Search Results (7,405)

Dehydration response element binding proteins (DREBs) have been identified as major regulators of cold acclimatization in many angiosperms. Cold stress is one of the primary abiotic stresses affecting kiwifruit growth and development. However, kiwifruit is currently one of the most widely consumed fruits worldwide because of its high nutritional value. 5-Aminolevulinic acid (5-ALA) is a nonprotein amino acid known for its distinct promotional effects on plant resistance, growth, and development. However, studies on the function of the kiwifruit DREB gene in alleviating low-temperature stress in its seedlings via exogenous 5-ALA have not been reported. Therefore, in this study, we performed a genome-wide identification of DREB gene family members in kiwifruit and analyzed the regulatory effects of exogenous 5-ALA on kiwifruit DREB genes under low-temperature stress. A total of 193 DREB genes were identified on 29 chromosomes. Phylogenetic analysis classified these genes into six subfamilies. Although there were some differences in cis-elements among subfamilies, all of them contained more biotic or abiotic stresses and hormone-related cis-acting elements. GO and KEGG enrichment analyses revealed that AcDREB plays an essential role in hormone signaling, metabolic processes, and the response to adverse stress. Under low-temperature stress, the application of exogenous 5-ALA inhibited the accumulation of APX and DHAR, promoted an increase in chlorophyll, and increased the accumulation of enzymes and substances such as 5-ALA, MDHAR, GR, ASA, GAH, and GSSH, thereby accelerating ROS scavenging and increasing the cold hardiness of kiwifruits. Functional analysis revealed that 46 differentially expressed DREB genes, especially those encoding AcDREB69, AcDREB92, and AcDREB148, which are involved in ethylene signaling and defense signaling, and, after the transcription of downstream target genes is activated, are involved in the regulation of low-temperature-stressed kiwifruits by exogenous 5-ALA, thus improving the cold tolerance of kiwifruits. Notably, AcDREB69, AcDREB92, and AcDREB148 could serve as key genes for cold tolerance. This study is the first to investigate the function of AcDREB genes involved in the role of exogenous 5-ALA in regulating low-temperature stress, revealing the regulatory mechanism by which DREB is involved in the ability of exogenous 5-ALA to alleviate low-temperature stress. Full article

Domestication has been proven to significantly impact the biosynthesis of plant secondary metabolites. Cultivated green jujube (Ziziphus mauritiana Lam.), as an important autotetraploid fruit crop widely planted in tropical regions, exhibits differential physicochemical traits compared with its wild progenitor. To assess the traits lost in cultivated green jujube during domestication, the study performed comprehensive genomic, transcriptomic and metabolomic investigations of flavonoid pathways in wild and cultivated green jujube. Based on the four haplotype genomes of wild and cultivated green jujube, for the first time, the study bulk-identified 16 key gene families associated with flavonoid biosynthesis. Collinearity analysis revealed that tandem duplication was the predominant event in flavonoid-related genes rather than WGD. Through the expression profiles in different tissues, the distinct member of these gene families was classified as “redundant” or “functional”. Transcriptomic analyses illustrated the significant differential expressions (p < 0.05) of 13 flavonoid-related gene families in fruits of six cultivated and three wild green jujube accessions, except for FLS, LAR and PPO. The wild green jujube fruits accumulated more abundance of flavonoid metabolites than in cultivated fruits (p < 0.0001), as evidenced by upregulated chalcones, dihydroflavonol, isoflavones and flavonoid carbonoside. Gene–metabolite co-expression modules further validated the potential transcription regulators, such as BBX21, WRI1 and bZIP44. Together, the study suggested a genomic, transcriptomic and metabolic perspective for domestication regarding fruit flavonoid pathways in green jujube, which provides a valuable genetic resource for fruit quality improvement in cultivated green jujube. Full article

Soil salinity stress, intensified by extreme weather patterns, significantly threatens global watermelon [Citrullus lanatus (Thunb.) Matsum & Nakai] production. Watermelon, a moderately salt-sensitive crop, exhibits reduced germination, stunted growth, and impaired fruit yield and quality under saline conditions. As freshwater resources decline and agriculture’s dependency on irrigation leads to soil salinization, we need sustainable mitigation strategies for food security. Recent advances highlight the potential of using salt-tolerant rootstocks and breeding salt-resistant watermelon varieties as long-term genetic solutions for salinity. Conversely, agronomic interventions such as drip irrigation and soil amendments provide practical, short-term strategies to mitigate the impact of salt stress. Biostimulants represent another tool that imparts salinity tolerance in watermelon. Plant growth-promoting microbes (PGPMs) have emerged as promising biological tools to enhance watermelon tolerance to salt stress. PGPMs are an emerging tool for mitigating salinity stress; however, their potential in watermelon has not been fully explored. Nanobiochar and nanoparticles are another unexplored tool for addressing salinity stress. This review highlights the intricate relationship between soil salinity and watermelon production in a unique manner. It explores the various mitigation strategies, emphasizing the potential of PGPM as eco-friendly bio-inoculants for sustainable watermelon management in salt-affected soils. Full article

Colored shade nets have gained attention due to their ability to reduce light intensity and alter the light spectrum, thereby influencing vegetable crop quality and yield. However, limited research has examined their effects on jalapeño pepper (Capsicum annuum L.) growth and yield. This study evaluated the impact of four nets—black, red, silver, and white (40% shade factor)—compared to an unshaded control. The red net altered light quality by increasing the proportion of red and far-red wavelengths, while the other nets reduced light intensity without spectral modification. Although differences in mean air temperature were minimal between shaded and unshaded conditions, root zone temperatures were consistently lower under shade nets. Shade treatments significantly increased plant height, stem diameter, and leaf chlorophyll content relative to the unshaded control. The highest rates of leaf transpiration and stomatal conductance were recorded under unshaded and white net conditions. Net photosynthesis, electron transport rate, intercellular CO₂ concentration, or photosynthetic water use efficiency were similar among net treatments. Marketable and total yields did not differ significantly among net treatments in either year; however, in 2021, they were positively associated with light intensity. In conclusion, while colored shade nets promoted vegetative growth, they did not enhance fruit yield relative to unshaded conditions in jalapeño pepper. Full article

Thesium chinense Turcz. (T. chinense), a perennial herb in the Santalaceae family, exhibits potent antibacterial and anti-inflammatory properties. Transcriptome sequencing was performed on one- and two-year-old T. chinense plants across seedling, flowering, and fruiting stages (all sampled from the same location) using the illumina NovaSeq 6000 platform. A total of 58,706 unigenes were identified, including 1656 transcription factors (TFs). Further analysis classified these TFs into seven functional categories, enabling the reconstruction of a representative TF regulatory network. Differential expression analysis revealed that the number of differentially expressed genes (DEGs) ranged from 2000 to 5000 during different developmental stages in first-year plants, while varying between 1000 and 2000 in second-year plants. Comparative analysis of DEGs between one- and two-year-old plants showed that they were primarily associated with sesquiterpene, triterpene, and terpene skeleton biosynthesis, as well as other metabolic pathways. Additionally, analysis of key genes involved in flavonoid biosynthesis—the major bioactive compounds in T. chinense—revealed their predominant accumulation during the first year of growth. This study provides valuable insights into the developmental biology of T. chinense and establishes a foundation for future research on flavonoid biosynthesis pathway genes and their therapeutic applications. Full article

The plant microbiome plays a role in pathogen defense, but its role in different resistant varieties and ecological niches remains unclear. This study used 16S rRNA and ITS sequencing to investigate microbial communities and interactions in disease-resistant (PT) and susceptible (Bourbon) coffee varieties of five ecological niches: leaves, fruits, roots, rhizosphere soil, and non-rhizosphere soil. We found that the microbial communities differed significantly between the two varieties. The resistant variety was enriched in beneficial bacteria from the Actinobacteriota phylum and a stable, modular microbial network dominated by saprotrophic fungi. In contrast, the susceptible variety had a higher abundance of opportunistic pathogens and stress-indicator fungi, including Neurospora spp., which were more prominent in the rhizosphere and non-rhizosphere soils. These networks were fragile and dominated by pathotrophic fungi, reflecting ecological imbalance. Our findings show that plant disease resistance is influenced not only by host genetics but also by co-evolutionary interactions with the microbiome. These insights provide a foundation for developing targeted biocontrol strategies to manage plant-associated microbial communities. Full article

Phytophagous mites are considered pests in fruit crops, such as blackberries (Rubus spp. L.). These pests affect fruit quality and commercial value. This study aimed to evaluate the fluctuation of phytophagous mite populations and their impact on the quality of cultivated and wild blackberries in Jalisco, Mexico. Monthly sampling was carried out from November 2023 to May 2024. Mite families such as Diptilomiopidae, Eriophyidae, Tydeidae, Tarsonemidae, Tenuipalpidae, and Tetranychidae were identified, with a total of 6438 mites in the samples. An increase in mite populations was observed in March on cultivated blackberries and in April on wild ones, coinciding with the onset of plant development. The Eriophyidae family showed the highest relative abundance, with 34.2% in cultivated blackberries and 31.7% in wild ones in 2024. Quality parameters were evaluated in healthy and damaged blackberries. Damaged cultivated fruits showed lower weight (4.49 ± 1.44 g), smaller diameter (18.11 ± 2.00 mm), lower vitamin C content (4.76 ± 1.53 mg/100 g), and higher acidity (80.07 ± 19.10%). This study enabled the identification and monitoring of different mite families in blackberries, as well as an understanding of their population dynamics and impact on fruit quality. Full article

Agro-photovoltaics (APV) or agrivoltaic systems integrate crop cultivation with solar energy production, offering a promising solution through the dual-use of land. This two-year study (2023 and 2024) examined the effects of an APV system on rice production. The results indicated that APV arrays created spatially variable light environments, with shadow lengths following predictable solar azimuth patterns and cloudy conditions mitigating shading effects through enhanced diffuse light. Compared with CK (non-shadow area), inter-panel plots (BP) maintained 77% photosynthetic efficiency and 85.4% plant height, whereas the areas beneath the panel showed a significant decrease in the relative chlorophyll content (SPAD values), photosynthesis rates, and yield. BP plots preserved a 78% fruiting rate through adaptive stomatal regulation, whereas LP zones (directly under the low eave) exhibited 35% higher intercellular CO₂ because of the limited assimilation in shading. Rice yield losses were correlated with shading intensity, driven by reduced panicles and grain filling. Moreover, the APV system achieved a high land equivalent ratio of 148–149% by combining 65–66% rice yield with 82.5% photovoltaics output. Based on the microenvironment created by the APV system, optimal crop types and fertilisation are essential for enhancing agricultural yields and improving land use efficiency. Full article

Enhancing crop productivity through biological strategies is critical for agriculture, particularly under conventional farming systems heavily reliant on chemical inputs. Plant probiotic bacteria offer promising alternatives by promoting plant growth and yield. This is the first field study to assess the effects of biofertilization with native rhizobial strains Rhizobium sp. ACO-34A, Sinorhizobium mexicanum ITTG-R7^T, and S. chiapasense ITTG-S70^T on Solanum lycopersicum (tomato) cultivated under conventional farming conditions. Key parameters assessed include plant performance (plant height, plant stem width, plant dry weight, and chlorophyll content), fruit yield (fruits per plant, fruit height, fruit width, fruit weight, and estimated fruit volume), and macronutrient and micronutrient contents in plant tissue. Additionally, rhizospere bacterial communities were characterized through 16S rRNA amplicon sequencing to evaluate alpha and beta diversity. Inoculation with ITTG-R7^T significantly improved plant height, stem width, and plant dry weight, while ITTG-S70^T enhanced stem width and chlorophyll content. ACO-34A inoculation notably increased fruit number, size, and yield parameters. Moreover, inoculated plants exhibited reduced Fe and Cu accumulation compared to non-inoculated controls. Metagenomic analyses indicated that rhizobial inoculation did not significantly disrupt the native rhizosphere bacterial community. These findings highlight the potential of rhizobial strains as effective plant probiotics that enhance tomato productivity while preserving microbial community structure, supporting the integration of microbial biofertilizers into conventional farming systems. Full article

The blood orange arose from the insertion of a retrotransposon adjacent to the Ruby gene, an MYB-type transcriptional activator of anthocyanin production, as reported previously. However, the intricate process of anthocyanin regulation among different varieties of blood orange remains incompletely understood. In this study, mRNA levels of the transcription factors Ruby and TT8 were found to be upregulated in the juice vesicle tissues of a variety with higher concentrations of anthocyanins in the pulp compared with another variety with a lower anthocyanin content. In contrast, comparative analysis of the two varieties using two-dimensional electrophoresis and mass spectrometry did not identify differentially expressed proteins related to anthocyanin biosynthesis in the juice vesicle tissues. Furthermore, higher anthocyanin contents were observed in various tissues of transgenic Arabidopsis thaliana overexpressing the Ruby gene from blood orange compared with the wildtype plant. Moreover, the long terminal repeat (LTR) region of a retrotransposon inserted upstream of the Ruby locus exhibited the ability to drive reporter expression through histochemical assay in a transgenic seedling. Thus, a PCR-based molecular marker was developed, targeting the upstream sequence of the Ruby locus to identify Citrus hybrids with the unique trait of red-fleshed fruit. Intriguingly, bisulfite sequencing revealed differentially methylated regions within a Gag-Pol polyprotein-encoding sequence of a retrotransposon adjacent to Ruby locus when comparing two varieties with different anthocyanin contents. A higher average level of methylation status was observed in the fruit with a lower anthocyanin content. In conclusion, methylation modifications at specific upstream positions on the Ruby locus may influence anthocyanin production in blood oranges. Full article

Plant pruning is the selective removal of specific plant parts to enhance growth, shape, and health. In this work, the effects of pruning were evaluated regarding the physiological parameters, maturity, quality, and harvest indices and the nutritional quality features of twelve chayote [Sechium edule (Jacq.) Sw] (Cucurbitaceae) varieties. GC-FID approaches were utilized to determine CO₂ assimilation rates. The results demonstrated that pruning upregulated the leaf temperature and conductance but decreased transpiration and CO₂ assimilation rates within the evaluated period (06:30 a.m.–16:23 p.m.). It was noted that the implementation of pruning also impacted samples with enhanced photosynthetically active radiation activity, with a positive correlation with CO₂ assimilation. The macro- and micronutrient content was higher in samples with an epidermis, especially for S. edule var. albus spinosum. Nevertheless, the analyzed samples presented low (5–10 mL CO₂ kg⁻¹ h⁻¹), medium (10–15 mL CO₂ kg⁻¹ h⁻¹), and high levels (15–20 mL CO₂ kg⁻¹ h⁻¹) of respiratory intensity and weight loss (7–17%)—effects attributed to botanical differences between the studied chayote varieties. This work demonstrates, for the first time, the effects of pruning in chayote orchards and expands the knowledge regarding the implementation of effective approaches to produce plants with culinary, cultural, and medicinal implications. Further approaches are required to determine the effects of pruning on chayote after harvest. Full article

Lycium barbarum is a traditional medicinal and edible plant species in China, exhibiting notable salt tolerance that enables cultivation in salt-affected soils. However, intensifying soil salinization has rendered severe salt stress a critical limiting factor for its fruit yield and quality. Universal stress proteins (USPs) serve as crucial regulators for plant abiotic stress responses through developmental process modulation. Nevertheless, the characteristics and functional divergence of USP gene family members remain unexplored in L. barbarum. Here, we performed genome-wide identification and characterization of the USP gene family in L. barbarum, revealing 52 members unevenly distributed across all 12 chromosomes. Phylogenetic analysis classified these LbUSP members into four distinct groups, demonstrating the integration of the conserved USP domain and diverse motifs within each group. Collinearity analysis indicated a stronger synteny of LbUSPs with orthologs in Solanum lycopersicum than with other species (Arabidopsis thaliana, Vitis vinifera, and Oryza sativa), demonstrating that gene duplication coupled with functional conservation represented the primary mechanism underlying USP family expansion in L. barbarum. In silico promoter screening detected abundant cis-acting elements associated with abiotic/biotic stress responses (MYB and MYC binding sites), phytohormone regulation (ABRE motif), and growth/development processes (Box-4 and G-box). Transcriptome sequencing and RT-qPCR validation revealed tissue-specific differential expression patterns of LbUSP8, LbUSP11, LbUSP12, LbUSP23, and LbUSP25 in roots and stems under salt stress, identifying them as prime candidates for mediating salt resistance in L. barbarum. Our findings establish a foundation for the functional characterization of LbUSPs and molecular breeding of salt-tolerant L. barbarum cultivars. Full article

The WRKY gene family is a widely distributed and highly conserved transcription factor (TF) family in plants, with its members playing key roles in plant growth and development, stress response, and metabolism. Although WRKY TFs have been extensively studied in many plant species, research on the WRKY gene family in Vaccinium bracteatum Thunb. remains limited. Therefore, integrating molecular biology and bioinformatics approaches to further explore the WRKY gene family in V. bracteatum is of considerable scientific importance. In this study, we employed various online tools to obtain genomic and expression data, which were subsequently analyzed to determine the composition, evolutionary relationships, and functions of WRKY family genes in V. bracteatum. A total of 66 WRKY genes (VaWRKY) were identified, named based on homology alignment. Phylogenetic analysis classified the 66 VaWRKYs into three major clades and seven subclades. Sequence and structural analyses of VaWRKY genes provided insights into their evolutionary and functional characteristics. Expression profile analysis revealed significant differences in the expression of 12 VaWRKY genes at various stages of fruit development. Protein interaction analysis further indicated that VaWRKY genes are functionally diverse, playing important roles in stress response, seed germination regulation, and plant growth and development. In summary, we have a deeper understanding of VaWRKY genes, and systematic analysis of structure, evolutionary characteristics, and expression patterns plays an important role in analyzing its biological functions, molecular breeding, and enhancing economic value. Full article

Walnut septa, traditionally discarded as waste in walnut processing because they primarily serve a structural function in the walnut fruit, have recently gained attention for their potential abundance of phenolic compounds, suggesting their overlooked value. This study aimed to optimise extraction parameters to maximise the extraction yield of bioactive compounds and explore regional variations in antioxidant activity and chemical composition of Juglans regia L. septa. The experimental variables included extraction methods (maceration, dynamic maceration, ultrasound processing, and reflux extraction), temperature, solvent type (methanol, acetone, and ethanol), and the percentage of water in the solvent. The optimal conditions were determined based on the total phenolic content—reflux extraction using 60% ethanol as a solvent for a duration of 60 min. Samples from 12 different regions in Lithuania, Armenia, and Ukraine were analysed for their phenolic and proanthocyanidin content and antioxidant activity using the CUPRAC method. The total phenolic content ranged from 131.55 to 530.92 mg of gallic acid equivalents per g of dry weight of plant material (mg GAE/g dw), while the proanthocyanidin content varied from 1.14 to 7.65 mg of (–)-epicatechin equivalents per g dry weight of plant material (mg EE/g dw). Among all the regions studied, the Šiauliai sample demonstrated the highest concentrations of phenolic compounds, proanthocyanidins, and antioxidant activity, with statistically significant differences compared to the other samples (p < 0.05). These findings demonstrate that walnut septa are a valuable source of phenolic compounds and antioxidants, with significant potential for developing natural nutraceuticals and antioxidant products. Full article

Plant density influences interspecific interactions such as pollination and herbivory. In denser populations, pollinators find flowers more easily, increasing reproductive success and population growth. However, the same floral attractiveness also favors floral herbivory, a relationship described by Janzen and Connell as negative density dependence, considered an important mechanism for maintaining tropical diversity. This study analyzed the reproduction of Peixotoa tomentosa A. Juss. (Malpighiaceae) and Byrsonima intermedia A. Juss. (Malpighiaceae), considering population density and its influence on pollinator and herbivore attraction. The central hypothesis was that density affects fruit production. We conducted two treatments with both species: high density and low density in a preserved Brazilian savanna. We investigated fruit production, reproductive system, floral visitation rates, and the florivory rates of each species on each treatment. Our results showed that fruiting increased with density in both species. Peixotoa tomentosa is an agamospermous species, while B. intermedia is self-incompatible and relies exclusively on pollinators. Bees visited only B. intermedia, and the high-density treatment received more visits. Herbivores attacked more isolated P. tomentosa flowers. We concluded that density influences both pollination and herbivory, affecting plant reproduction, with effects mediated by the plant’s attractiveness in denser populations and by the size and quantity of flowers in single individuals. Full article