Characterization of Pyrenophora tritici-repentis (tan spot of wheat) races in Kazakhstan

Abstract

Tan spot, caused by Pyrenophora tritici-repentis, is an economically important foliar disease of wheat in Kazakhstan. Population structure of the pathogen changes every year due to climate change. This study aimed to characterize the race structure of P. tritici-repentis isolates recovered from wheat in south and north Kazakhstan, and identify tan spot resistance in host genotypes based on disease phenotypes and molecular screening. Virulence profiles were determined within 40 isolates of the pathogen from wheat crops during the 2020 growing season. Seven races, (1, 3, 4, 5, 6, 7 and 8) were identified. A collection of 80 wheat accessions, including promising lines and cultivars from Kazakhstan and Russia, were evaluated for their reactions to races 1 and 5 of the pathogen, and to Ptr ToxA and Ptr ToxB, using greenhouse assessments and molecular markers diagnostic for the Tsn1 and Tsc2 genes. From a practical viewpoint, 18 wheat genotypes were insensitive to the two races and the two Ptr toxins. This resistant germplasm can be used in breeding programmes aiming to develop wheat varieties resistant to P. tritici-repentis.

Phenotyping and Identification of Molecular Markers Associated with Leaf Rust Resistance in the Wheat Germplasm from Kazakhstan, CIMMYT and ICARDA

“…Currently, moderate disease development of P. triticina is observed on the territory of Southern Kazakhstan [14]. In addition to leaf rust [15][16][17], diseases such as tan spots [18][19][20][21], yellow rust [22][23][24][25], and stem rust [26,27] are also widespread.…”

Identification of Sources of Resistance to Septoria Tritici in Winter Wheat Germoplasm

“…In recent years, the increasing use of tillage practices that leave large amounts of wheat stubble and debris on the soil surface has increased the likelihood of Septoria blotch epidemics occurring under favorable climatic conditions and is therefore expected to occur more frequently in the future in developing countries. In the Almaty region in recent years, rust diseases have predominated, as well as leaf spot diseases (tan spot, septoria blight) [3][4][5][6].…”

Characteristics of Perspective Wheat Cultivars, Admitted to Cultivation in the Lower Volga Region of the Russian Federation, Based

“…Наиболее рациональным методом защиты пшеницы от листовых пятнистостей служит возделывание и использование устойчивых сортов. В связи с широким распространением и вредоносностью этих заболеваний, многие научные работы посвящены поиску образцов зерновых культур, устойчивых к указанным патогенам (20)(21)(22). Однако в большинстве случаев выявленных устойчивых образцов пшеницы недостаточно.…”