Northern corn leaf blight (NCLB) is a serious foliar disease in sweet corn (Zea mays L. var. saccharata) that considerably affects its productivity. This study evaluated the general combining ability (GCA) and specific combining ability (SCA) for NCLB resistance and yield-related traits in sweet corn. The crossing of five inbred lines and two testers using a line-by-tester design produced 10 F₁ hybrids. These F₁ hybrids and two commercial checks underwent evaluation through a randomized complete block design (RCBD) in 2025 at the PT BISI International, Pujon, Indonesia. The results showed Line B had a desirable negative GCA for disease severity and a positive GCA for yield, identifying it as a robust candidate parent for high-yielding and NLCB-resistant hybrids. Disease severity management was mainly with the non-additive gene action and revealed a weaker association between SCA and the hybrid performance, indicating that no single parameter was sufficient to predict hybrid success. Instead, an integrated selection approach is necessary considering the GCA, SCA, and field performance. The hybrid B × G emerges as the best candidate, showing significant resistance to NCLB and higher yield. The selection of parental genotypes based on combining ability and field evaluation could accelerate the development of disease-resistant and high-yielding hybrids.

Keywords: Sweet corn (Z. mays L. var. saccharata), Exserohilum turcicum, additive, dominance, variance components, hybrid performance

Key findings: The results revealed non-additive gene action predominantly influenced NCLB resistance in sweet corn (Z. mays L. var. saccharata). The identification of hybrid B × G succeeded as the best potential to use in developing sweet corn hybrids with NCLB resistance and higher yield.

Accurate heterosis prediction is essential for tomato (Solanum lycopersicum L.) hybrid breeding. This study evaluated heterotic effects and parental genetic distance (GD) using open reading frames (ORF)-targeted sequence-related amplified polymorphism (SRAP) markers, assessing their correlation with agronomic traits. Six parental genotypes’ crossing used a North Carolina II design, with F1 hybrids evaluated in a randomized complete block design. Hybrid H₂ exhibited the highest heterosis for fruit weight, achieving 181% mid-parent heterosis (MPH) and 173.3% best-parent heterosis (BPH). Maximum GD (Nei = 0.183) occurred between P1 and P5. Notably, GD correlated significantly and positively with fruit weight per plant (MPH: r = 0.713; BPH: r = 0.742) but negatively with harvest time (MPH: r = –0.733; BPH: r = –0.742). These findings suggest that SRAP-derived GD is a reliable predictor for fruit weight and harvesting time in tomato breeding.

Keywords: Tomato (S. lycopersicum L.), heterosis, genetic distance, correlation, SRAP, yield-related traits

Key findings: This study indicates that using SRAP-based genetic distance can help choose parents to create tomato (S. lycopersicum L.) hybrid with high productivity and early maturity.

Gamma ray irradiation combined with in vitro Polyethylene Glycol (PEG 6000) selection sought to develop and select mutants with enhance drought tolerance in shallots (Allium ascalonicum L.). The research aimed to identify an effective gamma ray dose in inducing mutation in shallot stem bases of the Bima variety and the ideal PEG concentration to select drought tolerance mutant lines. The seven doses of gamma-ray irradiation (0, 2, 4, 6, 8, 10, and 12 Gy) and four PEG concentrations (0%, 10%, 20%, and 30%) were treatments used. The results showed the LD₅₀ of gamma-ray irradiation was 5.92 Gy, while the LD₅₀ of PEG was 18.57%. The higher the dose of gamma-ray irradiation (> 8 Gy) and PEG (> 20%), the greater the inhibition in the culture’s growth. In selection media with 20% PEG, the lowest relative decrease index (RDI) was visible in surviving shoots derived from 6 Gy, which produced the longest roots. The results suggested the 6 Gy gamma-ray irradiation followed by in vitro selection using 20% PEG could be effective for developing drought-tolerant shallots. Out of 30 mutant plants, six promising lines derived from explants irradiated by 6 Gy, i.e., B6G-1, B6G-3, B6G-4, B6G-5, B6G-9, and KI-1, were able to form greater bulbs per clump and weight per bulb than the control, Bima variety.

Keywords: Shallot (A. ascalonicum L.), drought tolerance, gamma-ray irradiation, PEG 6000, in vitro selection

Key findings: Although research on drought-tolerant shallots (A. ascalonicum L.) remains scarce, this study highlights the application of mutagenesis (gamma irradiation) and in vitro selection (PEG 6000) to enhance shallot drought tolerance. Six promising mutant lines were selected for subsequent evaluation.

This study sought to investigate the genotypic variability in F₁ and F₂ populations and inheritance of key agronomic traits in soybeans (Glycine max L.) derived from diverse parental genotypes. The F₁ hybrids exhibited considerable heterosis and dominance deviations, especially in cross combinations involving parental genotypes Ehtiyoj and To‘maris, which consistently cross several traits. In F₂ populations, transgressive segregation appeared frequently, indicating the presence of wide phenotypic diversity and polygenic inheritance. The highest heritability estimates (h² ≥ 0.91) and trait stability in cross combinations like Ehtiyoj × To‘maris and Nena × Ehtiyoj suggested their suitability as donor genotypes in soybean breeding programs. The coefficient of phenotypic variation (V%) ranged from 4.8% to 55.9%, observing the highest variability in the seed weight. The 1000-grain weight showed moderate to high genetic control. The results underline the importance of parental genotype selection in breeding and support the integration of high-performing hybrids into future improvement strategies of soybeans.

Keywords: Soybean (G. max L.), F₁ hybrids, F₂ populations, heritability, phenotypic variability, transgressive segregation, agronomic traits

Key findings: The soybean (G. max L.) F₂ populations showed wide phenotypic variation and high heritability for key agronomic traits. The populations Ehtiyoj × To‘maris and Nena × Ehtiyoj exhibited considerable inheritance for the seed number and weight, indicating valuable potential for selection and high-yielding soybean breeding programs.

Cotton leafroll dwarf virus (CLRDV) is a significant aphid-transmitted Polerovirus, causing yield loss in cotton globally, leading to symptoms like leaf reddening/rolling, stunting, maroon stems, and bushy tops through asymptomatic infection. CLRDV, which belongs to the family Solemoviridae, is an economically important phytopathogen that causes considerable growth reduction, yield losses, and fiber quality deterioration in cotton. In this study, the CLRDV investigation ensued in cotton samples collected from fields in the Tashkent Region, Uzbekistan. Total RNA extraction came from symptomatic plants, with polymerase chain reaction (PCR) assays performed using specific primers targeting the coat protein (CP) gene of the virus. Several cotton samples reached positive identification for the CLRDV, with the resulting amplicons sequenced to determine the viral nucleotides’ composition. Based on sequence data, the obtained isolate, as deposited in the GenBank database, had the name UZKIB-1. Phylogenetic analysis revealed the UZKIB-1 shared 96.58% nucleotide identity with CLRDV isolates Henan and CN-S5 (China) and Q3514 (Thailand). Eleven key mutations also succeeded in their detection, indicating ongoing evolutionary divergence within regional CLRDV populations. The results confirmed the presence of CLRDV in Uzbekistan, which will contribute to understanding its genetic diversity and epidemiological significance.

Keywords: Cotton leafroll dwarf virus, field surveys, RT-PCR, coat protein gene, phylogenetic analysis, Tashkent Region

Key findings: Cotton leafroll dwarf virus (CLRDV) detection was successful in various cotton samples collected from the Tashkent Region, Uzbekistan, using molecular analysis. The nucleotide sequence of the UZKIB-1 isolate showed 96.58% identity with CLRDV isolates Henan and CN-S5 (China) and Q3514 (Thailand). Phylogenetic analysis and the identification of 11 mutations revealed ongoing genetic divergence within the CLRDV population in Uzbekistan.

Potato (Solanum tuberosum L.) is among the most economically important crops worldwide, yet its productivity acquires severe constraints from viral infections, especially the Potato virus X (PVX). This study aimed to develop an optimized double-antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA) for the rapid and reliable diagnosis of PVX in seed and field materials. Virus propagation in Datura stramonium and D. tatula enabled the preparation of purified antigen and polyclonal antiserum in rabbits. Optimization trials established the most effective dilutions for primary (1:2000) and secondary (1:5000) antibodies, achieving approximately 96% sensitivity and 94%–95% specificity. The improved ELISA demonstrated a strong diagnostic performance, ensuring early detection of PVX in potato cultivars grown under Uzbekistan conditions. The application of the test revealed high infection rates (80%–100%) in certain cultivars, whereas others, including Folva, Piskom, and Aureta, showed no infection, indicating their suitability for virus-free breeding. The developed DAS-ELISA provides a cost-effective, rapid, and reproducible diagnostic platform suitable for seed certification, monitoring, and phytosanitary programs. Its integration with RT-PCR and eco-safe vector management can further enhance potato yield stability and strengthen regional plant health protection systems.

Keywords: Potato (S. tuberosum L.), Potato virus X, ELISA, antigen, isotonic solution, polyclonal antiserum, conjugate

Key findings: Potato (S. tuberosum L.) yields primarily rely on virus-free seeds and recommended crop husbandry. The optimized DAS-ELISA (1:2000/1:5000) achieved ~96% sensitivity and ~94%–95% specificity, enabling PVX detection for seed certification, monitoring, and virus-free programs. Pairing ELISA with RT-PCR and vector control strengthens the phytosanitary protection and stability.

This study employed total RNA extraction, cDNA synthesis, and PCR analysis for molecular characterization of pathogenic viruses infecting stone fruits. Leaf samples of sweet cherry (Prunus avium L.) showing symptoms of viral infection entailed collection from the orchards located in the districts of Bostanliq and Parkent of Tashkent Region, Uzbekistan, with the total RNA subsequently extracted. The quantity and quality of the extracted RNA reached their evaluation, performing cDNA synthesis using high-quality RNA samples. Polymerase chain reaction (PCR) proceeded with virus-specific primers targeting major pathogens of stone fruit crops. These include the Prunus dwarf virus (PDV), Plum pox virus (PPV), Prunus necrotic ringspot virus (PNRSV), Peach rosette mosaic virus (PRMV), Little cherry virus (LCV), Cherry leaf roll virus (CLRV), and Cherry green ring mottle virus (CGRMV). During the examination, the presence of CLRV was successful for validation by PCR in the analyzed stone fruit samples. The obtained results revealed a distinct distribution of CLRV infection and provide a practical basis for the selection of virus-resistant cultivars. The results demonstrate a significant practical value for the selection of virus-resistant stone fruit cultivars. The obtained results highlight the practical relevance of molecular diagnostics for selecting virus-resistant stone fruit cultivars.

Keywords: Sweet cherry (P. avium L.), Cherry leaf roll virus (CLRV), Prunus spp., RNA extraction, cDNA synthesis, PCR, molecular diagnostics

Key findings: Molecular characterization confirmed the cherry leaf roll virus (CLRV) in the studied virus samples of the cherries and stone fruits in Uzbekistan.

Cytogenetic and molecular genetic studies of the cotton haploid describe its morpho-biological features in comparison with the parental genotypes. This research aimed to study the cotton haploid (277₂) spontaneously developed through interspecific crossing of monosomic line Mo15 (Gossypium hirsutum) with Pima 3-79 (G. barbadense) to create the chromosome-substituted cotton lines. With species incompatibility, selective elimination of chromosomes took place in one of the parental genomes observed in interspecific hybrids. The haploid plant displayed characteristics of a thin and tall stem, dense foliage, shortened internodes, small three-lobed leaves, and complete sterility. In the metaphase I of meiosis, 26 univalents manifested random distribution in the pollen mother cells. The haploid stood out by the complete absence of bivalent formation and presence of unpaired chromosomes in the pollen mother cells. Molecular genetic analysis of the haploid using SSR markers revealed the alleles only from the species G. hirsutum in all 26 chromosomes of the haploid genome, which confirmed the selective elimination of chromosomes of the entire paternal genome. The promising results indicated the possibility of using haploid inbreeding by developing doubled haploids (DH).

Keywords: Cotton, Gossypium hirsutum, G. barbadense, monosomic line, haploid, selective elimination of chromosomes, SSR markers

Key findings: Cytogenetic analysis of the interspecific F₁ hybrid (277₂) obtained through crossing of the monosomic line Mo15 (G. hirsutum L.) with disomic line, Pima 3-79 (G. barbadense L.) appeared with morpho-biological features and complete absence of chromosome pairing. The SSR markers confirmed the presence of alleles only from the species G. hirsutum, indicating selective elimination of chromosomes.

Yellow rust (Puccinia striiformis f. sp. tritici) is the primary disease affecting wheat (Triticum aestivum L.) crop productivity worldwide. The latest study aimed to evaluate the 68 wheat cultivars and advanced lines for resistance to yellow rust under field conditions using both morphological assessment and SSR molecular markers. The results revealed eight wheat genotypes (Yr15/6 Avocet S, Xisorak, Yr5/6 Avocet S, Triticum spelta, Yr10/6* Avocet S, Yr SP/6* Avocet S, Spaldings Prolific, and Andijon-2**) were distinctly highly resistant. The two SSR markers Barc008 and Gwm140 proved to be the most reliable for detecting resistance, whereas four other markers (Gwm340, Gwm111, Xgwm131, and Gwm251) showed variable results across the genotypes. The integration of morphological and molecular data highlighted the genetic diversity in yellow rust resistance and demonstrated their potential to efficiently screen the wheat germplasm. The results provide a valuable base for selection of resistant parental lines and employment of marker-assisted selection (MAS) in wheat breeding programs aimed at improving the resistance to yellow rust disease.

Keywords: Wheat (T. aestivum L.), yellow rust, SSR markers, Yr genes, resistance, marker-assisted selection (MAS), genotypes evaluation

Key findings: Eight promising wheat (T. aestivum L.) genotypes (Yr15/6 Avocet S, Xisorak, Yr5/6 Avocet S, Triticum spelta, Yr10/6* Avocet S, Yr SP/6* Avocet S, Spaldings Prolific, and Andijon-2) showed complete resistance to yellow rust under field conditions. The SSR markers Barc008 and Gwm140 were successful as highly reliable for detecting this resistance, demonstrating robust concordance with morphological evaluation.

The study, conducted in a lath house in the autumn of 2022–2023 at the College of Agriculture, Al-Qasim Green University, Al-Qasim, Iraq, determined the humic acid effect on the vegetative growth of the rosemary plant (Rosmarinus officinalis L.). The experiment included two factors: the first factor was pinching, where half of the plants received pinching and the other half was without pinching. The second factor was adding humic acid at concentrations of 0, 4, and 8 ml/L and spraying with kinetin at concentrations of 0.50 and 100 mg/L. The experiment layout was in a randomized complete block design (RCBD) with factorial arrangement (2 × 3 × 3) and three replications. The triple interaction treatment of pinching, humic acid at 0 concentration, and kinetin at 0 concentration gave significant highest values for plant sprouting (29.67 cm). Meanwhile, for the concentration of 50 mg/L, the number of vegetative branches is 5.33 branches plant^-1, and the treatments (P1), humic (8 ml/L), and kinetin (50 mg/L) gave the topmost values, significantly affecting the traits, stem diameter (5.98 mm), and the number of leaves (696.00 leaves plant^-1).

Keywords: Rosemary plant (R. officinalis L.), pinching, humic acid, kinetin, sprouting, branches per plant, stem diameter, number of leaves

Key findings: The triple interaction treatment of pinching P1, humic acid at 0 concentration, and kinetin at 0 concentration significantly gave the highest values for sprouting (29.67 cm). Similarly, the concentration of 50 mg/L resulted in the number of vegetative branches at 5.33 branches per plant in the rosemary plant (R. officinalis L.).