Epidemics of stripe (yellow) rust on wheat and triticale fields of Algeria in 2016. Wheat and triticale fields in 69 localities from the eastern regions of Algeria were assessed for epidemics, which started in early march to late may corresponding to booting stage up to early dough stage of the alternative type crop. The infection had incidences ranging from 30 to 100% and severities of 30 to 70%. The newly released cultivar Ksar sbahi was infected up to 10%. The old improved durum cultivars HAR3116 (SHA7/KAUZ) and HAR1407 (COOK/VEES//DOVES) were rust-free at a number of locations. In the Amhara region, the wheat cultivars were at stem elongation to flowering with disease incidences of 50-100% and severities of 30-90%. The oldest cultivar ET 13 A2 was severely infected in the north Shewa zone of Amhara region. Triticale cultivar Logaw Shibo was susceptible at elevations above 2700 m and showed trace reactions at elevations below 2500 m. The local bread wheat cultivar grown in all wheat growing areas was only slightly affected by the disease. Yellow rust was rarely recorded in the Tigray region. Severe epidemics were recorded in the highlands and even at lower elevations where it is not commonly found on wheat.
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farming because of lower demands for pesticide applications. Triticale as a hybrid of wheat and rye may possess disease resistances derived either or both from wheat and rye. In the Czech Republic the leaf rust pathogen isolated from triticale is Puccinia triticina. Triticale is usually resistant to the rye leaf rust pathogen (P. recondita). Limited information is available comparing P. triticina isolates collected from wheat and triticale. Manninger (2006, Acta Phytopathologica and Entomologica Hungarica 41: 93-100) pathotyped 82 isolates collected from wheat and triticale on 15 Thatcher NILs. More than 50% of isolates from wheat were virulent to Lr2b, Lr2c, Lr3, Lr11, Lr17, Lr21 and Lr26. Of 12 isolates from triticale 9 were virulent only to Lr2b and Lr2c and the other 3 isolates were virulent to Lr2b, Lr2c and Lr11. We inoculated 15 NILs and 7 triticale cultivars with 36 Pt isolates from wheat and 36 isolates from triticale. Characteristic differences between the reactions on NILs of isolates from triticale and wheat were not found except that virulence to Lr1 was much more frequent in isolates from wheat. Whereas isolates from triticale were virulent to all 7 tested triticale cultivars, isolates from wheat were virulent to only 3 triticales. In another experiment isolates from wheat and triticale were collected at four locations. Although paired isolates came from the same locations the responses of the NILs were different. Isolates from triticale for all four locations were virulent to a higher number of triticale cultivars than those from wheat. It seems that P. triticina races infecting triticale have changed over the last decade from having a narrow virulence range on bread wheat to the current situation of typical bread wheat races becoming specialized on triticale.