One of the factors affecting wheat productivity in Tajikistan is the emergence and spread of rust diseases - yellow, stem and leaf rust. Emerging new races of pathogens virulent to existing resistance genes in wheat varieties create new challenges. The selection of rust resistant wheat genotypes is usually carried out by studying phenotypic traits in seedlings (seedling resistance) and in adult plants (adult plant resistance) and analysis using available molecular markers. It has been established that races of yellow rust affecting wheat varieties in Tajikistan are aggressive and are characterized by high temperature tolerance. According to the results of studies, it was found that the highest degree of resistance to yellow rust is observed in varieties Sarvar, Vakhdat, AIKT-20 and Fayzbakhsh, in old-grown varieties Kaboi Pandzhakent and Surkhak-5688, as well as in the line PASTOR/3/VORON. Most of the new wheat varieties have the following groups of rust resistance genes: Sr31/Yr9/Lr26, Sr38/Yr17/Lr37, Yr30/Sr2/Lr27 и Yr18/Lr34/Sr5. In this regard, it is necessary to constantly monitor the spread and development of rust diseases, as well as to select wheat varieties for resistance to rust using both traditional and modern methods using molecular markers.
Non-satisfactory bread-making quality in wheat, a Tajik staple, hampers food security in Tajikistan and calls for plant breeding efforts. Here, methods were searched for to study grain protein composition, which is of use for Tajik plant breeding to improve bread-making quality. Size-exclusion high-performance liquid chromatography (SE-HPLC) was used to determine protein composition in 22 wheat varieties and breeding lines grown in two locations, which were then compared with the specific protein composition evaluated using electrophoresis and previous results from Tajik breeding and farmer-grown wheat. As Tajik wheat generally showed a large variation in high-molecular-weight glutenin subunit (HMW-GS) composition, with several allelic variants in the same line, single-seed selection was required when using this methodology in breeding for improved bread-making quality, and such an evaluation willalso result in more homogenous lines for protein composition. SE-HPLC was found to be a suitable tool to evaluate protein composition in the current Tajik wheat material with a heterogeneous protein composition, which might be advantageous for adaptation to the local and future climate. However, more easy-to-handle and high-throughput methods, e.g., marker-assisted selection, could be preferable alternatives for studying protein composition in wheat and for use in breeding for increased bread-making quality to increase food security in Tajikistan.