The features of wheat rust development and the resistance of local cultivars in Kazakhstan

The climatic conditions of Kazakhstan are suitable to grow the high-quality grain of spring wheat on an area of 12-14 mil.ha. The country’s sharply continental climate limits the wheat yield as well as biotic stresses. Among latter factors, diseases significantly reduce yield up to 25% and more during epyphytoties. In the Northern Kazakhstan the considerable threat for common wheat comes from leaf rust (Puccinia  triticina), stem rust (Puccinia graminis), septoria (Stagonospora nodorum, Septoria tritici), and tan spot (Pyrenophora tritici-repentis); yellow rust (Puccinia striiformis) infects wheat plants in the South and South-east regions, where the winter wheat is more common. Epiphytoties of leaf rust were observed in 2000, 2002, 2005, and 2007. Many years research has led to conclusion that local wheat varieties do not possess resistance to mentioned diseases. Last year screening of 46 cultivars at Kostanay province designated virulence to local pathotypes, except of couple of them (Kazakhstanaskaya 19 and Karabalykskaya 20). Russian varieties (Omskaya 37, Omskaya 39, Omskaya 41, Uralo-sibirskaya, Pamyati Mayestrenka, Lyubava, and Altayskaya zhnitza) demonstrated “slow rusting”. In the period of 2001-2014 the effectiveness to leaf rust was identified using Thatcher isogenic lines under northern Kazakhstan conditions and showed avirulence to local Pt pathotypes in lines carrying Lr9, Lr24, Lr29, Lr35, and Lr37 as well as the pyramid of Lr genes and/or “slow rusting” genes. The essential spread of stem rust was recorded in 2007, 2008, 2013, and 2014. Taking into account the absence of local sources of infection.  In addition, the monitoring of pathogen with use of a set of lines with Sr genes detected the absence of aggressive race within north of Kazakhstan. In order to create resistant cultivars the sources of resistance are recommended to apply from current study.