Search Results (2,193)

Wild potato relatives are vital for breeding programs to tackle rising temperatures. This study proposes a methodological approach based on the examination of genetic variation among 19 accessions belonging to Solanum chacoense and Solanum commersonii from the Embrapa Potato Genebank under heat stress (HS). Heat tolerance coefficient (HTC) was calculated using genotypic values predicted through mixed models. After 15 days of heat stress (DHS), a significant variation in gas exchange and chlorophyll fluorescence indicates strong breeding potential and photosystem resilience. By 35 DHS, increased pigment variation suggests acclimation. Based on predicted genotypic values, S. chacoense outperforms S. commersonii in tuber production and gas exchange under HS, and principal component analysis (PCA) performed using the HTC shows early resistance driven by photosynthesis, mid-term by tuber yield, and long-term by gas exchange and tuber production. Genotypes BRA00167017-3, BRA00167023-1, BRA00167025-6, and BRA00167028-0 excel in heat comprehensive evaluation values (HCEVs)/comprehensive principal component value (F) rankings, demonstrating robust photosynthesis, thermoregulation, and tuber yield. Cluster analysis identifies these as highly tolerant, ideal for breeding heat-resilient potatoes. These PCA-derived weights and genotype clustering system provide a precise tool for selecting heat-tolerant wild potato germplasm, categorizing them into highly tolerant, moderately tolerant, sensitive with late recovery, and highly sensitive groups acquired for specific objectives of the breeding programs to climate change. Full article

This study examines the impacts of climate change on fisheries and aquaculture in Bangladesh, one of the most climate-vulnerable countries in the world. The fisheries and aquaculture sectors contribute significantly to the national GDP and support the livelihoods of 12% of the total population. Using a Critical Literature Review (CLR) approach, peer-reviewed articles, government reports, and official datasets published between 2006 and 2025 were reviewed across databases such as Scopus, Web of Science, FAO, and the Bangladesh Department of Fisheries (DoF). The analysis identifies major climate drivers, including rising temperature, erratic rainfall, salinity intrusion, sea-level rise, floods, droughts, cyclones, and extreme events, and reviews their differentiated impacts on key components of the sector: inland capture fisheries, marine fisheries, and aquaculture systems. For inland capture fisheries, the review highlights habitat degradation, biodiversity loss, and disrupted fish migration and breeding cycles. In aquaculture, particularly in coastal systems, this study reviews the challenges posed by disease outbreaks, water quality deterioration, and disruptions in seed supply, affecting species such as carp, tilapia, pangasius, and shrimp. Coastal aquaculture is also particularly vulnerable to cyclones, tidal surges, and saline water intrusion, with documented economic losses from events such as Cyclones Yaas, Bulbul, Amphan, and Remal. The study synthesizes key findings related to climate-resilient aquaculture practices, monitoring frameworks, ecosystem-based approaches, and community-based adaptation strategies. It underscores the need for targeted interventions, especially in coastal areas facing increasing salinity levels and frequent storms. This study calls for collective action through policy interventions, research and development, and the promotion of climate-smart technologies to enhance resilience and sustain fisheries and aquaculture in the context of a rapidly changing climate. Full article

Polyploidization is a rapid breeding strategy for producing new varieties with superior agronomic traits. Kenaf (Hibiscus cannabinus L.), an important fiber crop, exhibits high adaptability to diverse stress conditions. However, comprehensive studies on polyploid induction, screening, and genetic identification in kenaf remain unreported. This study first established an optimal tetraploid induction system for diploid kenaf seeds using colchicine. The results showed that a 4-h treatment with 0.3% colchicine yielded the highest tetraploid induction rate of 37.59%. Compared with diploids, tetraploid plants displayed distinct phenotypic and physiological characteristics: dwarfism with shortened internodal distance, increased stem thickness, larger and thicker leaves with deeper green color and serration, as well as enlarged flowers, capsules, and seeds. Physiologically, tetraploid leaves featured increased chloroplast numbers in guard cells, reduced stomatal density, and larger pollen grains, elevated chlorophyll content. Further analyses revealed that tetraploid kenaf had elevated contents of various trace elements, enhanced photosynthetic efficiency, prolonged growth duration, and superior agronomic traits with higher biomass (54.54% higher fresh weight, 79.17% higher dry weight). These findings confirm the effectiveness of colchicine-induced polyploidization in kenaf, and the obtained tetraploid germplasm provides valuable resources for accelerating the breeding of elite kenaf varieties with improved yield and quality. Full article

Structural variation (SV) serves as a fundamental driver of phenotypic diversity and environmental adaptation in plants and animals, significantly influencing key agronomic traits in crops. Common wheat (Triticum aestivum L.), an allohexaploid species, harbors extensive chromosomal SVs and distant hybridization-induced recombination events that provide critical resources for genetic improvement. This study utilizes non-denaturing fluorescence in situ hybridization (ND-FISH) and oligonucleotide multiplex probe-based FISH (ONPM-FISH) to analyze the karyotypes of 153 BC₁F₄–BC₁F₆ lines derived from the hybrid line Xiaoyan 7430 and common wheat Yannong 1212. The results revealed that Xiaoyan 7430 carries 8 alien chromosome pairs and 20 wheat chromosome pairs (lacking 6B), and Yannong 1212 contains 21 pairs of wheat chromosomes. The parental lines exhibited presence/absence variations (PAVs) on chromosomes 2A, 6A, 5B, 1D, and 2D. Chromosomal variations, including numerical chromosomal variation (NCV), structural chromosomal variation (SCV), and complex chromosomal variation (CCV), were detected in the progeny lines through ONPM-FISH analysis. The tracking of alien chromosomes over three consecutive generations revealed a significant decrease in transmission frequency, declining from 61.82% in BC₁F₄ to 26.83% in BC₁F₆. Telosomes were also lost during transmission, declining from 21.82% in BC₁F₄ to 9.76% in BC₁F₆. Alien chromosome 1J^S, 4J, and 6J exhibited the highest transmission stability and were detected across all three generations. Association analysis showed that YN-PAV.2A significantly affected the length/width ratio (LWR) and grain diameter (GD); YN-PAV.6A, XY-PAV.6A, and PAV.5B increased six grain traits (+2.25%~15.36%); YN-PAV.1D negatively affected grain length (GL) and grain circumference (GC); and XY-PAV.2D exerted positive effects on thousand-grain weight (TGW). Alien chromosomes differentially modulated grain characteristics: 1J^S and 6J both reduced grain length and grain circumference; 1J^S increased LWR; and 4J negatively impacted TGW, grain width (GW), GD, and grain area (GA). Meanwhile, increasing alien chromosome numbers correlated with progressively stronger negative effects on grain traits. These findings elucidate the genetic mechanisms underlying wheat chromosomal variations induced by distant hybridization and their impact on wheat grain traits, and provide critical intermediate materials for genome design breeding and marker-assisted selection in wheat improvement. Full article

Universal Stress Protein (USP) plays crucial roles in plant stress adaptation, yet their evolutionary dynamics, regulatory mechanisms, and functional diversification in rice (Oryza sativa) remain poorly understood. This study aimed to conduct a genome-wide identification and characterization of the OsUSP gene family to elucidate its role in abiotic stress responses using integrated bioinformatics approaches. Here, we identified 46 OsUSP genes that are unevenly distributed across 11 rice chromosomes and exhibit significant divergence in protein length, molecular weight, and subcellular localization. Phylogenetic analysis classified OsUSPs into three subfamilies, with conserved motif and domain architectures within groups but distinct structural variations across subfamilies. Evolutionary analysis revealed strong collinearity between rice and other monocots, which suggests functional conservation in grasses, whereas limited synteny with dicots indicates lineage-specific divergence. Cis-regulatory element analysis showed enrichment in ABA, MeJA, drought, and hypoxia response motifs, implicating OsUSPs in hormonal and stress signaling. Expression profiling indicated tissue-specific patterns, with subfamily III genes broadly expressed, while subfamily II members were anther-enriched. Stress response profiling revealed that 24 OsUSPs were significantly induced, while LOC_Os02g54590 and LOC_Os05g37970 emerged as particularly notable due to their broad-spectrum responsiveness, being upregulated under all tested stress conditions. Protein–protein interaction (PPI) analysis indicated that OsUSP proteins potentially interact with Leo1/TPR-domain proteins and are involved in stress response and phosphorylation signaling pathways. This study yields key insights into OsUSP-mediated stress adaptation in rice and pinpoints promising candidate genes to facilitate the breeding of climate-resilient rice. Full article

Ilex verticillata (winterberry) is a valuable ornamental shrub increasingly threatened by leaf blight, a disease that compromises its aesthetic and economic value. While fungal pathogens like Alternaria alternata are known to cause leaf blight in horticultural crops, their role in I. verticillata and the host’s defense mechanisms have not been fully characterized. Our study investigated the pathogen-host interaction by identifying the causal agent and examining the physiological and molecular defense mechanisms of I. verticillata. Through morphological and multi-locus molecular analyses (ITS, TEF1-α, G3PDH, RPB2), A. alternata was confirmed as the primary pathogen, fulfilling Koch’s postulates. Pathogenicity assays revealed distinct disease progression stages, from necrotic lesions to tissue degradation. Transcriptomic profiling uncovered dynamic host responses, with early upregulation of pattern recognition receptors (PRRs) and transcripts encoding antioxidant enzymes (SOD, CAT), followed by downregulation of metabolic pathway genes. Phytohormone analysis highlighted intricate crosstalk, with salicylic acid (SA) peaking during mid-infection and jasmonic acid (JA) rebounding later, reflecting a coordinated defense strategy. Additionally, the oxidative stress marker malondialdehyde (MDA), an indicator of membrane lipid peroxidation, surged early, indicating membrane damage, while sustained induction of antioxidant enzymes suggested adaptive responses. The key finding was distinct phytohormone crosstalk, characterized by a mid-infection SA peak followed by a late JA rebound, alongside an early oxidative burst marked by MDA accumulation and sustained antioxidant enzyme activity. These findings provide a framework for understanding I. verticillata’s defense mechanisms and offer insights for developing targeted disease management strategies, such as resistant cultivar breeding or hormone-mediated interventions. Full article

Guava (Psidium guajava L.), a perennial species native to tropical regions of the Americas, holds significant economic value and plays an important role in the global fruit industry. Although several reference genomes have been published, population-level genomic studies remain limited, hindering genetic improvement efforts. In this study, we conducted whole genome re-sequencing of 62 guava accessions, primarily from Southern China and Brazil. A total of 4,887,006 high-quality SNPs and 731,469 InDels were identified for population genomic analyses. Phylogenetic and population structure analyses revealed subgroupings that largely corresponded to geographic origins. The data indicated that extensive hybridization between accessions from Brazil and or within China has contributed to the development of many dominant commercial varieties. Genetic diversity analyses showed that Brazilian accessions exhibited higher nucleotide diversity and more rapid linkage disequilibrium decay than those from China. Environmental factors and artificial selection likely imposed selective pressures that shaped guava’s adaptability and agronomic traits. A preliminary genome-wide association study (GWAS) identified PgMYB4 as a candidate gene potentially associated with fruit flesh color. These findings provide novel insights into the genetic diversity, population history, and domestication of guava, and lay a valuable foundation for future breeding and improvement strategies. Full article

Dioscorea polystachya (Chinese yam) is a crop valued for both medicinal and edible purposes, and exhibits rich genetic diversity. However, research into its germplasm resources remains understudied, and molecular breeding efforts lag behind. To bridge this gap, this study employed an integrated approach, combining the analysis of 23 phenotypic traits (17 qualitative and 6 quantitative) with genotyping using 19 polymorphic SSR markers. This combined strategy was applied to 53 accessions collected across 16 Chinese provinces to assess genetic diversity, population structure, and marker–trait associations. Phenotypic analysis revealed high diversity, with the Shannon diversity index (I) ranging from 0.09 to 1.15 for qualitative traits and from 1.45 to 1.79 for quantitative traits. Tuber traits exhibited the highest variability (with a CV up to 71.45%), indicating significant potential for yield improvement. Principal component analysis distilled phenotypic variation into eight principal components (accounting for 73.13% of the cumulative variance), and elite germplasm (e.g., DP24, DP52) was selected for breeding based on this analysis. Stepwise regression prioritized eight core evaluation traits (e.g., flowering rate, tuber length). SSR markers amplified 80 alleles (mean 4.211/locus), showing moderate genetic diversity (He = 0.529, PIC = 0.585). Population structure analysis divided accessions into two subpopulations, correlated with geographic origins: Group 1 (northern/southwestern China) and Group 2 (central/eastern China), reflecting adaptation to local climates and human selection. Association analysis identified 10 SSR loci significantly linked (p < 0.01) to key traits, including YM07_2 (flowering, R² = 13.94%), YM37_2 (leaf margin color, R² = 19.03%), and YM19_3 (leaf width, R² = 19.34%). This study establishes a comprehensive genetic framework for Chinese yam, offering molecular tools for marker-assisted breeding and strategies to conserve high-diversity germplasm, thereby enhancing the utilization of this orphan crop. Full article

Cold stress significantly impairs plant growth and development, making the study of cold resistance mechanisms a critical research focus. Oreorchis patens (Lindl.) exhibits strong cold hardiness, yet its molecular and physiological adaptations to cold stress remain unclear. This study utilized microscopy, physiological assays, and RNA sequencing to comprehensively investigate O. patens’s responses to cold stress. The results reveal that cold stress altered leaf anatomy, leading to irregular mesophyll cells, deformed chloroplasts, and variable epidermal thickness. Physiologically, SOD and POD activities peaked at 5 °C/−10 °C, while CAT activity declined; osmotic regulators (soluble sugars, proline) increased with decreasing temperatures. Compared to the reference plants (e.g., Erigeron canadensis, Allium fistulosum), O. patens exhibited lower SOD and POD but markedly higher CAT activities, alongside reduced MDA, soluble sugars, proline, and proteins, underscoring its distinctive tolerance strategy. Low temperature stress (≤10 °C/5 °C) significantly decreased the SPAD index; the net photosynthetic rate (Pn) initially increased and then approached zero within the temperature range from 30 °C/25 °C to 25 °C/20 °C; transpiration rate (Tr) and stomatal conductance (Gs) changed synchronously, accompanied by an increase in intercellular CO₂ concentration (Ci). RNA sequencing identified 1139 cold-responsive differentially expressed genes, which were primarily enriched in flavonoid/lignin biosynthesis, jasmonic acid synthesis, and ROS scavenging pathways. qRT-PCR analysis revealed the role of secondary metabolites in O. patens response to cold stress. This study was the first to discuss the physiological, biochemical, and molecular regulatory mechanisms of O. patens resistance to cold stress, which provides foundational insights into its overwintering mechanisms and informs breeding strategies for cold-hardy horticultural crops in northern China. Full article

Background/Objectives: Paspalum nicorae Parodi is a native subtropical grass species with promising agronomic attributes, such as persistence, drought and cold tolerance, and rapid establishment. However, the species remains underutilized in breeding programs due to the absence of well-characterized germplasm and limited studies on its genetic variability and agronomic potential. This study aimed to estimate genetic parameters, predict genotypic values, and identify superior ecotypes with desirable forage traits, integrating stability and adaptability analyses. Methods: A total of 84 ecotypes were evaluated over three consecutive years for twelve morphological and forage-related traits. Genetic parameters, genotypic values, and selection gains were estimated using mixed models (REML/BLUP). Stability was assessed through harmonic means of genotypic performance, and the multi-trait genotype–ideotype distance index (MGIDI) was applied to identify ecotypes with balanced performance across traits. Results: Substantial genetic variability was detected for most traits, particularly those related to biomass accumulation, such as total dry matter, the number of tillers, fresh matter, and leaf dry matter. These traits exhibited medium to high heritability and strong potential for selection. Ecotype N3.10 consistently showed superior performance across productivity traits while other ecotypes, such as N4.14 and N1.09, stood out for quality-related attributes and cold tolerance, respectively. The application of the MGIDI index enabled the identification of 17 ecotypes with balanced multi-trait performance, supporting the simultaneous selection for productivity, quality, and adaptability. Comparisons with P. notatum suggest that P. nicorae harbors competitive genetic potential, despite its lower level of domestication. Conclusions: The integration of REML/BLUP analyses, stability parameters, and ideotype-based multi-trait selection provided a robust framework for identifying elite P. nicorae ecotypes. These findings reinforce the strategic importance of this species as a valuable genetic resource for the development of adapted and productive forage cultivars in subtropical environments. Full article

Paulownia trees are grown globally for their robust timber, agroforestry, and effective carbon dioxide drawdown. China possesses rich Paulownia germplasm resources, offering favorable material for the genetic improvement. Understanding the taxonomy and phylogenetic relationships of Paulownia species is essential for the advancement of germplasm innovation. In this study, we re-sequenced 67 typical accessions of 11 species within the Paulownia genus. A total of 16,163,790 high-quality single nucleotide polymorphisms (SNPs) were identified. Based on these markers, these accessions were classified into three groups: P. fortunei and P. lampropylla (Group I); P. tomentosa, P. fargesii, and P. kawakamii (Group II); and P. taiwaniana, P. jianshiensis, P. catalpifolia, P. elongata, P. ichangensis, and P. albiphloea (Group III). Using maximum likelihood estimation, population genetic structure analysis revealed that the 11 species originated from four different ancestral populations. The two predominant breeding species—P. fortunei and P. tomentosa—exhibit divergent origins: P. fortunei arose from hybridization between two ancestral species followed by complex admixture, whereas P. tomentosa retains a predominantly singular ancestral lineage, with traces of P. kawakamii. The genetic diversity (π) of P. tomentosa was 0.002588, which was considerably lower than that of P. fortunei (0.004181) suggesting that P. tomentosa is subjected to a stronger breeding selection during the evolution than P. fortunei. A total of 59 selected regions and 65 genes were identified by selective sweep analysis. These genes may be involved in biological processes such as morphological development and response to abiotic stress and hormonal activity regulation. These findings provide valuable references for further research on the genetic differentiation and adaptive evolutionary mechanisms of Paulownia species, laying a foundation for future germplasm innovation and variety improvement. Full article

Climate change poses serious challenges to Mediterranean crops such as the olive tree (Olea europaea L. subsp. europaea), underscoring the need for cultivars with improved drought tolerance and disease resistance. This study investigates variability in leaf and wood traits among Moroccan and introduced olive cultivars and their crossbreed genotypes grown under similar conditions. Specifically, we assessed (1) variation in key functional traits, (2) the effects of crossbreeding combinations, and (3) trait syndromes shaped by selection. Results showed substantial intraspecific variation in leaf traits, including specific leaf area (SLA), specific leaf water content (SLWC), stomatal size (SS), and density (SD), indicating diverse strategies for resource use and plasticity. Crossbreed genotypes generally displayed higher SLWC and lower SLA, reflecting adaptation to water stress. Wood traits, particularly vessel size (SVS) and number (NVS), also varied, revealing trade-offs between hydraulic efficiency and safety. Notably, an increase in vessel size and hydraulic conductivity was correlated with oil content (OC%), while OC% increased with higher vessel and stomatal densities. Larger stomata increased conductance and fruit growth, while lower SLA was linked to higher yield. Multivariate analysis distinguished two genotype groups, consistent with parental combinations. Overall, crossbreeding generated novel functional diversity that may enhance adaptive potential. These findings highlight the value of integrating functional and anatomical traits into olive breeding programs to improve resilience and productivity under climate change. Full article

Analysis of selection signatures in the genomes of farm animals enables the detection of genomic regions affected by selection and contributes to the identification of genes underlying adaptive and productive traits. This research aimed to identify loci under selection pressure and to detect candidate genes in Dzhalgin Merino sheep by performing a comparative genomic analysis with the related Australian Merino and Rambouillet breeds. A total of 293 animals were included in the analysis, comprising Dzhalgin Merino (n = 53), Australian Merino (n = 50), Australian Industry Merino (n = 88), and Rambouillet (n = 102). Whole-genome SNP genotyping data for Dzhalgin Merino were generated within this study, while data for Australian Merino, Australian Industry Merino, and Rambouillet were obtained from the SheepHapMap project. For the purposes of analysis, Australian Merino and Australian Industry Merino were combined into a single group (n = 138). To enhance the reliability of the results, three independent methods were employed to detect selection signatures: the fixation index (FST), analysis of linkage disequilibrium variation (varLD), and the cross-population number of segregating sites by length (xp-nSL). The study showed that Dzhalgin Merino have unique genetic signatures potentially associated with adaptation and productivity, which opens up new opportunities for their selection. The identified genes can become the basis for developing new breeding programs aimed at improving both the productive qualities and the adaptive abilities of the breed. Further research should be aimed at a detailed investigation of gene structure within loci under selection pressure and at clarifying the mechanisms by which these genes influence animal phenotypes. A total of 185 genes were identified within genomic regions exhibiting selection signatures. Among these, particular attention was given to EPHA6, MLLT3, ROBO1, KIAA0753, MED31, SLC13A5, and ELAVL4, which are involved in biological processes such as growth, development, and reproduction. The identified genes represent potential targets for breeding programs aimed at increasing productivity and adaptive capacity of the breed. Full article

Accurate prediction of cultivar performance across diverse environments is crucial for breeding and recommendation systems, helping to reduce the yield gap, the difference between potential and actual yields, which is often widened by poor cultivar selection. This study assessed the adaptability of winter wheat (Triticum aestivum L.) cultivars using a linear mixed-model framework combined with environmental mean regression. The model was trained on yield data from 19 locations over nine years (2015–2023) and validated independently using 2024 data. To ensure robustness, outliers were removed and cultivars with fewer than 30 observations excluded. The model accounted for genotype-by-environment (G×E) interactions and produced adjusted means for each location–year–management combination. These were used in cultivar-specific regressions to estimate yield response across environments. The approach showed strong predictive performance, with a Pearson correlation of 0.958 between predicted and observed yields in the validation year. Results highlight the model’s potential to inform cultivar recommendations, including for less-tested cultivars. This framework offers a practical tool for data-driven decision-making in plant breeding and agronomy, especially under variable growing conditions. Full article

The stable marine environment is conducive to the development of the aquaculture industry. However, with the change of seawater salinity in recent years, it has had a great impact on the survival and breeding of cephalopods such as Sepia esculenta. In this study, biochemical measurement and transcriptome sequencing were performed on the larvae of S. esculenta after different salinity stresses (salinity of 20 ppt and 40 ppt), and the reliability of transcriptome results was proved by physiological indexes. We performed Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis, and gene set enrichment analysis (GSEA) on all annotated genes, and gene sets were identified, including chemokine signaling pathways, MAPK signaling pathways, and cell cycle pathways. Finally, we constructed the protein-protein interaction networks (PPI) between the core genes in these gene sets and differentially expressed genes (DEGs) to identify key genes, including NFKBIA. Among them, the NFKBIA is not only a core gene in the chemokine signaling pathway gene set under four stresses but also has a high number of protein interactions. We speculate that this gene may have important immunomodulatory functions in the face of different time and salinity stresses. The results of our study explored the molecular mechanism of S. esculenta in the face of environmental stress, revealed the key molecular regulatory pathways for its survival and adaptation under complex environmental pressures, and may provide insights relevant to the development of S. esculenta pond culture. Full article