[Occurrence and virulence of wheat rusts in Syria]
1995
El-Naimi, M. | Mamluk, O.F.
The occurrence of the three wheat rusts in Syria was monitored during ten growing seasons, 1983/84 - 1992/93. Yellow rust (Puccinia striiformis) is the most prevalent and damaging rust in the country and occured in every season. Epidemics of yellow rust are expected when the disease occurs early in the season (February) and the environmental conditions in Spring are favorable. The season 1987/88 was marked by a severe epidemic of yellow rust and caused high grain losses. Bread wheats were more affected than durum wheats. Six physiological races of yellow rust were identified. Effective resistant genes are Yr1, Yr3v, St. Dikkopf, Yr4+, Yr6+, Yr3N, Carstens V, Sp. Prolific, T. sp. album and Cham 1. Leaf rust (P. recondita) occured in nine of the ten seasons. An epidemic occured during the 1990/91 season. Leaf rust is endemic in the Ghoulan and the southern region of Syria. Durum wheats are generally more affected by leaf rust than bread wheats. Four physiological races of the leaf rust were found frequently. Effective resistant leaf rust genes are Lr19, Lr20, Lr24. Stem rust (P. graminis) occurred in seven of the ten seasons and its effect on wheat crop is negligible because it usually starts late in the season. Two physiological races of stem rust were identified.
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