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.

Breeding for fertilizer-efficient rice is paramount. The succeeding research aimed to study the genetic makeup and selection procedure for tolerant rice genotypes in minimum fertilizer. The genetic material comprised 106 F₅ rice lines and five check genotypes grown under optimum and minimum fertilizer conditions. The experiment layout was in an augmented design with five replications. The results indicated genotype-by-environment interactions significantly (p < 0.01) affected rice yield-related traits, specifically productivity. The identified rice lines totaled 26 through multi-trait genotype-ideotype distance index (MGIDI) analysis using 25% selection intensity. The heritability value in the optimal environment (0.725) was higher than in the minimum environment (0.628). Similarly, values for genetic advance (GA) and genetic advance as a percentage of the mean (GAM) in the optimal environment (1.160% and 18.680%) were higher than those in the minimum environment (0.659% and 13.158%). The geometric mean productivity (GMP), harmonic mean (HM), mean productivity (MP), and stress tolerance index (STI) exhibited a significant positive correlation with the average yield under optimum conditions (Yp) and minimum conditions (Ys). However, the stress susceptibility index (SSI) and tolerance index (TOL) showed a negative correlation with Ys, indicating selection based on the tolerance index identified the best lines, G27 and G66.

Keywords: Rice (O. sativa L.), F₅ populations, minimum fertilizer, selection, heritability, genetic gain, tolerance indices, yield-related traits

Key findings: The study highlighted the use of the MGIDI method and tolerance indices (TOL, SSI, STI, MP, HM, and GMP) in identifying promising rice (O. sativa L.) genotypes better suited for low-fertilization conditions. These insights serve as a valuable resource for optimizing fertilizer efficiency to enhance sustainable rice production.

The wheat advanced lines of the F5 generation, obtained through interspecific hybridization (T. durum × T. aestivum), incurred studies for salt tolerance in terms of morphophysiological traits and grain yield under normal and saline soil conditions. The results revealed that salt caused a significant decrease in the photosynthetic pigments, photosystem II activity, and relative water content in the leaves of advanced wheat lines. Overall, the saline stress conditions considerably affected the photosynthetic pigments in most of the advanced lines, while in some genotypes, it was relatively less. Thus, the chlorophyll (a+b), carotenoids, photosystem II activity, and relative water content were more pronounced in the hybrids Leyaqatli-80 × Mirbashir-128, Tale-38 × Kyrmyzy gul-1, Gobustan × Sheki-1, and Mirbashir-50 × Shiraslan-23 than in other hybrids. These hybrids showed greater salt tolerance. On grain yield losses in saline soil, the hybrids Murov × Daghdash, Tale-38 × Kyrmyzy gul-1, Gobustan × Sheki-1, Barakatli-95 × Vugar, Mirbashir-50 × Shiraslan-23, Gobustan × Barakatli-95, Garabagh × Mirbashir-128, and Garabagh × Shark displayed higher resistance. This resistance was for ear weight, the number of grains, and grain weight. In the future, growing these advanced wheat lines under wider saline areas as salt-tolerant cultivars can be successful.

Keywords: Wheat interspecific (T. durum × T. aestivum) advanced lines, saline stress conditions, heterosis, dominance, morphophysiological traits, spike traits, productivity

Key findings: The study identified the promising wheat interspecific (T. durum × T. aestivum) advanced lines for heterotic and dominance effects over better parents for yield-related traits that can help in developing high-yielding wheat genotypes.

The following research comprised the discussion on the spread of the maize dwarf mosaic virus (MDMV), virus transmission, and scientifically based measures to combat the virus. The MDMV monitoring centered on the spread, diagnosis, and impact of the virus on morphophysiological traits and productivity of different maize cultivars. Over the past four years of research, the MDMV infection in corn samples was 44.7% (2020), 35.9% (2021), 27.0% (2022), and 23.0% (2023). The MDMV level of infection declined every year due to comprehensive measures to combat MDMV. In identifying reserve plants and vectors (aphids) of the virus, the main provision aimed at the use of various methods in combating the MDMV. The results revealed Sorghum halepense Pers. was the chief reservoir of MDMV. The complex control measures include selection of cultivars and hybrids resistant to MDMV. Based on the results, determining the corn cultivars emerged from their resistance to the MDMV. The hybrids Legend F1 from France, DKS 4141 F1 from Turkey, and Phenomenon F1 from Switzerland were notable with an average degree of MDMV infection. The degrees of infection were highest in the maize cultivar Mazza from Uzbekistan and the hybrid Megaton F1 from France, which proved not resistant.

Keywords: Maize dwarf mosaic virus (MDMV), maize cultivars and hybrids, virus host and transmission, Sorghum halepense Pers., vectors, morphophysiological traits, productivity

Key findings: For the maize dwarf mosaic virus (MDMV), the Sorghum halepense Pers. was apparently the main reservoir. In complex control measures, the corn cultivars’ identification occurred from their resistance to MDMV.

Cassava tuberous roots are rich in starch but deficient in micronutrients such as provitamin A. The cassava cultivar Carvita-25 is a yellow variant of a white-fleshed cassava genotype (Adira-4) obtained through friable embryogenic callus. The following study aimed to ascertain substantial disparities in metabolite profiles and gene transcripts associated with carotenoid-related characteristics. Genotype Carvita-25 contains β-carotene and its derivative apocarotenoid, responsible for the yellow coloration of the tubers. The metabolite profile exhibited discrepancies in metabolite composition between the cultivars Adira-4 and Carvita-25. Genotype Adira-4 contains the highest levels of amino acid compounds, peptides, and their derivatives, while genotype Carvita-25 contains more amine-type compounds. Differential transcription levels were notable among the genes responsible for carotenoid biosynthesis, Manes.02G081700.1 (PSY1). An enhanced transcription level of PSY1 was evident in Carvita-25 compared with Adira-4, while the lower transcription level of PSY2 resulted in Carvita-25 compared with Adira-4. The GO (gene ontology) and KEGG (Kyoto Encyclopedia of Genes and Genomes) analyses revealed the upregulation of 2,000 genes and downregulation of 1,772 genes in Carvita-25 compared with Adira-4. These comprise cytochrome P450 (CYP82D47), and bHLH family transcription factors were the candidate regulators of carotenoid-related genes in root tubers. This information can be further applicable to developing strategies for improving the quality of cassava plants rich in carotenoid compounds.

Keywords: Cassava genotypes, apocarotenoids, metabolites, phytoene synthase, transcriptome, yellow-fleshed cassava

Key findings: Carvita-25, a mutant cassava, has appeared to contain beta carotene and apocarotenoid metabolites with provitamin-A functions. The discrepancies in phytoene synthase genes and PSY1 and cytochrome 450 (CYP82D47) have been the identified primary factors contributing to variances in the carotenoid profile of Carvita-25 from Adira-4.

Cacao (Theobroma cacao L.) is an important export crop, requiring high-quality beans with sustainable production to meet market demands. For genetic enhancement, controlled hybridization provides a pathway to improving bean quality and increasing genetic variation in cacao. This study evaluated phenotypic variation in 16 quantitative traits of F1 progeny derived from four cross combinations and performed molecular characterization using 11 polymorphic markers. Data collection progressed in 2019–2021. Notably, the F1 hybrid TSH858 x DR1 emerged as promising by showing higher average pod weight and favorable bean counts per 100 g, aligning with AA/A quality grades. The F1 hybrid 5-1 (2) showcased the highest single dried bean weight and lowest pod index, indicating large bean sizes. Molecular characterization revealed the highest observed (0.64) and expected (0.56) heterozygosity, confirming the origins of hybrids. The average polymorphism information content (PIC) was 0.50, suitable for genetic studies. Distinct genetic relationships among the F1 progenies suggested that bean yield and quality variations stem from genetic variation. The results highlighted that strategic hybridization played a vital role in boosting genetic diversity and bean quality as key goals in cacao breeding programs.

Keywords: Cacao (T. cacao L.) breeding, bean quality, controlled hybridization, genetic variation, molecular characterization, heterozygosity, genetic relationship

Key findings: This study integrates morphological, agronomic, and molecular data to comprehensively evaluate the cacao (T. cacao L.) F1 hybrids. The combined use of phenotypic traits and molecular characterization strengthens the selection strategies for breeding. Emphasis on pod index, yield traits, and quality standards aligns the findings with practical breeding goals and industry needs.