A.M. ABEKOVA, R.S. YERZHEBAYEVA, S.O. BASTAUBAYEVA, K. KONUSBEKOV, T.A BAZYLOVA., D.I. BABISSEKOVA, and A.A. AMANGELDIYEVA SUMMARY Sugar beet is a highly valuable and profitable crop in the Republic of Kazakhstan. It is the only source of raw materials for the production of crystalline sugar and incidentals (tops, bagasse, and molasses).

Leaf rust (Puccinia triticina Eriks) is a wheat disease causing substantial yield losses in wheat production globally. The identification of genetic resources with permanently effective resistance genes and the generation of mutant lines showing increased levels of resistance allow the efficient incorporation of these target genes into germplasm pools by marker-assisted breeding. In this study, new mutant (M₃ generation) lines generated from the rust-resistant variety Kazakhstanskaya-19 were developed using gamma-induced mutagenesis through 300-, 350-, and 400-Gy doses. In field trials after leaf rust inoculation, 75 mutant lines showed adult plant resistance. These lines were evaluated for resistance at the seedling stage via microscopy in greenhouse experiments. Most of these lines (89.33%) were characterized as resistant at both developmental stages. Hyperspectral imaging analysis indicated that infected leaves of wheat genotypes showed increased relative reflectance in visible and near-infrared light compared to the non-infected genotypes, with peak means at 462 and 644 nm, and 1936 and 2392 nm, respectively. Five spectral indexes, including red edge normalized difference vegetation index (RNDVI), structure-insensitive pigment index (SIPI), ratio vegetation index (RVSI), water index (WI), and normalized difference water index (NDWI), demonstrated significant potential for determining disease severity at the seedling stage. The most significant differences in reflectance between susceptible and resistant mutant lines appeared at 694.57 and 987.51 nm. The mutant lines developed were also used for the development and validation of KASP markers for leaf rust resistance genes Lr1, Lr2a, Lr3, Lr9, Lr10, and Lr17. The mutant lines had high frequencies of “a” resistance alleles (0.88) in all six Lr genes, which were significantly associated with seedling resistance and suggest the potential of favorable haplotype introgression through functional markers. Nine mutant lines characterized by the presence of “b” alleles in Lr9 and Lr10—except for one line with allele “a” in Lr9 and three mutant lines with allele “a” in Lr10—showed the progressive development of fungal haustorial mother cells 72 h after inoculation. One line from 300-Gy-dosed mutant germplasm with “b” alleles in Lr1, Lr2a, Lr10, and Lr17 and “a” alleles in Lr3 and Lr9 was characterized as resistant based on the low number of haustorial mother cells, suggesting the contribution of the “a” alleles of Lr3 and Lr9.

Genetic variability in micronutrients is limited in wheat varieties. To broaden variation, seeds of cv. Eritrospermum-35 were irradiated with 100 and 200 Gy using 60Co, the treated seeds were grown to M7 generation with successive selection of the highest yield lines in each generation. Selected lines were evaluated for yield and grain quality traits such as iron, zinc and phytic acid concentrations, calculation of molar ratios of PA:Fe and PA:Zn. A number of mutant lines had 2 to 3 times more iron and zinc concentrations and lower phytic acid concentration (1.1-3.5 times) and higher protein content (11.2-12.4%) relative to the parent were identified. Some M7 lines showed significantly larger grain weight (1.3-1.5 times) and number per spike (2.0-2.1 times) than the parent. There were significant correlations between zinc and iron concentrations, between grain protein content, zinc, iron and phytic acid concentrations and grain weight per spike, mainly in 100 Gy-dosed lines. The TaPhyllc cDNAs nucleotide and protein sequence similarities between parent and these M7 lines varied from 28.2% and 30.2% to 45.7% and 56.5%, respectively. The results clearly indicate that variability in grain nutrients and metals bioavailability in mutation resource is potential in wheat improving nutritional outcomes and overcome malnutrition.

The objective of this study was to broaden genetic variation of spring common wheat, evaluate and identify among M5 mutant lines those with high-yield and improved grain quality characteristics. New lines were generated by initial treatment of variety of Eritrospermum-35 adapted to conditions of Kazakhstan by irradiation with 100-Gy and 200-Gy doses from a 60Co source. Yield-associated traits including grain number and weight per main spike, grain weight (GW) per plant, and the thousand-kernel weight; grain size and grain shape variations; as well as quality characteristics such as grain protein content (GPC), iron, and zinc concentrations were evaluated. Mutant lines with high iron and zinc concentrations and high protein content were identified as those which have 1.6–3.4 and 1.4–2.9 times more as well as 3.7–16.9% more higher data of target concentrations than parental variety had, respectively. Several mutant lines showed significant increase in both grain iron and zinc concentrations. The positive correlation of grain quality parameters with grain area, length, and width suggest that they are related to each other. Wheat grain can be biofortified with micronutrients without negative impact on crop productivity using new mutant lines. Mutation breeding can significantly contribute to human health malnutrition and improve nutrition quality diet.

Genetic variability in bread wheat concerning grain nutritional quality and physical morphometric parameters, which is a required prerequisite to improve modern varieties is limited. It is also important to combine the improved grain quality characteristics with tolerance to abiotic and biotic stresses including fungal disease such as yellow rust, the most common wheat disease that significantly reduces its production. The goal of present study was to broaden the genetic variation of spring bread wheat on the basis of a rust resistant cv. Kazakhstanskay-19 and mutational selection. The doses of gamma irradiation of 300 Gy, 350 Gy, and 400 Gy treatments were applied to develop new M4 mutant lines and search advanced resources which combine yellow rust resistance, improved grain morphometric parameters, and high grain protein content. The 300 Gy and 350 Gy radiation doses showed a significantly highest effect in an increase in grain area with the same level of action, showing its increased efficiency to cause mutations in the genes related to with this grain characteristics. The grain features such as length recorded significant variation only through 300 Gy treatment, indicating that only this lowest dose is effective for the improvement comparing with the higher level of radiation. Key words: genetic variation in grain nutritional quality, physical morphometric parameters, spring wheat, grain protein content.

The increasing threat posed by wheat rust diseases caused by Puccinia spp. necessitates the development of resistance strategies that extend beyond conventional race-specific mechanisms. Although recent reviews (2023–2025) have emphasized gene discovery and genomic approaches, comparatively less attention has been given to the potential roles of metabolic regulation and micronutrient homeostasis in host–pathogen interactions. Here, we present a narrative synthesis of current evidence and propose a conceptual framework in which induced mutagenesis (ethyl methanesulfonate, EMS, and γ-irradiation) serves as a tool for investigating interactions among redox regulation, iron (Fe) homeostasis, and disease resistance. A key component of this framework is the proposed interplay between reactive oxygen species (ROS) signaling and Fe partitioning. Vacuolar iron transporters (VITs), ferritins, and associated transport networks regulate intracellular Fe distribution and may influence Fe availability at the host–pathogen interface, potentially affecting fungal development and host defense responses. This concept of “iron-withholding immunity” may operate alongside ROS-mediated defense processes, linking metabolism with immune function. Observations from mutant wheat populations are broadly consistent with the hypothesis that these processes may contribute to durable adult-plant resistance (APR), which is characterized by reduced disease development, coordinated defense responses, and relative stability across environments. In some studies, Fe-enriched mutant lines have been associated with enhanced expression of pathogenesis-related genes and the occurrence of combined APR and seedling-resistance phenotypes, suggesting possible links between micronutrient homeostasis and immunity. Integration of high-throughput phenotyping with genotype × environment × time (G × E × T) frameworks may further improve our understanding of quantitative resistance and disease-associated traits. Overall, this review highlights the potential importance of nutrient homeostasis, redox regulation, and susceptibility modulation as components of future research aimed at developing climate-resilient and nutritionally improved wheat cultivars.