rust are able to overcome resistance genes Yr1 and Yr5, on which the resistance of durum wheat cultivars such as "Cham3" depended, with a disease severity of 40S recorded in the same locations. It is also worth noting that the stripe rust race 462E128 (warrior) was not detected in the isolates studied. Likewise, the stem rust race Ug99 was also not identified, and because of the aggressiveness of this race, continuous inspection through field surveys accompanied with pathogenicity tests is essential during the coming seasons. Keywords: Stripe (yellow) rust, Leaf (brown) rust, stem (black) rust, race identification, wheat, Syria