Alternaria brassicicola is a major necrotrophic pathogen causing black leaf spot in cabbage and other cruciferous crops. This study aimed to characterize 19 pathogenic isolates of Alternaria spp. collected from three cabbage-growing regions in Egypt based on morphology, pathogenicity and genetic diversity. Molecular identification based on ITS sequence clustered the collected isolates along with A. brassicicola confirming their identity. Deep morphological analysis delineated the variations in conidial size and septation among the isolates. Pathogenicity test was performed on detached and attached leaves, showing wide variations in lesion size and disease severity among isolates. Genetic diversity analysis used five ISSR primers, generating 46 bands with 72.61% polymorphism. Cluster analysis grouped the isolates into two main clusters, although no clear correlation appeared between genetic patterns, geographic origin, or virulence. Antifungal in vitro assays showed differential sensitivity to difenoconazole, azoxystrobin, mancozeb, and copper oxychloride, with difenoconazole being the most effective at the recommended doses per each. The combined variation in morphology, virulence, genetic sequences, and fungicide sensitivity suggests high adaptive potential in local A. brassicicola population. These findings highlight the need for integrated disease management using diverse resistance sources and fungicide rotation strategies for sustainable control

Keywords: Alternaria brassicicola, genetic characterization, leaf spot disease, ITS sequencing, molecular markers, disease severity assessment, cluster analysis, resistance breeding

Key findings: High genetic, pathogenic, and fungicide-response variability among Alternaria brassicicola isolates underscores their capacity for rapid adaptation in cabbage fields. Accordingly, resistance-breeding programs should pyramid multiple resistance sources and screen candidate cultivars against a broad, representative panel of isolates to secure durable, wide-spectrum control of the leaf-spot disease.

Maize is one of the major crops in Indonesia; however, its national production remains fluctuating. The development of high-yielding hybrid maize cultivars with tolerance to low nitrogen is a vital aim to boost the production. The following research aimed to study the heterotic effects in 10 maize F1 half-diallel hybrids, evaluated under two nitrogen levels, to identify the high-yielding hybrids. The experiment layout had a split-plot design with two factors. The main plots received the nitrogen (N) levels (N1: 50% and N2: 100%), while the 10 F1 hybrids, five parental genotypes, and two check genotypes (NASA-29 and Pertiwi-3) entailed placement in the subplots. Calculating the analysis of variance and heterotic effects occurred for growth, ear, kernel, yield, and flowering traits, followed by heatmap and principal component analyses (PCA). The analysis of variance revealed significant interactions of nitrogen levels and maize genotypes for several traits. Heterotic effects were evident across nitrogen levels for all traits. Heatmap and PCA assisted in identifying the heterosis patterns. Overall, the maize hybrid H₉ (P3 × P5) excelled all other hybrids for most assessed traits, indicating better adaptability to low-nitrogen environments for use in the next breeding program.

Keywords: Growth and yield traits, half-diallel hybrids, heatmap analyses, heterosis, maize, nitrogen stress tolerance, principal component analysis

Key findings: The F1 hybrids revealed heterotic effects for studied traits in maize (Z. mays L.) (up to 21% in growth, 48% in ear, 66% in kernel, and -28% in flowering traits). Nitrogen-by-genotype interactions were considerable across all traits, indicating better adoption to low nitrogen stress. The F1 hybrid H₉ (P3 × P5) was superior for almost all traits for further breeding programs’ use. The heatmap analysis and PCA were notably useful in identifying heterosis patterns and potential hybrids.

Salinity stress is a major constraint in the upland cotton (Gossypium hirsutum L.) productivity, particularly at the seedling stage, where ion toxicity, osmotic imbalance, and oxidative damage severely impair early growth. This study dissected salt tolerance mechanisms across 20 diverse cotton genotypes subjected to three salinity stress levels: control (1.6 dS/m), moderate (12 dS/m), and severe (17 dS/m). Plants, evaluated at the fourth true leaf stage, had their key morphophysiological and biochemical parameters checked. Elevated salinity significantly reduced shoot and root biomass, while sodium accumulation and Na⁺/K⁺ ratios sharply increased, indicating disrupted ionic homeostasis. For plants to cope with this stress, antioxidant enzyme activities—superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT)—markedly rose, reflecting activation of ROS detoxification pathways. The principal component analysis (PCA) differentiated tolerant and sensitive genotypes by integrating multiple traits. CIM-595, Mubarak, CIM-612, and FH-152 were distinct as tolerant genotypes with balanced ionic profiles and elevated antioxidant responses, whereas sensitive lines, such as SB-149, KZ-181, and AGC-999, performed poorly under severe salinity. These findings provide mechanistic insight into cotton’s adaptive strategies and offer robust targets for breeding programs in saline-prone agroecosystems.

Keywords: Cotton (G. hirsutum L.), salinity, seedling stage, salt tolerance, PCA, morphophysiological and biochemical traits

Key findings: This study identified salt-tolerant cotton (G. hirsutum L.) genotypes through principal component analysis, which identified CIM-595, Mubarak, CIM-612, and FH-152 as salt-tolerant genotypes. These lines maintained balanced Na⁺/K⁺ ratios and elevated antioxidant enzyme activities, indicating effective ionic regulation and oxidative stress mitigation. Their performance under high salinity supports their use in breeding salt-resilient cotton.

Heat stress during the reproductive stage, especially during flowering, can considerably diminish grain yield of rice (Oryza sativa L.). A meta-QTL analysis provides a powerful and stable approach to identify QTLs, regardless of the genetic background of the mapping population and the environmental conditions. In the presented research, 95 previously published QTLs underwent MQTL analysis, recognizing 37 most consistent MQTLs across the different genetic backgrounds and panels. The 30 MQTLs identified had narrow confidence intervals (<5 cM), with 20 having attributed over 10% of phenotypic variance, ranging from 2.4% to 40.55%. In 37 MQTLs, 10 main candidate genes representing 10 gene families were successful for selection based on high R² values. Two genes, LOC_Os02g04710 (OsOSC2) and LOC_Os06g05550 (OsGELP74), distinctly appeared with elevated transcript levels in the panicle tissue. The haplotype analysis revealed two rare haplotypes (H017 and H018) for OsOSC2, distinguishing indica and japonica. At the same time, OsGELP74 was evident across several accessions, with only one rare haplotype (H006) representing indica, tropical japonica, temperate japonica, and admixed accessions. The identification of such novel haplotypes associated with key heat-stress-related traits can help accelerate the development of heat-stress-tolerant rice genotypes in Vietnam.

Keywords: Rice (O. sativa L.), accessions, 3K RG, haplotype analysis, MQTL, rice heat tolerance, genetic backgrounds, phenotypic variance

Key findings: In rice (O. sativa L.), heat stress at the flowering stage severely reduces the grain yield, demanding targeted breeding for stable and heat-tolerant germplasm. Meta-QTL analysis identified the key genes and validated haplotype-based breeding for the development of heat-stress-tolerant rice genotypes in Vietnam.

In mung bean (Vigna radiata L. Wilczek), flooding is a major abiotic constraint limiting productivity in flood-prone areas. The presented study aimed to evaluate the morpho-agronomic traits of 15 mung bean genotypes under waterlogging for zero, seven, and 10 days in a randomized complete design with factorial arrangement and three replications. Analysis of variance revealed significant effects of genotypes, flooding durations, and their interactions on the pod number, seed weight, trifoliate leaves, and root traits. After seven days of flooding, genotypes Murai and Lokal Majenang produced the highest pod number (10.33 and 7.00 pods, respectively), while genotypes Kasu and Kutilang produced the fewest pods (5.33 and 8.00 pods, respectively) after 10 days of flooding. Root traits were highly sensitive, particularly with genotypes Kasu and Kutilang expressing better root length (14.1 and 18.0 cm, respectively) and root weight (1.9 and 2.6 g, respectively) under flooding stress conditions. Broad-sense heritability was moderate for root length (31.7%) and wet root weight (22.0%), whereas seed and stover traits showed low heritability. Pod number and root length emerged as key indicators of flooding tolerance. Genotypes Kasu, Lokal Majenang, and Kutilang were the recommended promising donors for breeding waterlogging-tolerant mung beans.

Keywords: Mung bean (V. radiata L.), flooding stress, heritability, landraces, yield traits

Key findings: Flooding stress conditions significantly affected and reduced the growth and yield traits in mung bean (V. radiata L.), and the accessions showed different responses, revealing considerable genetic variability. Pod number and root length surfaced to be the most sensitive and reliable traits for screening tolerance in mung beans.

Robusta (Coffea arabica L.) and Arabica (Coffea canephora A. Froehner) are the major agricultural commodities in Central Sulawesi, Indonesia, known for their unique flavor mostly influenced by local microclimates. The following study aimed to analyze the genetic diversity of 12 coffee genotypes procured from the Central Sulawesi Region using RAPD markers. Ten RAPD primers (OPA01, OPA02, OPA07, OPA16, OPD08, OPA13, OPG03, OPI07, OPY10, and OPX20) generated 103 DNA bands, with 102 as polymorphic. The DNA profiles’ binary data underwent analysis using Jaccard similarity coefficients and the unweighted pair group method with arithmetic mean (UPGMA) clustering. Genetic similarity ranged from 7% to 72%, with an average of 31%. Cluster analysis grouped the coffee genotypes into two main clusters unrelated to their taxonomic classifications, implying extensive genetic divergence potentially driven by local environmental conditions. Four non-conventional primers (OPA02, OPA13, OPA16, and OPD08) successfully amplified the DNA in several local genotypes. However, the local genotype Robusta Dombu did not amplify with any primer, pointing to possible mutation, highlighting its distinct genetic makeup. The results demonstrated a significant genetic diversity among the local coffee genotypes. Robusta Dombu, being a local coffee genotype, emerges as a potential candidate for developing climate-resilient and high-quality cultivars.

Keywords: Arabica, biodiversity, Coffea arabica, Coffea canephora, local adaptation, RAPD, Robusta

Key findings: The study showed the high genetic diversity in Coffea spp. genotypes by using RAPD markers. The phylogenetic clusters have not shown their belonging to two main ancestors, Robusta and Arabica, suggesting their highest variability during adaptation to local conditions.

This latest study aimed to evaluate the triticale cultivars for drought tolerance through morphophysiological traits and molecular analyses. Under artificial drought conditions induced by the polyethylene glycol (PEG-6000), the triticale cultivars Sergiy, Xlebarob, and K. Prag exhibited the highest tolerance and demonstrated better adaptability to drought stress conditions. Molecular analysis identified the alleles (Xgwm484, Xmc525, and Xgwmc389) associated with drought tolerance based on DNA markers, establishing these markers as reliable indicators for selection. Specifically, alleles with 255 bp (Xgwm484), 230 bp (Xmc525), and 260 bp (Xgwmc389) were indicative of drought tolerance, confirming the highest drought tolerance in the cultivars K. Prag, Sergiy, and Xlebarob. These cultivars showed potential for future breeding using molecular techniques like gene pyramiding to enhance drought resistance and are suitable as elite initial material for the selection process. The phylogenetic analysis revealed genetic similarities and differences among the triticale cultivars, highlighting the crucial role of drought tolerance-related markers in selection and ensuring sustainable productivity. The results provided fundamental insights for determining the drought tolerance levels among triticale cultivars and defining future selection directions.

Keywords: Triticale cultivars, drought stress tolerance, PEG-6000, morphophysiological traits, DNA markers, phylogenetic analysis, productivity

Key findings: The study identified drought-tolerant alleles in triticale cultivars using markers Xgwm484, Xmc525, and Xgwmc389. The allele Xgwm484 with 255 bp appeared in cultivars Sardor, K. Prag, Sergiy, and Xlebarob, while the allele Xmc525 with 230 bp was evident in triticale cultivars Tixon, Kunak, Yarillo, K. Prag, Sergiy, Xlebarob, and Prao-02, confirming their highest drought tolerance.

The estimation of genetic parameters of the kenaf (Hibiscus cannabinus L.) plant resistance against root-knot nematodes (M. incognita) using full diallel cross analysis was the aim of this study. Seven H. cannabinus parental genotypes, KR-1, KR-4, KR-5, KR-6, KR-15, Kenafindo-2 (Kin-2), and DS-028, as well as their complete diallel F₁ hybrids, were samples used in the study. The experiment commenced by infecting kenaf plants aged 15 days after sowing (DAS) with M. incognita nematodes in a population of 40 second-stage juveniles/100 g soil. The resistance variables comprised the number of root-knot nematodes, reproductive factors, the number of second-stage juveniles, the total egg mass, and the average number of eggs per mass. The results showed no significant epistatic interaction between genes in determining H. cannabinus resistance against M. incognita. Moreover, the effect of the additive genetic variances was greater than the dominance genetic variances. The kenaf resistance against root-knot nematode revealed the primary control of a partially dominant-additive gene. Dominant genes proved more prevalent than recessive genes in the parental genotypes. Both broad- and narrow-sense heritability values emerged as high.

Keywords: Kenaf (H. cannabinus L.), root-knot nematodes (M. incognita), Hayman’s diallel analysis, genetic parameters, additive and dominance genetic variances, heritability

Key findings: The kenaf (H. cannabinus L.) resistance against root-knot nematode showed the control of a partially dominant gene. Dominant genes appeared more abundant than recessive ones in the parental genotypes. Both broad- and narrow-sense heritability values were high.

Pepper (Capsicum annuum L.) is a vital food commodity, and its shelf life plays a crucial role in determining economic viability. Ethylene, a key regulator in the ripening of climacteric fruits, such as peppers, considerably affects postharvest longevity. The ethylene biosynthesis pathway incurs management from gene families encoding 1-aminocyclopropane-1-carboxylate synthase (ACS) and 1-aminocyclopropane-1-carboxylate oxidase (ACO). The following study investigated the expression patterns of the ACS gene (CaACS6) and the ACO gene (CaACO1), along with a housekeeping gene (CaGAPDH), in three pepper cultivars (Cherry, Anaheim, and Bohemian), using quantitative polymerase chain reaction (qPCR). Gene expression assessment progressed across three maturity developmental stages (young green, large green, and ripening) to elucidate their influence on ethylene synthesis and pepper shelf life. The expression of the CaACS6 gene showed a positive correlation with the ripening stage across all cultivars. In the Cherry cultivar, the expression of gene CaACO1 significantly decreased at the ripening stage, indicating reduced ethylene production and potential for extended shelf life. Similarly, the Anaheim cultivar exhibited a decrease in the expression of both genes (CaACS6 and CaACO1) during the ripening stage, revealing a reduced ethylene production, suggesting a potential for reduced ethylene production and extended shelf life. These insights provide valuable guidance for selecting pepper cultivars with prolonged shelf life, thereby enhancing postharvest quality and commercial sustainability.

Keywords: Pepper (C. annuum L.), cultivars, CaACS6 and CaACO1, gene expression, ethylene production regulatory genes, maturity stages

Key findings: In pepper (C. annuum L.) cultivars, the gene CaACS6 expression with an increased ethylene biosynthesis at the ripening stage, confirmed its role in maturation. Reduced gene CaACO1 expression in pepper cultivars (Cherry and Anaheim) at the ripening stage suggested lower ethylene production, supporting their potential for extended shelf life.

Kasturi tobacco (Nicotiana tabacum L.) is a sun-cured aromatic cultivar prized for its unique flavor and economic potential in premium blends. However, in Indonesia its cultivation constraints come from genetic degradation and susceptibility to various diseases, such as Phytophthora nicotianae, Ralstonia solanacearum, and Cucumber Mosaic Virus (CMV). This study sought to develop high-yielding, disease-resistant, and quality-consistent Kasturi genotypes through the integration of cytoplasmic male sterility (CMS)-based hybridization and recurrent bulk selection. Nine elite genotypes and two check cultivars entailed evaluation during 2020–2022 across three agroecological zones in Jember Regency, Indonesia. The tobacco genotypes Dark CK, Dark BK, and Dark AK exhibited considerable improvement in cured leaf yield (2.037 t ha^-1), cured leaf quality index (78.90), and crop index (151.68). Most tobacco genotypes enunciated remarkable resistance to P. nicotianae and R. solanacearum, though CMV susceptibility remains a challenge. Stability analysis identified four genotypes with consistent performance through genotype-by-environment interaction across diverse environments. The results provide considerable genetic basis and support for the development of export-oriented Kasturi cultivars and contribute to reducing dependency on tobacco imports in Indonesia.

Keywords: Kasturi tobacco (N. tabacum L.), recurrent selection, hybridization, genotype-by-environment interaction, disease resistance, cured leaf quality, yield stability

Key findings: The integration of CMS-based hybridization and recurrent selection successfully produced Kasturi tobacco (N. tabacum L.) genotypes with superior yield, better leaf quality, and disease resistance. Four tobacco genotypes revealed broad environmental adaptability, while one genotype showed specific adaptation. These genetic resources will enhance the productivity and export potential of sun-cured aromatic tobacco.