New Common Winter Wheat Lines with Resistance to Leaf Rust (P. triticina)

Wheat is the most important cereal crop in global agricultural economy and is cultivated in diverse agroclimatic regions of the world. Breeding for disease resistance is the most economically and environmentally safe method to reduce crop losses. The long term success of breeding for disease resistance depends on the nature of the pathogen and the virulence spectra in the pathogen population, the availability, diversity and type of genetic resistance in the host and the methodology for screening and selection for resistance. During 2013-2015, under conditions of an infection field at Dobrudzha Agricultural Institute - General Toshevo, Bulgaria, 680 common winter wheat lines were tested to a population of races of leaf rust P. triticina.Forty - two of the lines, which exhibited resistance under field conditions, were tested to 9 pathotypes of the pathogen at seedling stage under controlled conditions. Some of the tested lines carried adult plant resistance (APR), while others had combination of race specific and race nonspecific resistance. The combination of various mechanisms of resistance is of great importance for the durability of resistance. In this relation, the investigated 42 lines can be considered efficient sources of resistance which can be used in the breeding programs