Search Results (429)

Cannabis sativa L. (2n = 2x = 20) is a widely recognized species within the Cannabaceae family. Despite its utilization for medicinal, recreational, and industrial purposes, alongside its extensive historical background, the number of genetic and biotechnological studies of this plant species has decreased due to legal ramifications and prohibition campaigns associated with its use and cultivation. For many years, the development of novel varieties has been pursued solely by cultivators, as domestic growers have transitioned their work from cultivation to breeding Cannabis lineages. Recently, the application of genomics has facilitated a surge in methodologies aimed at marker-assisted selection, germplasm management, genetic differentiation, authentication of cultivated varieties or cultivars, and forensic applications such as safeguarding intellectual property rights. Nevertheless, the utilization of molecular markers for the advancement of commercial varieties through marker-assisted breeding (MAB) frameworks remains rare. This investigation was designed to evaluate a previously established informative microsatellite (SSR) array for the genotyping of drug-type Cannabis sativa cultivars derived from seeds of European origin. A total of 171 samples from 20 varieties were collected from European distributors and analyzed for genetic uniformity and population structure. The results were then compared with previously analyzed hemp samples and drug-type samples of Canadian origin, revealing the identification capabilities of our SSR genotyping method. Full article

This study aims to elucidate the molecular mechanisms underlying cyanogenic glycoside accumulation in flax. As an important oil and fiber crop, the nutritional value of flax is compromised by the toxicity of cyanogenic glycoside. To clarify the key genetic regulators and temporal patterns of cyanogenic glycoside biosynthesis, transcriptomic sequencing was performed on seeds from high- and low-cyanogenic glycoside flax varieties (‘MONTANA16’ and ‘Xilibai’) at three developmental stages: bud stage, full flowering stage, and capsule-setting stage. A total of 127.25 Gb of high-quality data was obtained, with an alignment rate exceeding 87.80%. We identified 31,623 differentially expressed genes (DEGs), which exhibited distinct variety- and stage-specific expression patterns. Principal component analysis (PCA) and hierarchical clustering demonstrated strong reproducibility among biological replicates and revealed the seed pod formation stage as the period with the most significant varietal differences, suggesting it may represent a critical regulatory window for cyanogenic glycoside synthesis. GO and KEGG enrichment analyses indicated that DEGs were primarily involved in metabolic processes (including secondary metabolism and carbohydrate metabolism), oxidoreductase activity, and transmembrane transport functions. Of these, the cytochrome P450 pathway was most significantly enriched at the full bloom stage (H2 vs. L2). A total of 15 LuCYP450 and 13 LuUGT85 family genes were identified, and their expression patterns were closely associated with cyanogenic glycoside accumulation: In high-cyanogenic varieties, LuCYP450-8 was continuously upregulated, and LuUGT85-12 was significantly activated during later stages. Conversely, in low-cyanogenic varieties, high expression of LuCYP450-2/14 may inhibit synthesis. These findings systematically reveal the genetic basis and temporal dynamics of cyanogenic glycoside biosynthesis in flax and highlight the seed pod formation stage as a decisive regulatory window for cyanogenic glycoside synthesis. This study provides new insights into the coordinated regulation of cyanogenic pathways and establishes a molecular foundation for breeding flax varieties with low CNG content without compromising agronomic traits. Full article

Submergence during germination is a major barrier to the adoption of direct-seeded rice (DSR). Despite its importance in overcoming this barrier, the genetic architecture underlying the rapid coleoptile elongation under submergence remains largely elusive. Through screening among 20 different rice cultivars, a submergence-tolerant cultivar Xian133 and a sensitive cultivar Chang15 were obtained. Comparative transcriptomics and whole-genome resequencing were conducted between these two cultivars. The results show that rapid germination under flooding is driven primarily by transcriptional reprogramming rather than by antagonistic gene regulation. Transcriptome-wide analyses revealed a significant enrichment of the amino sugar and nucleotide sugar metabolism pathway in tolerant cultivar. This was further supported by the fact that promoter variants at the key loci OscPGM and OsAGPL1 modulate the expression of these genes and emerge as principal determinants of coleoptile elongation capacity under hypoxia. The identified single-nucleotide polymorphisms (SNPs) within these regulatory regions provide promising molecular targets for marker-assisted breeding of DSR cultivars. Full article

β-D-xylosidases (BXLs) are pivotal enzymes in xylan degradation, playing essential roles in plant development and stress responses. In this study, we identified 29 GmBXL genes in soybean through homolog alignment. Phylogenetic analysis classified these genes into three groups, with Group III being legume-specific. The GmBXLs are unevenly distributed across 15 chromosomes, with their expansion driven by both tandem and segmental duplications. Conserved motif and domain analyses revealed functional conservation, particularly in family 3 of glycoside hydrolase domains. Promoter regions of GmBXLs are enriched with hormone-responsive and stress-related cis-elements, indicating their involvement in diverse biological processes. Tissue-specific expression analysis revealed differential GmBXLs expression across leaves, roots, flowers, and seeds, with GmBXL13 and GmBXL26 exhibiting notably high transcript levels in pods and seeds. Under salt stress, 26 GmBXLs exhibited significant expression changes, with 20 genes up-regulated in both leaves and roots, highlighting their roles in salt tolerance. These findings enhance our understanding of the evolutionary and functional characteristics of GmBXLs, providing valuable insights for molecular breeding of salt-tolerant soybean varieties. Full article

Understanding the genetic architecture of complex traits is crucial for crop improvement and molecular breeding. We developed a mutagenized soybean population using carbon ion beam irradiation and conducted genome-wide association studies (GWAS) to identify variants controlling key agronomic traits. Whole-genome resequencing of 199 M4 lines revealed 1.48 million SNPs, predominantly C→T transitions, with population structure analysis identifying three distinct genetic groups. GWAS across five traits revealed striking differences in genetic architecture: the podding habit showed extreme polygenic control with 87,029 significant associations of small effect, while pubescence color exhibited oligogenic inheritance with only 122 variants. Hundred-seed weight displayed moderate complexity (4637 associations) with the largest effect sizes (−3.74 to 5.03) and major QTLs on chromosomes 4, 7, and 15–20. Growth habit involved 12,136 SNPs, including a strong chromosome 3 association (−log₁₀(p-value) > 50). Flower color showed 2662 associations clustered on chromosome 15. Functional analysis of 18,542 candidate genes revealed trait-specific pathway enrichments: flavonoid biosynthesis for flower color, phloem transport for seed weight, auxin signaling for growth habit, and amino acid transport for podding habit. This study demonstrates how mutagenesis-induced variation, combined with association mapping, reveals evolutionary constraints that shape genetic architectures, providing insights for genetics-assisted breeding strategies. Full article

Chickpea (Cicer arietinum L.) is a key legume crop of global economic and nutritional importance, yet its cultivation in Kazakhstan is constrained by a narrow genetic base and exposure to stress-prone environments. To characterize the diversity available for breeding and conservation, 27 accessions (22 kabuli and 5 desi) were evaluated for phenotypic and molecular diversity to assess its potential for use in breeding programs. Seven agronomic traits were assessed, including plant height, the first pod’s height, the number of main stems per plant, and seed yield components. The collection showed considerable variability across traits, with the plant height ranging from 37 to 75 cm and hundred-seed weight ranging from 21 to 42 g. Strong positive correlations between the number of fertile nodes, number of seeds per plant, and yield per plant (r > 0.83) highlighted their utility as indirect selection criteria. Genotyping with 28 SSR markers revealed 110 alleles (mean 3.9 ± 0.4 per locus) with moderate polymorphism (PIC = 0.493 ± 0.089). Loci CaM00495 and TAI71 were highly informative (PIC > 0.804), while two accessions showed low polymorphism, indicating genetic uniformity. Population structure analysis grouped accessions into four highly admixed clusters. Overall, Kazakh chickpea germplasm exhibits substantial phenotypic and genetic diversity under optimal conditions, providing valuable preliminary data for selecting parental lines for future breeding programs, which should include targeted stress screening to evaluate resilience. Full article

Phosphoethanolamine N-methyltransferase (PEAMT) is a key enzyme that catalyzes three successive methylation steps of phosphoethanolamine (P-EA) to phosphocholine (P-Cho). Meanwhile, P-Cho is a major precursor of phosphatidylcholine (PC) and glycine betaine (GB), which are involved in cell signal transduction, stress response, etc. Therefore, the PEAMT gene plays an essential role in plant growth and development as well as stress resistance. There are two homologous PEAMT genes in rice (Oryza sativa L. ssp. japonica), namely, OsPEAMT1 and OsPEAMT2. However, there has not been any comprehensive functional analysis of these two genes. Here, we employed bioinformatics methods to analyze the amino acid sequences and promoters of OsPEAMT1 and OsPEAMT2, and found that both proteins contain two methyltransferase domains. OsPEAMT1 is highly similar with ZmPEAMT, and OsPEAMT2 is closely related to LmPEAMT and TaPEAMT. There are abundant plant hormone response elements, stress response elements and low-temperature response elements in the promoters of OsPEAMT1 and OsPEAMT2. The in vitro enzymatic activity assays of recombinant proteins of OsPEAMT1 and OsPEAMT2 indicated that they can catalyze the production of P-Cho from P-EA, respectively. Meanwhile, the endogenous P-Cho content increased significantly (p < 0.05) when exogenous P-EA was added to rice. These indicate that OsPEAMT1 and OsPEAMT2 proteins have catalytic functions in vivo and in vitro. The expression patterns of both genes are different in different tissues, flowers and seeds at various developmental stages. Additionally, both genes have different responses to salt and low-temperature stress. This study supplies valuable insights into the function of OsPEAMT1 and OsPEAMT2, and it will provide key targets for rice molecular breeding, offering important insights for the development of rice with stress resistance and high yield. Full article

The document is an updated review, starting from the Special Issue “Molecular Breeding for Abiotic Stress Tolerance in Crops” published in the Int. J. Mol. Sci. It reviews molecular breeding strategies to enhance abiotic stress tolerance in crops, addressing challenges like drought, salinity, temperature extremes, and waterlogging, which threaten global food security. Climate change intensifies these stresses, making it critical to develop resilient crop varieties. Plants adapt to stress through mechanisms such as hormonal regulation (e.g., ABA, ethylene), antioxidant defense (e.g., SOD, CAT), osmotic adjustment (e.g., proline accumulation), and gene expression regulation via transcription factors like MYB and WRKY. Advanced tools, such as CRISPR/Cas9 genome editing, enable precise modifications of stress-related genes, improving tolerance without compromising yield. Examples include rice (OsRR22, OsDST) and wheat (TaERF3, TaHKT1;5). Epigenetic regulation, including DNA methylation and histone modifications, also plays a role in stress adaptation. Specific studies focused on polyamine seed priming for improved germination and stress resistance, cadmium detoxification mechanisms, and genome-wide association studies (GWAS) to identify genetic markers for salt tolerance and yield. Research on salinity tolerance in wheat emphasizes sodium exclusion and tissue tolerance mechanisms. Future perspectives focus on genetic engineering, molecular markers, epigenetic studies, and functional validation to address environmental stress challenges, including the use of AI and machine learning to manage the large amount of data. The review underscores the importance of translating molecular findings into practical applications to ensure sustainable crop production under changing climates. Full article

Grain shape is a critical determinant of rice yield, quality, and market value. Recent advances in molecular biology, genomics, and systems biology have revealed a complex regulatory network governing grain development, integrating genetic loci, plant hormone signaling, transcriptional regulation, protein ubiquitination, epigenetic modifications, and environmental cues. This review summarizes key genetic components such as QTLs, transcription factors, and hormone pathways—including auxin, cytokinin, gibberellin, brassinosteroids, and abscisic acid—that influence seed size through regulation of cell division, expansion, and nutrient allocation. The roles of the ubiquitin–proteasome system, miRNAs, lncRNAs, and chromatin remodeling are also discussed, highlighting their importance in fine-tuning grain development. Furthermore, we examine environmental factors that impact grain filling and size, including temperature, light, and nutrient availability. We also explore cutting-edge breeding strategies such as gene editing, functional marker development, and wild germplasm utilization, along with the integration of multi-omics platforms like RiceAtlas to enable intelligent and ecological zone-specific precision breeding. Finally, challenges such as pleiotropy and non-additive gene interactions are discussed, and future directions are proposed to enhance grain shape improvement for yield stability and food security. Full article

The increasing demand for novel cut chrysanthemum cultivars has underscored the significance of precision breeding techniques, with particular emphasis on hybridization and molecular tools. This study aimed to assess the cross-compatibility of selected chrysanthemum cultivars and to evaluate the genetic, quantitative, and qualitative diversity among the resulting F₁ progenies. A total of six hybrid combinations were generated using five commercial parental cultivars. Ploidy levels were determined via flow cytometry and chromosome counting, confirming that all parents were allohexaploid (2n = 6x = 54). Pollen viability and germination rates varied significantly among male parents, influencing hybridization success. A total of 30,391 seeds were obtained, with germination rates ranging from 2.69% to 10.73%, depending on the cross combination. F₁ progenies showed considerable phenotypic variability in flowering time, flower stalk length, flower diameter, and branch weight. Molecular characterization using eight iPBS primers revealed a high polymorphism rate (93%) with a mean Polymorphism Information Content (PIC) value of 0.614, confirming substantial genetic diversity among genotypes. Cluster and principal coordinate analyses demonstrated that most F₁ genotypes grouped closely with their maternal parents, although unique genomic variations were also detected. The integration of morphological and molecular data provides valuable insights for selecting superior genotypes and optimizing breeding strategies. This study highlights the importance of evaluating hybridization potential and genetic diversity in the development of commercially viable cut chrysanthemum cultivars. Full article

Background: Adverse environmental conditions and an ever-increasing world population require devising and designing a roadmap for the next generation of wheat crops for high productivity and resilience to climate change. As such, a fundamental understanding of wheat metabolism and molecular descriptors of wheat seed potentials and quality is a sine qua non step. Objectives: In this study we investigated the seed metabolomes of five wheat cultivars to identify differential metabolic profiles and cultivar-related metabolic markers. Methods: Liquid chromatography-mass spectrometry (LC-MS) combined with computational strategies and functional analyses was applied. Metabolites were extracted using methanol, and samples were analysed on an LC-MS/MS system. Results: The results revealed that the extracted wheat cultivar seed metabolomes spanned a broad range of metabolite classes, including alkaloids, sugars, phenolics, amino acids, hormones, TCA compounds and lipids. Furthermore, the results also revealed key metabolic markers differentiating the wheat cultivars from one another, such as lipids (i.e., MGMG and 13-HODE) and flavonoids (i.e., rutin, tricin and vitexin), amongst many others. Conclusions: Such insights are important in assessing seed quality as well as in the selection of markers for seed nutrient and quality trait improvement in wheat breeding programmes. As such, this work generates novel actionable knowledge, a comprehensive metabolomic landscape of wheat seeds and potential markers for cultivar differentiation and quality assessment, which is essential for sustainable and improved wheat production. Thus, the study contributes towards the realisation of sustainable food security, an urgent call for action in a global partnership, as articulated in the United Nations Sustainable Development Goals, particularly zero hunger. Full article

Tree peony (Paeonia ostii) is widely cultivated in China as a traditional medicine and a new high-quality woody oil crop. Enhancing seed yield has become a primary breeding objective in the industrial development of oil tree peonies. Pollination and successful fertilization are essential for optimal seed yield. However, the molecular mechanisms underlying pollination and fertilization in P. ostii remain unclear. In this study, comparative transcriptomic and genetic analyses were conducted to investigate the pistils under different pollination periods of P. ostii ‘Fengdanbai’. Compared with pre-pollination, differentially expressed genes (DEGs) were screened from pistils 48 h after pollination, when most of the pollen tubes had reached the bottom of the style. Functional annotation indicated that these DEGs were involved in hormone signaling and carbohydrate metabolism pathways. Transcription factors and receptor-like kinases play a key role in pollen development, pollen tube growth, and carpel development. Key DEGs (PoUNE10 and PoLIM1) influenced pollination and fertilization and were characterized. Phylogenetic, promoter, and co-expression analyses suggest that they may affect plant pollination, fertilization, and seed yield through pathways such as hormone signaling and photosynthesis in P. ostii ‘Fengdanbai’. Our findings illustrate the molecular changes after pollination and fertilization in P. ostii ‘Fengdanbai’ and provide the molecular characterization of two key genes. These results provide insights into the molecular mechanisms underlying pollination and fertilization in tree peony and suggest potential candidate genes for molecular breeding aimed at improving seed yield in the species. Full article

As a globally significant fruit crop, litchi (Litchi chinensis Sonn.) exhibits substantial variation in seed size, which is a key determinant of fruit quality. However, the lack of molecular markers closely associated with seed-related traits has hindered targeted breeding efforts. In this study, we systematically evaluated six critical traits—single fruit weight, seed weight, seed length, seed width, edible rate, and seed-to-fruit weight ratio—across 131 early-maturing litchi accessions. Hierarchical clustering analysis (HCA) and principal component analysis (PCA) revealed a clear bifurcation of these accessions into two distinct groups based on seed size-related traits. Using bulked segregant analysis sequencing (BSA-seq), we identified a candidate genomic region (24.93–25.69 Mb) on chromosome 5, potentially regulating litchi seed size. Within this region, 1600 single-nucleotide polymorphisms (SNPs) and 314 insertion/deletion mutations (InDels) exhibited significant divergences between the extreme pools. To validate these findings, we performed PCR-based screening on 87 litchi accessions. Two InDel markers demonstrated strong phenotypic associations: Chr5_25610680_InDel showed highly significant correlations with seed weight, edible rate, seed length, seed width, and seed-to-fruit weight ratio, explaining 22.60–35.54% of phenotypic variation. Meanwhile, Chr5_25585686_InDel was significantly associated with seed weight and edible rate, accounting for 18.66% and 18.94% of the phenotypic variation, respectively. These findings provide valuable molecular markers for marker-assisted breeding of litchi seed size, offering a promising avenue to advance precision breeding in this economically important crop. Full article

Camelina sativa is an oilseed crop that has shown strong promise as a biofuel feedstock. The profile of fatty acids greatly influences the oil quality; however, genetic mechanisms that determine the natural variation of fatty acid composition in camelina are not fully understood. A genome wide association study (GWAS) was performed to uncover genetic loci that may contribute to the contents of major fatty acids such as oleic and linolenic acids in camelina seed. Two approaches were taken to improve the GWAS efficiency. First, growing a diversity panel of 212 accessions in four locations and two nitrogen fertilization conditions revealed great variation in fatty acid contents in seeds. Second, using an improved reference genome, abundant markers, including 203,320 single nucleotide polymorphisms (SNPs) and 99,067 insertions/deletions (indels), were developed, which refined the population structure of the diversity panel. GWAS resulted in 118 genetic markers across 31 trait/treatment conditions. Closely linked markers were determined based on linkage decay and by comparing secondarily associated markers when highly associated ones were removed. Candidate genes were examined by comparing the pangenomes of 12 high-quality reference genomes. This study provides new resources to understand seed lipid metabolism and improve camelina oils through molecular breeding. Full article

Common vetch (Vicia sativa L.) is a globally green manure and forage crop, cultivated extensively worldwide. Its seeds serve as an important concentrated feed. Due to the late release of the reference genome, few studies were conducted to analyze the genetic mechanisms of grain yield, which hindered the progress of common vetch breeding. Marker-assisted selection (MAS) is the best and most effective way to accelerate the genetic improvement of grain yield-related traits in common vetch. In this study, we performed a genome-wide association study (GWAS) using the high-density single nucleotide polymorphism (SNP) data obtained through re-sequencing to better understand the genetic basis of grain yield-related traits. In total, six grain yield-related traits were evaluated in 172 accessions mainly sourced from China and Russia, across four environments, including branches per plant (NB), pod length (PL), number of pods per plant (NP), number of grains per pod (NG), hundred-grain weight (HGW), and grain yield (GY). Population structure analysis of the 172 accessions revealed four distinct subpopulations, exhibiting strong geographical correlation. In total, 38 loci have been identified as significantly associated with six grain yield-related traits, accounting for 13.3–31.7% of the phenotypic variances. Among them, qGY1.1 and qNG1.1, qNG2.2 and qPL2.1, qNG3.2 and qGY3.2, qNG4.1 and qPL4.1, qGY4.1 and qHGW4.1, qNG6.1 and qPL6.1, and qNB6.2 and qGY6.2 exhibit overlapping regions, suggesting that these regions are pleiotropic and should be prioritized for further research and breeding. In total, 12 candidate genes encoding auxin response factor, F-box repeat protein, gibberellin receptor, serine/threonine-protein kinase-like protein, and cellulose synthase-like protein were identified. Furthermore, we successfully developed and verified a kompetitive allele-specific PCR (KASP) marker (Kasp-NB6.2) for the number of branches. These findings provide molecular insights into grain yield-related traits in common vetch and offer valuable loci and molecular tools for MAS breeding. Full article