One of the major tasks faced by wheat breeders in Uzbekistan is to enhance wheat genotypes’ adaptability to soil and other environmental conditions and improve the grain quality, making the country self-sufficient in wheat grains and later becoming an exporter. Better results are achievable using the world wheat collection, including the CIMMYT germplasm. Determination of the positive correlation of physiological traits of new wheat cultivars, the importance of physiological indicators of water balance with productivity, and the vital role of these indicators in productivity level were the chief concerns. The timely study evaluated heat resilience, rust resistance, and grain yield in bread wheat genotypes. Bread wheat germplasm obtained from CIMMYT with a background of artificial infection of yellow rust incurred scrutiny for their rust resistance. A 15% incidence was detectable in seven genotypes; however, necrosis quickly formed around the symptoms of the disease in plant leaves, preventing its further development. Resistant wheat accessions, i.e., 1088, 1164 (R), 1006, and 1251 (MR), occurred as moderately resistant, showing high leaf area and grain yield. The average value of the genotypes was low, mainly due to the two rust-resistant samples, and the 1000-grain weight was 34.8 g and 34.6 g, respectively, and the grains per spike and grain yield were lower than the average. The chlorophyll a and b, total chlorophyll, carotenoid content, relative water content, flag leaf area, and production traits of the genotypes К-1088 and К-1164 gained assessment, revealed to be physiologically effective under the field conditions of Tashkent, Uzbekistan. Quantitative indicators of the productivity of these wheat genotypes indicated positive differentiation. Selection ensued for promising accessions to develop initial sources for producing the wheat genotypes with rust resistance and high grain yield under the environmental conditions of Uzbekistan.
Bread wheat (T. aestivum L.), wheat yellow rust, rust resistance, heat tolerance, leaf area, chlorophyll a and b, carotenoid, water content, grain yield
By comparing with the standard check, a lower average value of the wheat accessions
was mainly due to the two rust-resistant genotypes, K-1164 and K-1289, which also have 1000-grain weights of 36.1 g and 34.8 g, respectively. The grain yield of these genotypes was also much lower than the average yield. Desirable chlorophyll a and b, total chlorophyll and carotenoid content, relative water content, leaf area of flag leaves, and higher grain yield were substantial in the wheat landraces К-1088, К-1082, and К-1164 and proved to be physiologically effective under environmental conditions of Tashkent, Uzbekistan. Quantitative indicators of the productivity of these accessions provided positive differentiation, with these genotypes recording higher values than the rest of the entries.