Development of water-stress-tolerant rice (Oryza sativa L.) cultivars is imperative to ensure food security. With this background, 36 rice genotypes comprising six parental genotypes and 30 advanced rice populations underwent water-stress tolerance evaluation using water-stress and irrigated field conditions. Significant (p ≤ 0.05) differences were evident among the genotypes, environments, and genotype-by-environment interactions for yield-related traits. Yield depreciation of rice genotypes under water-stress conditions varied depending on their genotypic tolerance potential. Stress tolerance indicators, such as stress susceptibility index (SSI), stress tolerance index (STI), and yield index (YI), along with the principal component analysis (PCA), served to identify water-stress-tolerant genotypes. For water-stress conditions, the highest grain yield per plant (GY) and desirable stress tolerance indices resulted in G09 (GY = 25.56 g; SSI = –0.36; STI = 1.23; YI = 1.45), G31 (GY = 21.16 g; SSI = –1.50; STI = 0.69; YI = 1.20), G32 (GY = 22.36 g; SSI = –0.59; STI = 0.90; YI = 1.27), and G34 (GY = 21.88 g; SSI = –1.40; STI = 0.75; YI = 1.24). These promising genotypes can be favorable for the development of water-stress-tolerant cultivars through future breeding programs.

Keywords: Rice (O. sativa L.), advanced rice populations, genotype-by-environment interactions, water-stress tolerance, water-stress-tolerance indices, grain yield

Key findings: Newly developed rice (O. sativa L.) genotypes G09, G31, G32, and G34 displayed water-stress-tolerance profiles with the highest grain yield and desirable stress tolerance indices.

This study presents an evaluation of the variability for seed oil content and the relationship among the economic traits of sunflower (Helianthus annuus L.) F₃ populations under the environmental conditions of Karakalpakstan, Uzbekistan. Under simulated drought conditions, complex hybrids provided the basis for transgressive families due to high heterozygosity. It shows the location of families with high oil content was on the right side, making the selection in the sunflower F₃ simple and complex hybrid families. A moderate and high positive correlation existed between root mass and productivity traits, while a high positive correlation occurred between root mass and plant height. Moreover, a moderate positive correlation showed between root mass and head diameter, and varied correlations appeared between root mass and the total leaf surface area. The results revealed a weak to moderate negative correlation between the seed oil content and head diameter in the plants. The correlation analysis of seed oil content variability and the relationship of economically valuable traits in sunflower F₃ hybrid families indicated that larger heads correspond to lower oil content in most cases.

Keywords: Sunflower (H. annuus L.), simple and complex hybridization, variability, correlation analysis, root mass, productivity, plant height, leaf surface area, oil content

Key findings: Through complex hybridization, the sunflower (H. annuus L.) F₃ families with high oil content attained selection under simulated drought conditions. The complex hybridization and high heterozygosity provided the basis for the emergence of transgressive segregants.

Mung bean (Vigna radiata L.) is a susceptible legume species to pod shattering, posing a high risk of yield loss. This study aimed to evaluate the agronomic traits and pod-shattering resistance of IPB mung bean lines. The research, conducted at the IPB University, Bogor, Indonesia, involved the evaluation of 17 IPB mung bean lines and three comparison varieties. Observed traits included growth and yield components, as well as pod-shattering resistance under three conditions: the field, sun-drying (14 days), and oven drying (at 40 °C for seven days). Genetic variability among the lines was found for plant height, days to flowering, seed weight per pod, and pod length. All IPB mung bean lines were grouping into three main clusters based on cluster analysis. Growth traits and yield components were influenced by genetic factors to varying degrees, as reflected in their low, medium, and high heritability estimates. Most yield components exhibited low heritability, except for the seed weight per pod, which showed medium heritability. Lines F9-Lom2/129-34, F9-VR480B/V1-156, and F9-VR10/V1-49 demonstrated superior yield components and high productivity (2.19–2.37 t/ha). These three lines were classified as a resistant to highly resistant classification for pod shattering. The sun-drying method was most effective in revealing the variation in pod-shattering resistance among the tested lines. These findings confirm that genetic variation influences both yield potential and pod shattering resistance in mung bean lines, providing valuable insights for future breeding programs.

Keywords: Mung bean (V. radiata L.), determinate, pod-shattering resistance, selection, variance components, heritability, yield potential

Key findings: The research elucidates the yield potential and pod-shattering resistance of IPB mung bean (V. radiata L.) lines. Pod shattering on mung bean causes significant yield losses before and during harvest in tropical areas. It is valuable to have a simple method for observing pod shatter resistance without relying on laboratory tests.

Inadequate rainfall in the sugarcane-growing regions is a major constraint. This study evaluated 33 diverse sugarcane (Saccharum spp. complex) genotypes for drought tolerance to address this issue. Significant (< 0.05) variances across environments (normal, mild water stress, and rainfed) due to genotypes and environments along with higher heritability (> 60%) and genetic advance (> 20%) for CCS (t ha^-1) and related traits justified strong potential for genetic improvement. Novelty lies in the combined use of “Eberhart and Russell Regression” and “GGE biplot” analyses. The Regression’s model better identified the adaptability of genotype(s), while the GGE biplot effectively characterized the environments for their discriminating power. Traits like number of millable canes (NMC), sucrose (Pol %), total soluble solids (TSS %), relative water content (RWC), membrane stability index (MSI), proline, and superoxide dismutase (SOD), emerged as the key yield contributor, highlighting their utility as selection indices. Significant higher expression of 10 drought-responsive genes (P5CS, SOD, DEH, BADH, IGS, cAPX, LEA, TPS, ProT, and DRP) in F 391/14 (CoPb 19182) and lower expression of four genes (SOD, DRP, ProT, and BADH) in CoJ 64 provided molecular insights into stress tolerance. These findings offer valuable strategies for breeding resilient cultivars.

Keywords: Sugarcane (Saccharum spp. complex), drought tolerance, genotype × environment interactions, stability and adaptability

Key findings: Sugarcane (Saccharum spp. complex) clone F 391/14 (CoPb 19182) exhibited tolerance under drought conditions.

Wheat (Triticum aestivum L.) is an important staple food crop with agronomic significance and a leading crop in terms of area planted and production worldwide. Therefore, its sustainable production is crucial, requiring greater attention due to its increasing global consumption. The following study aimed to assess the genetic potential of the soft wheat F₁-F₂ populations for economic traits obtained through crossing valuable landraces grown in diverse ecological zones of Uzbekistan. Crossing eight wheat genotypes obtained four hybrids that underwent further evaluation along with their parental forms in 2021–2024 at the Chirchik State Pedagogical University, Tashkent, Uzbekistan. Among the parental genotypes, the recorded trait of average maximum spike length resulted in the wheat cultivar Khivit (11.8 ± 0.25 cm), followed by Kzyl-bugday (11.4 ± 0.48 cm) and Tyuya-tish (11.4 ± 0.27 cm). In the investigated F₁ hybrids, the spike length varied from 10.7 to 12.6 cm. However, nonsignificant differences were notable between the ancient local cultivars Tyuya-tish and Khivit for the average number of spikelets per spike. The highest number of spikelets per spike appeared in the cultivar Ak-bashak (18.7 ± 0.44). In F₂ populations, negative transgression was evident, expressed as a shift by 2–3 classes to the left.

Keywords: Wheat (T. aestivum L.) landraces, F₁ and F₂ hybrids, inheritance, genetic variability, coefficient of variation, spike length, spikelets, grains per spike, grain yield

Key findings: Genetic analysis revealed grains per spike were dependent on the genetic potential of the wheat (T. aestivum L.) cultivars. The grains per spike occurred to be transmitted by the negative incomplete dominance. In F₂ populations, for grain weight per spike, the coefficient of variation was twice as high compared with the parental genotypes, indicating medium and high genetic variability.

Maize is the second staple food after rice that supports livestock feed and the rural economies of smallholder farmers. However, the broad agroecological variability causes variations in maize (Zea mays L.) productivity due to genotype-environment interaction (GEI) in Indonesia. Thus, the following study aimed to evaluate the promising maize hybrids with favorable environments using the GGE (genotype + genotype × environment) biplot through GEIs. Seventeen single-cross maize hybrids and two check cultivars (NASA-29 and P-36) underwent evaluation in 2021 through a randomized complete block design (RCBD) with three replications at nine locations in Indonesia. Results revealed significant differences among genotypes, environments, and their interactions (p < 0.01), indicating strong GEI effects. Based on the biplot analysis, West Lombok emerged as the most favorable environment, while Manado was the most unfavorable environment for maize hybrid productivity. Based on the GGE biplot analysis, hybrid ST-201328 demonstrated the highest grain yield and stability, becoming the most recommendable as a promising maize hybrid in Indonesia. These findings underscore the usefulness of the GGE biplot analysis in guiding hybrid selection and targeting suitable test sites for future hybrid maize breeding and development programs.

Keywords: Maize (Z. mays L.), promising hybrids, favorable location, GGE biplot, genotype-by-environment interactions, grain yield

Key findings: According to this study, West Lombok is distinctly the most favorable environment for maize (Z. mays L.) production, while Manado is the most unfavorable. Hybrid ST-201328 demonstrated the highest grain yield and stability and came as the most recommended promising maize hybrid in Indonesia.

This study evaluated the physiological and yield-related responses of 18 advanced upland cotton (Gossypium hirsutum L.) lines and the cultivar Namangan-77 under different water conditions. Significant differences were evident in total water content, transpiration rate, and yield traits across genotypes under optimal and water deficit environments. Lines L-1, L-29, and L-24 demonstrated lower sensitivity to drought stress for physiological and agronomic traits, suggesting their potential in breeding for drought tolerance. Correlation analysis indicated a weak relationship between leaf water content and transpiration rate under optimal water conditions, whereas under water deficit, a positive association appeared between leaf hydration and cotton weight per boll. Furthermore, under prolonged drought, a strong positive correlation between leaf water content and transpiration rate occurred, highlighting the importance of efficient water use. Lines L-2, L-24, and L-11 produced heavier seeds under optimal water supply, although drought significantly reduced seed weight and fiber yield in most genotypes. These findings contribute valuable insights for future cotton breeding programs targeting improved drought resilience and stable productivity.

Keywords: Upland cotton (Gossypium hirsutum L.), water regimes, drought conditions, physiological traits, chlorophyll, carotenoids, morpho-agronomic traits

Key findings: The identification of cotton (G. hirsutum L.) lines L-16 and L-23 was successful, exhibiting stability for transpiration rate in plant leaves under water deficit conditions. Consequently, they are beneficial as breeding material in developing drought-tolerant cotton genotypes. Among medium-fiber cotton lines, lines L-1, L-29, and L-24 showed less sensitivity to water deficit as compared with other lines for physiological and economic traits.

Oxidative stress caused by the accumulation of reactive oxygen species (ROS) produces harmful toxic effects on plant cells and exposes the cotton crop to high temperatures, which are the major limiting factors causing yield losses. Every cotton genotype under heat stress, the pro/antioxidant being a key system among the biochemical factors contributing to plant protection, entailed studies in two cotton cultivars, Surkhan-103 (G. barbadense L.) and Bukhara-102 (G. hirsutum L.) in the laboratory and field conditions. The antioxidant enzyme activities, including superoxide dismutase (SOD), catalase (CAT), peroxidase (PO), malondialdehyde (MDA), and proline, underwent evaluation under prolonged (6-hour) exposure to high temperature (45 °C). The results revealed cultivars Surkhan-103 and Bukhara-102 are classifiable as resistant to heat stress by their biochemical parameters; an increase in the concentrations of hydrogen peroxide and MDA with activities of antioxidant enzymes could become the key markers of plant tolerance and intolerance to heat stress. Under high-temperature conditions, the fine-fiber cultivars Surkhan-104 and Surkhan-103, the medium-fiber cultivars Bukhara-102, S-6577, and S-6585, and the advanced lines L-688, L-214, and L-403 exhibited considerable stability. These heat-tolerant genotypes achieved recommendation for use in future breeding programs aimed at improving stress resilience.

Keywords: G. barbadense and G. hirsutum, hyperthermia, malondialdehyde (MDA), superoxide dismutase (SOD), peroxidase, reactive oxygen species (ROS), proline

Key findings: The study comprising the hyperthermia effect on cotton (G. barbadense and G. hirsutum) cultivars revealed significant insights into plant responses to heat stress. Both cultivars demonstrated resilience by maintaining higher activities of key antioxidant enzymes under prolonged exposure to high temperatures.

A comparative analysis of economically valuable traits of the early-maturing soybean (Glycine max L.) exotic cultivars (K-126, K-127, and K-183) with the local standard cultivar Orzu was the aim of this study. The analysis centered on assessing the soybean genotypes’ adaptability to the soil and climatic conditions of the Tashkent Region, Uzbekistan. The examined key indicators included grain yield, 1000-seed weight, and protein, oil, and cellulose contents. Analysis of variance revealed significant differences among the soybean cultivars, identifying promising directions for breeding. The standard cultivar Orzu demonstrated the highest yield and protein content. The exotic cultivar K-126 stood out for its high oil content, suggesting its potential for vegetable oil production. The exotic cultivar K-183 showed the maximum cellulose content, beneficial for use in the biomaterial and bioenergy production. The results identified the promising soybean genotypes for targeted breeding focused on food, oil production, and industrial bioresource applications.

Keywords: Soybean (G. max L.), early-maturing exotic cultivars, economically valuable traits, grain yield, 1000-seed weight, protein, oil, cellulose content

Key findings: The early-maturing soybean (G. max L.) exotic cultivars revealed significant differences for grain yield, protein, oil, and cellulose content, indicating the highest genotypic variability and adaptability to the Tashkent Region’s conditions. The standard cultivar Orzu showed the highest grain yield and protein content, while the exotic cultivars K-126 and K-183 demonstrated superior oil and cellulose contents, respectively.

The present research aimed to assess the pivotal role of gamma (γ-ray) and fast neutron (FN) radiations in developing rice (Oryza sativa L.) mutant types resistant to salinity (NaCl) and drought stress conditions. Local rice cultivars irradiated with different levels of ionizing radiation had their seeds subjected to salinity and drought stress conditions. Rice cultivars showed varied responses to ionizing radiation and stress factors for morphological and yield-related traits. The highest number of mutant forms resulted from the local rice cultivar Syr Suluy, followed by two other cultivars, viz., Leader and Aikerim. The resulting M1 genotypes significantly differed from the parental forms for morphological and yield-related parameters, i.e., plant height, panicle length, grain size, and grain weight. This genetic material can be effective in the development of synthetic cultivars adapted to the soil and climate stress conditions of the Aral Sea area in Kazakhstan.

Keywords: Rice (O. sativa L.), cultivars, mutation, gamma rays, fast neutrons, salinity and drought stress conditions, morphological and yield-related traits

Key findings: Determining the average lethal irradiation doses was successful for the local rice (O. sativa L.) cultivars that had been bred for the specific environmental conditions of Kazakhstan, as well as establishing their salinity and drought treatment levels. Rice cultivar Aikerim showed a higher productivity than the control. The fast neutron-irradiated seeds produced more surviving rice plants with higher productivity than γ-rays.