BMC Plant Biology最新文献

Background: The Three-Amino-Acid-Loop-Extension (TALE) transcription factors are key regulators of plant development and stress responses. However, a systematic study of the TALE gene family in Paulownia fortunei has not been reported to date.

Results: Here, we conducted the first genome-wide analysis and identified 38 PfTALE genes, which were phylogenetically classified into the KNOXI, KNOXII, and BELL subfamilies. These genes were unevenly distributed across 15 chromosomes. Promoter analysis revealed abundant cis-elements associated with light, hormones, and stress. Transcriptome profiling and qRT-PCR analyses showed that PfTALEs were differentially induced by drought, salt, and phytoplasma infection. Among them, PfTALE5, PfTALE12, PfTALE16, and PfTALE18 were significantly responsive to all three stresses, suggesting pivotal roles in stress adaptation. Notably, PfTALE5 exhibited consistent and strong upregulation under all stress conditions and was localized to both the nucleus and cytomembrane. Furthermore, yeast two-hybrid assays and molecular docking confirmed that PfTALE5 physically interacts with PfKNAT7 via hydrogen bonds, implying their cooperative function in stress response regulation.

Conclusions: Our study provides the first comprehensive genomic and functional insights into the TALE gene family in P. fortunei, highlighting PfTALE5 as a key regulator conferring multi-stress resilience. These findings offer valuable genetic targets and strategic guidance for breeding stress-resistant woody cultivars.

Background: The southeastern United States holds immense potential for producing cellulosic feedstocks to support the emerging biofuel industry. However, the development of a viable cellulosic biofuel sector depends on consistent, site-specific, and seasonally available biomass supply. Biomass sorghum has emerged as a promising annual feedstock, but understanding its growth dynamics and environmental sensitivities is essential for optimizing yield and supply logistics.

Methods: A four-year, multi-location study was conducted across six sites in the southeastern US to assess the influence of genotype, environment, and management on biomass sorghum growth and productivity. The objectives were to: (1) quantify the growth and biomass dynamics of biomass sorghum under different environments in the Southeast US and 2) estimate early harvest yield penalties based on its seasonal biomass growth patterns.

Results: Stalk density and plant height varied significantly across sites, years, and genotypes, reflecting strong genotype × environment interactions. Biomass accumulation followed a sigmoid growth pattern, with differences in heat unit requirements and the number of days to reach maximum biomass yield. Northern sites exhibited faster biomass accumulation but shorter growing seasons and higher early harvest penalties of up to 25%. End-of-season biomass ranged from 9.3 to 21.7 Mg ha⁻¹, with site accounting for the greatest source of variation, followed by site × year interaction.

Conclusions: This study reveals strong spatiotemporal variability in biomass sorghum growth and yield across environments. The results emphasize the need for site-specific genotype selection, management strategies, and harvest scheduling to minimize yield losses and enhance feedstock reliability. These insights contribute to optimizing biomass sorghum production and strengthening sustainable bioenergy systems in the southeastern US.

This research highlights the complex interplay between growth, flowering fruit yield, nutrient dynamics, physiological responses and overall tree health in determining the performance of different apple scion-rootstock combinations in high-density plating system. Among these, 'Gala Schniga Schnico' budded on EMLA 111 rootstock exhibited exhibited the most vigorous vegetative growth which recorded the highest values for plant height, shoot growth, tree girth, leaf area, trunk cross-sectional area (TCSA), canopy diameter and tree canopy volume (TCV). In contrast, Jeromine/EMLA 111 combination showed the earliest phenological development, including pink bud stage, first flower opening, and full bloom, suggesting its potential for early harvest. Gala Schniga Schnico/EMLA 111 also recorded the longest flowering duration, which may enhance fruit set through prolonged pollination opportunities. Highest spur density was observed in Schlect Spur/EMLA 111, whereas the highest fruit set was exhibited in Gala Schniga Schnico/EMLA 9. Furthermore, Gala Schniga Schnico on both EMLA 111 and EMLA 9 consistently produced the highest fruit yield followed by Jeromine and Red Velox cultivars. Total carbohydrate partitioning revealed that non-fruiting shoots contained higher total carbohydrate concentrations compared to fruiting shoots, reflecting the metabolic demands of reproductive growth. Notably, the cultivar King Roat accumulated the highest total carbohydrate content among the cultivars tested. Leaf nutrient analysis indicated Gala Schniga Schnico/EMLA 111 had superior nutrient status, suggesting more efficient nutrient uptake and utilization. Among the rootstocks, EMLA 111 consistently supported better vegetative growth, yield performance and physiological efficiency. Based on the evaluation of agro-morphometric traits, it can be concluded that the cultivars, 'Gala Schniga Schnico', 'Jeromine' and 'Red Velox' on EMLA 111 and EMLA 9 combinations offer promising alternatives for enhancing productivity, fruit quality and adaptability in high-altitude orchard high density systems in Himalayan ecosystem.

This study evaluated the phenotypic stability of five Egyptian soybean genotypes (Giza 111, Giza 22, and lines 105, 127, and 129) across six environments comprising three water regimes of irrigation levels of 100% (normal), 75% (moderate drought), and 50% (severe drought) of field capacity, evaluated over two growing seasons (2023 and 2024). Morpho-developmental traits (germination percentage, days to flowering and maturity, plant height, hair number, defoliation percentage), yield components (branch number, seed size, pod number, empty pod number, 100-seed weight, seed yield per plant and feddan), and seed biochemical composition (protein and oil contents) were assessed. Morphological characterization revealed that Giza 22 and Line 101 exhibited superior germination rates, while Line 129 demonstrated maximum plant height and number of hairs. Giza 22 showed the earliest maturity date. For yield component analysis, Lines 127 and 129 achieved the highest seed yield, while Giza 22 displayed superior seed size and 100-seed weight, whereas Line 105 exhibited the lowest number of empty pods. The seed biochemical analysis demonstrated that Line 129 achieved maximum protein levels, whereas Line 105 attained the highest oil content. Furthermore, multi-trait stability assessment identified Giza 111 and Line 129 as phenotypically stable across multiple parameters, with Line 129 exhibiting optimal performance-stability equilibrium. This was corroborated by the weighted average of absolute scores from BLUPs (WAASB), where Line 129 recorded the lowest WAASB value, indicating superior multi-trait stability. Collectively, these findings suggest that Line 129 is a stable, high-yielding soybean genotype suited to variable conditions, including drought, making it a valuable resource for improving yield and stability in water-limited environments in Egypt. Further research should investigate the molecular and physiological traits behind its performance and the potential of Giza 111 in breeding for drought tolerance.

Recombination is one of the forces that helps to shape the genetic diversity of populations by facilitating crossover events, in which homologous chromosomal sequences are exchanged. This process generates novel allelic combinations, enabling populations to adapt to selection pressures. Understanding the factors influencing crossover placement is vital for breeders, as it allows for the targeted transfer of specific traits or genes to offspring. In this study, we explore three different types of genome features, such as k-mers, expression elements and repetitive elements, and their relationships with recombination in ten intraspecific populations of Brassica oleracea, and one interspecific cross between two tomato species; Solanum lycopersicum and Solanum pimpinellifolium. Our results reveal that specific AT-rich k-mers, expression elements from gene annotation, and certain repetitive elements are positively associated with meiotic recombination. In contrast, CG-rich k-mers and other repetitive elements, such as some LTR retrotransposon families, show negative associations. These features were subsequently used to train regression-based machine learning models capable of predicting recombination patterns along chromosomes. Our findings suggest that plant genomes contain sufficient information to infer recombination landscapes along chromosomes.

Rapeseed (Brassica napus L.) is a valuable oilseed crop due to its high nutritional value and rich oil content, making it a major source of edible oil. However, frequent drought events, aggravated by climate change, pose challenges to its productivity. Whereas a set of genotypes was previously investigated for their response to early drought during germination and seedling stages, the present study aimed to identify those genotypes exhibiting their tolerance to late-stage drought (occurring at flowering and maturity), and to elucidate their adaptive mechanisms, via an integrative multi-trait approach. A pot experiment was conducted under controlled greenhouse conditions, using a completely randomized design with three replications. The genotypes were evaluated for agromorphological, physiological, and biochemical parameters under two irrigation regimes (100% and 50% field capacity). Drought stress significantly reduced growth, yield components, and chlorophyll content. In contrast, water deficit induced accumulation of H₂O₂, MDA, relative electrical conductivity (EL), proline, and soluble sugars by about 40% and increased superoxide dismutase (SOD) and catalase activities by more than 42%. Nevertheless, the genotypes reacted differently to stress. Compared to the other genotypes, the varieties 'Nap9', 'Marina', 'Moufida', 'Baraka', and 'Redana' exhibited higher SPAD and Fv/Fm levels, along with lower concentrations of H₂O₂, MDA, and EL, indicating better drought tolerance. This tolerance was associated with increased enzyme activity and greater osmolyte accumulation. Drought reduced seed yield by 40% and increased H₂O₂ and MDA concentrations by 71% on average, whereas 'Nap9', 'Marina', and 'Redana' limited the increase in EL to only 20% while maintaining 12-14 g plant⁻¹ seed yield under stress. In particular, 'Nap9', 'Marina', and 'Redana' maintained better growth and higher productivity under drought, indicating their higher resilience. These genotypes could be a valuable germplasm for developing drought-tolerant rapeseed cultivars.

Background: Root exudation is an important trait that enables plants to shape their interactions with soil-borne organisms. Amino acids present in root exudates play important roles in bacterial chemotaxis, bacterial metabolism, and root colonization, contributing to plant nutrition and health. Notwithstanding the importance of amino acids in shaping the rhizosphere microbiome, the identities of the plant amino acid transporters that mediate their root exudation have remained elusive.

Results: Here, we report that the Arabidopsis UMAMIT30 transporter, robustly expressed in root and shoot tissues, significantly contributes to amino acid root exudation. umamit30 loss-of-function mutants were compromised for amino acid root exudation as shown by the low concentration of amino acids, particularly glutamine, recovered from root exudates compared to wild-type plants. Amino acid quantification, as well as uptake and secretion assessments using radiolabelled glutamine, revealed that the shoots of umamit30 accumulate amino acids and have a reduced capacity to secrete glutamine, impacting root exudation.

Conclusions: Our results identify UMAMIT30 as a broadly specific amino acid exporter strongly expressed in Arabidopsis vasculature. Loss-of-function mutants displayed reduced amino acid levels in root exudates, with significant drops in glutamine and asparagine among others, yet exhibited no detectable growth defects under our growth conditions. UMAMIT30 disruption led to elevated shoot amino acid content and reduced glutamine efflux from shoots, suggesting a role in phloem uploading as an upstream step necessary for root exudation. Despite decreased levels of root-exuded amino acids, the plant growth-promotion conferred by the soil-borne beneficial bacterium Pseudomonas simiae WCS417r remained unmodified in umamit30 mutants.