Search Results (518)

The Fruit-Weight 2.2-Like (FWL) gene family plays crucial roles in determining organ size and stress responsiveness in plants. However, the FWL family members remain largely unexplored in Gossypium species. In this study, we identified and characterized the FWL family in Gossypium hirsutum to investigate their gene expansion, functional evolution, and potential association with key agronomic traits. A total of 51 GhFWLs were identified, and their gene structures, domain compositions, and phylogenetic relationships were comprehensively analyzed. Expression profiling under heat, cold, salt, and drought stress conditions revealed that most GhFWLs participate in abiotic stress response pathways. Haplotype-based association analysis revealed significant associations for 14 GhFWLs with fiber-related traits, suggesting their potential functions in regulating fiber development. Furthermore, silencing the family member GhMCA1 provided supporting evidence for its role in salt stress tolerance. Our findings provided insightful information about the FWL gene family in G. hirsutum and highlighted candidate genes for improving fiber-related traits and stress tolerance through molecular breeding approaches. Full article

In arid and semi-arid regions, salinity and drought limit cotton productivity. As the northernmost cotton-growing country, Kazakhstan often deals with these issues. The objective of this study was to classify salt- and drought-tolerant groups within the Kazakhstan cotton collection based on key phenotypic traits. Fifty-six Gossypium hirsutum genotypes were evaluated under controlled conditions using NaCl and PEG-6000. Six morphophysiological traits, including germination rate, plant height, fresh weight, root dry weight, and relative water content, were analyzed. Increasing NaCl and PEG levels reduced vegetative growth, while germination remained relatively stable under moderate stress. Regression analysis identified 200 mM NaCl as the optimal salinity level for salt tolerance and 20–30% PEG as the optimal level for drought tolerance. Cluster analysis using membership function values grouped the genotypes into five tolerance categories. Eight lines including M-4016-6, M-4031-8, M-4014-6, M-4029-9, M-4016-7, M-4016-8, M-4020-2, and M-4016-4 exhibited high tolerance to both stresses. Additional lines exhibited combined tolerance, indicating strong breeding potential. Principal component analysis revealed an inverse relationship between salt and drought tolerance, suggesting stress-specific adaptation. This study is the first to report on the development of a classification system for salt and drought tolerance in the Kazakhstan Cotton Collection. The results demonstrate substantial genetic variability and highlight the potential for developing cotton cultivars adapted environments prone to stress. Full article

Cotton (Gossypium spp.) is the world’s most important fiber crop for the textile industry. Drought stress can adversely affect cotton production and quality, particularly in arid and semi-arid regions. Biochar, produced from biomass through pyrolysis, has the potential to alleviate drought stress in cotton production through improving soil properties and enhancing plant nutrition. The objectives of this study were to evaluate the effects of biochar produced from southern yellow pine (Pinus spp.) on cotton seedling emergence and growth, yield and its component traits, and fiber quality traits under field drought-stressed, arid conditions in the U.S. over two years. Six genotypes were evaluated in 2024, and three of these genotypes were evaluated following a single application of biochar at four rates (0, 6.25, 12.5, and 25.0 t ha⁻¹) applied at the beginning of the study. Significant genotypic differences were observed in both years, as expected. No genotype × biochar interaction was detected, indicating that different cotton genotypes responded similarly to biochar application. Groundcherry (Physalis acutifolia) infestation was unexpectedly higher, and cotton seedling growth was reduced in the biochar-amended plots compared with the non-biochar control in 2024, but these effects were not observed in 2025. Plots amended with 12.5 and 25.0 t ha⁻¹ biochar had significantly higher soil moisture than those receiving 0 or 6.25 t ha⁻¹ biochar. Estimated seedcotton yield was the highest in plots receiving 12.5 t ha⁻¹ biochar in both years and was significantly greater than that of the non-biochar control, with 18.3 and 8.4% increases in 2024 and 2025, respectively. Biochar had no significant effects on fiber length, uniformity, strength, elongation, and micronaire in either year, except that 6.25 and 12.5 t ha⁻¹ biochar rates increased elongation and 25.0 t ha⁻¹ biochar rate decreased micronaire. These results indicate a single biochar application had a positive, although diminishing, effect of biochar on cotton productivity during the first two years under drought stress, while having little to no effects on fiber quality. Full article

Alternating brackish–freshwater irrigation is a promising strategy for improving the utilization of marginal water resources in arid cotton (Gossypium hirsutum L.) production; however, its effectiveness is often limited by salt-induced physicochemical stresses, including sodium-induced soil structural degradation, osmotic stress, and reduced rhizosphere biological activity. This study investigated whether the combined application of microbial inoculant and polyacrylamide (PAM) could enhance root-zone functioning and plant performance under alternating brackish–freshwater irrigation. A controlled greenhouse pot experiment was conducted with five treatments, including conventional irrigation (CI), alternating irrigation (AI), AI combined with microbial inoculant (AI + B), AI combined with PAM (AI + PAM), and AI combined with microbial inoculant and PAM (AI + B + PAM). Soil water–salt conditions, physical properties, nutrient availability, microbial activity, root growth, and plant nutrient uptake were determined, and partial least squares path modeling (PLS-PM) was used to evaluate soil–root–plant interactions. Alternating irrigation reduced soil salinity and sodium accumulation compared with conventional irrigation, with electrical conductivity of the 1:5 soil–water extract (EC_1:5), Na⁺, and sodium adsorption ratio (SAR) decreasing by 14.68%, 16.21%, and 14.27%, respectively; under AI conditions, PAM increased water-stable aggregates by 22.54%, while microbial inoculant increased microbial biomass carbon by 33.47%. The combined AI + B + PAM treatment produced the greatest improvement in plant performance, increasing biomass, N uptake, P uptake, and K uptake by 28.79%, 47.37%, 48.00%, and 60.80%, respectively, compared with AI alone. PLS-PM supported a hypothesized pathway in which PAM-associated physical conditioning and microbial inoculant-mediated biochemical activation converged on root development, which was positively linked to nutrient acquisition and plant growth. These findings indicate that integrating microbial inoculant with PAM has potential to enhance root-zone resilience and cotton growth under alternating brackish–freshwater irrigation conditions, providing insights for the development of amendment strategies in saline soils. Further field validation is required before broader agricultural application. Full article

Film-mulched drip irrigation (FMDI) is used increasingly for cotton (Gossypium hirsutum L.) production in arid regions. However, salts often accumulate in the soil, eventually leading to soil salinization and crop failure when using FMDI with brackish water inappropriately. Evaluation of the leaching requirement (LR) for cotton under FMDI with brackish water that comprehensively considers cotton yield, water saving, soil conditions, and economic benefits needs to be investigated more completely. The present study compared the cotton growth for different leaching fractions (LF) under FMDI with brackish water and provides comprehensive analysis of LR for cotton and its relationships with soil conditions. A higher LF was related to a lower cotton yield when the LF was larger than 0.15. Moreover, a larger LF led to a lower ratio of reproductive growth and irrigation water productivity when the LF was larger than 0.2. A high soil water content (SWC) strip was observed in the 40–60 cm soil layers for all scenarios. Moreover, a higher SWC proportion in the deeper soil layers as for LF_0.15 or LF_0.2 may also be beneficial to cotton growth. Soil salinity decreased with decreases in irrigation water quantity when the LF was lower than 0.2, but increased when the LF was higher than 0.2. Either too much or too little irrigation water was not beneficial from an economic perspective. Our study indicated that the LR values between 0.05 and 0.15 were recommended for FMDI when the total dissolved solids for brackish water is within 1.61–3.21 g L⁻¹. Integrated strategies, including optimized irrigation-fertilizer management, groundwater depth monitoring, and halophyte intercropping, are required to sustain production while mitigating secondary salinization and groundwater pollution under FMDI with brackish water. Full article

Pyruvate kinase (PK) is the terminal rate-limiting enzyme of glycolysis and occupies a central position in plant energy metabolism and carbon skeleton allocation. Plant PK isoenzymes comprise the cytosolic pyruvate kinase (PKc) and the plastidic pyruvate kinase (PKp), which differ markedly in gene origin, protein structure, subcellular localization, and physiological function, exhibiting independent evolutionary histories and functional diversification. Recent studies have revealed that PKc possesses dynamic subcellular distribution, allowing it to shuttle among the cytosol, mitochondria, and nucleus, where it participates in stress responses and epigenetic regulation through protein–protein interactions. PKp is localized to plastids and connects carbon metabolism with lipid biosynthesis and the methylerythritol phosphate (MEP) pathway by supplying pyruvate, thereby playing critical roles in seed development and oil accumulation. This review comprehensively summarizes recent advances in plant PKc and PKp concerning protein structure and subunit composition, tissue-specific expression, subcellular localization, protein interaction networks, activity regulation, and their effects on plant growth, development, and stress responses. In addition, phylogenetic tree, motif, and domain analyses of pyruvate kinase genes from Oryza sativa (rice), Glycine max (soybean), Gossypium hirsutum (cotton), Solanum tuberosum (potato), Arachis hypogaea (peanut), and Arabidopsis thaliana, as well as promoter cis-element analyses, are performed. This review aims to provide theoretical references for crop quality improvement and stress-resilient breeding. Full article

Background/Objectives: Soil salinization constitutes a critical threat to global agriculture, with cotton (Gossypium spp.) being highly susceptible. This abiotic stress most severely impacts cotton during the early sowing and seedling stages, compromising stand establishment and early growth. Manifestations of this stress include reduced germination rates, uneven emergence, stunted seedlings, and, ultimately, diminished boll set and fiber yield. Methods: To investigate the molecular basis of salt tolerance in cotton seed germination, we performed integrated transcriptomic and metabolomic profiling of Gossypium hirsutum cv. ST022-1056m5 under 150 mM NaCl stress at 24 h, 48 h, and 72 h, finding that salt stress significantly inhibited germination. Differentially expressed genes (DEGs) and differentially accumulated metabolites (DAMs) were identified, followed by functional enrichment and Weighted Gene Co-expression Network Analysis (WGCNA) to construct regulatory networks. Results: Transcriptomics revealed stage-specific differentially expressed genes, with predominant downregulation and enrichment in catalytic/transporter activities. Metabolomics showed distinct reprogramming, with 210 shared differentially accumulated metabolites enriched in lipids, organic acids, terpenoids, and phenolic acids. KEGG analysis highlighted time-dependent pathway shifts: sucrose metabolism and MAPK signaling at 24 h, photosynthesis at 48 h, and cuticular lipid biosynthesis at 72 h. Weighted Gene Co-expression Network Analysis (WGCNA) identified stage-associated modules and hub genes (GH_A02G0892, GH_A08G2853), and multi-omics integration indicated the strongest transcript–metabolite coordination at 24 h. Conclusion: Our study reveals dynamic molecular reprogramming underpinning stage-specific salt adaptation in germinating cotton seeds. These identified DEGs, DAMs, and hub genes represent promising candidate targets for molecular breeding and offer a crucial genetic basis for improving salt tolerance in cotton. Full article

Background: Upland cotton (Gossypium hirsutum) is a major natural fiber crop and an important model for studying genome evolution and gene function in polyploid plants. However, its large and highly redundant genome presents substantial challenges for efficient and coordinated multiplex genome editing. Methods: Here, we developed a high-efficiency CRISPR/Cas12a-based multiplex genome editing system in cotton by integrating a tRNA–crRNA polycistronic expression strategy with a Bean yellow dwarf virus (BeYDV)-derived replicon. Results: This platform enabled coordinated expression of multiple crRNAs and simultaneous targeting of 16 loci within a centromere-proximal region of chromosome D03 (18.65–24.47 Mb). In individual transgenic lines, up to 10 target sites were edited concurrently, with nine targets exhibiting editing efficiencies above 56% and the highest efficiency reaching 96.46%. High-density multiplex editing predominantly induced small insertions and deletions at target loci. Notably, edited plants exhibited reduced growth and pronounced cytological abnormalities, including chromosome bridges, lagging chromosomes, and abnormal meiotic products. Transcriptome analysis revealed widespread dysregulation of genes involved in chromosome segregation and cell cycle regulation. Despite these functional perturbations, HiFi long-read sequencing detected no large-scale chromosomal rearrangements, indicating that genome instability arises from cumulative local perturbations rather than global structural alterations. Conclusions: Together, our results establish an efficient multiplex genome editing platform in cotton and highlight potential constraints of high-density editing on genome stability in complex plant genomes. Full article

Cotton is recognized as the primary source of essential natural fibers for the global textile industry, supporting its sustainability and development. However, adverse environmental conditions such as drought severely constrain cotton production; thus, developing stress-tolerant cultivars via molecular breeding is essential for maintaining yield stability. Here, a comprehensive functional dissection was conducted on GhGA2ox15, a gibberellin 2-oxidase gene derived from Gossypium hirsutum L. This gene encodes a key catabolic enzyme implicated in the deactivation of endogenous bioactive GAs and the modulation of stress adaptation. We characterized GhGA2ox15, a GA2ox gene from upland cotton that modulates endogenous bioactive GA levels and abiotic stress tolerance. Bioinformatics and sequence analyses confirmed that GhGA2ox15 is a canonical C₂₀-GA2ox subfamily member, with conserved DIOX_N and 2OG-FeII_Oxy domains and marked similarity to orthologs in Arabidopsis and rice. Tobacco subcellular localization assays indicated that GhGA2ox15 resides in both the nucleus and the cytoplasm. In transgenic Arabidopsis and Oryza sativa lines, GhGA2ox15 overexpression was shown to increase drought tolerance, while virus-induced gene silencing (VIGS) of GhGA2ox15 yielded significantly compromised drought resistance. Physiological assays linked GhGA2ox15 silencing to impaired reactive oxygen species (ROS) detoxification. The suppressed lines displayed markedly lower antioxidant enzyme activities, concomitant ROS accumulation in leaves, and attenuated transcription of drought-responsive marker genes. Our findings delineate the mechanistic role of GhGA2ox15 in drought adaptation and highlight its potential utility in breeding drought-tolerant cotton. Full article

In this study, we performed the first genome-wide identification and characterization of the cinnamoyl-CoA reductase (CCR) gene family in upland cotton (Gossypium hirsutum), focusing on its potential association with stem strength. We identified 76 GhCCR genes and classified them into four subfamilies. We then analyzed their evolutionary relationships, conserved domains, synteny, promoter cis-elements, and expression patterns. All GhCCR proteins possess the NADB_Rossmann superfamily domain, and family expansion appears to have been driven mainly by segmental and tandem duplications. A small number of GhCCR genes showed relatively high expression in leaf, pistil, and torus tissues, while genes such as GhCCR3/9/10 exhibited elevated transcript levels under abiotic stress conditions. RT-qPCR results indicated that three candidate GhCCR genes (GhCCR25, GhCCR52 and GhCCR64) were significantly more highly expressed in multiple tissues of the stiff-stem line JY-25 than in the soft-stem line JR-15. Together, these findings suggest that GhCCR genes may contribute to the regulation of growth, development, and stress adaptation in G. hirsutum. However, direct biochemical or genetic validation is required to confirm their functional roles in lignin biosynthesis and stem rigidity. Full article

(1) Background: Nitric oxide (NO) serves as a crucial signaling molecule in plant abiotic stress responses. Although its role in enhancing drought resistance in cotton has been recognized, the specific mechanisms underlying this physiological and molecular regulation remain largely unexplored. This study aims to elucidate the multi-layered mechanisms by which NO modulates drought resistance in cotton; (2) Methods: Cotton seedlings were subjected to drought stress with the application of the NO donor sodium nitroprusside (SNP). A combination of confocal laser scanning microscopy, transcriptional expression analysis, biochemical assay of enzyme activity, virus-induced gene silencing (VIGS), and in vitro protein modification assays was applied to characterize the effects of NO on the drought stress response in cotton; (3) Results: Exogenous NO significantly reinforced drought resistance in cotton seedlings by improving leaf water retention capacity and photosynthetic efficiency, eliminating excessive drought-induced reactive oxygen species (ROS), upregulating the transcription and enzymatic activity of antioxidant enzymes, and promoting stomatal closure. Mechanistically, NO triggered S-nitrosylation of the plasma membrane H⁺-ATPase isoform GhHA2, thereby enhancing its protein stability; (4) Conclusions: These findings reveal that exogenous NO orchestrates cotton drought tolerance via multiple interconnected physiological and molecular pathways, in which the activation of the antioxidant defense system and the modulation of stomatal closure serve as central regulatory mechanisms. Full article

Polyamines, a class of low-molecular-weight nitrogen-containing bases with high biological activity, are ubiquitous in organisms and play protective roles in plants under stress. Polyamine oxidase (PAO), a typical flavoprotein characterized as a glycoprotein, is a key enzyme in polyamine catabolism that directly mediates polyamine breakdown and maintains intracellular polyamine homeostasis. However, the specific functions of PAOs in cotton fiber development remain largely unclear. In this study, we identified 23 GhPAO genes from the upland cotton (Gossypium hirsutum L.) genome via comprehensive bioinformatics approaches. We systematically analyzed their physicochemical properties, phylogenetic relationships, gene structures, chromosomal locations, conserved motifs, cis-acting elements, and expression patterns. Quantitative real-time PCR (qPCR) analysis confirmed that GhPAO10 and GhPAO21 exhibited the most pronounced transcript accumulation during both fiber development and stress response processes. Further yeast one-hybrid (Y1H) and dual-luciferase reporter assays indicated that the GhPAO21 promoter was directly regulated by the transcription factor GhTGA1. Our findings provide a foundation for elucidating the functional roles of the PAO gene family in upland cotton and underscore potential candidate genes associated with fiber development and stress responses. Full article

Cotton (Gossypium hirsutum L.) is a promising candidate for an Arsenic (As)-tolerant plant due to its low As accumulation in fibers. The individual arbuscular mycorrhizal fungi (AMF) inoculation or exogenous calcium (Ca²⁺) application is known to enhance heavy metal tolerance in higher plants; however, their synergistic mechanisms in alleviating As stress in cotton remain poorly understood. A three-factor pot experiment was conducted, including two levels of AMF (Funneliformis mosseae C.Walker & A.Schüßler) inoculation (non-inoculated/inoculated), As stress (0/100 mgAs⁵⁺·kg⁻¹soil), and exogenous Ca²⁺ (CaCl₂) application (0/20 mmol·L⁻¹ CaCl₂). AMF inoculation and Ca²⁺ application were investigated for their effects on cotton growth, root morphology, photosynthetic characteristics, osmotic regulators, antioxidant enzyme activities, and ion homeostasis under As stress. Results showed As stress significantly disrupted cotton growth (decreased plant height, shoot and root dry weight) and root morphology (reduced total root length, root area, and root fork number), photosynthetic capacity (reduced Pn, Ci, Fv/Fm, and ΦPSII), osmotic adjustment (decreased proline, soluble sugar and protein), antioxidant defense (inhibited SOD, POD, CAT activities), and K⁺/Ca²⁺ homeostasis (reduced concentration of K⁺ and Ca²⁺, and K⁺/Ca²⁺ ratio). Both AMF inoculation and Ca²⁺ application independently alleviated these adverse effects of As stress. At the same time, AMF symbiosis combined with exogenous Ca²⁺ was better than AMF inoculation or Ca²⁺ application alone in optimizing root architecture, improving stomatal function and photosynthetic efficiency, enhancing osmotic regulator accumulation and antioxidant enzyme activities, and restoring ion balance under As stress. Three-way ANOVA confirmed significant As×AMF×Ca²⁺ interactions on key parameters such as Pn and ΦPSII. In summary, both AMF inoculation and Ca²⁺ application synergistically enhanced cotton As tolerance through regulating growth, root morphology, photosynthetic characteristics, osmotic regulators, antioxidant enzyme activities, and ion homeostasis, demonstrating its potential for sustainable cotton cultivation in As-contaminated soils. Full article

Cotton, as a globally significant economic crop, is intricately regulated in its growth and development by the key genes for SA (Salicylic acid) biosynthesis. In the present study, a systematic analysis of genes related to SA biosynthesis was conducted across four cotton species, leading to the identification of 70 genes. Specifically, the tetraploid species Gossypium hirsutum and G. barbadense were found to harbor 22 and 23 genes, respectively, representing a substantial expansion compared to the 12 and 13 genes identified in the diploid progenitors G. arboreum and G. raimondii. Comprehensive characterization of chromosomal localization, phylogeny, domain architecture, and promoter cis-elements revealed a uniform distribution of key genes involved in SA biosynthesis across A/D sub-genomes of tetraploids with extensive interspecific collinearity; whole-genome and segmental duplication act as the dominant drivers for the expansion of this gene family, while partial gene loss following polyploidization results in non-doubled gene copy numbers in tetraploids relative to diploids, which reflects the evolutionary selection for genomic dosage balance. The key genes for SA biosynthesis demonstrate a high degree of conservation in protein sequences, protein structures, and conserved motifs, which constitute the structural basis for the stable maintenance of their core functions in the SA biosynthesis pathway during plant evolution. This is closely related to their core function in the salicylic acid (SA) synthesis pathway and serves as the structural basis for the stable maintenance of gene functions during evolution. Analysis of cis-elements revealed that the expression of key genes involved in SA biosynthesis is governed by a complex interplay of phytohormones, stress signals, and transcription factors. Yeast one-hybrid (Y1H) assays confirmed the interaction between the GhPAL and GhICS gene and predicted candidate transcription factors, specifically the binding of GhWRKY21 to GhICS2-1 promoter and GhMYB12 to GhPAL1-2 promoter, thus elucidating their stage-specific regulatory mechanisms in cotton fiber development and reflecting their evolution. This study provides a fundamental basis for investigating the role of the SA signaling pathway in cotton development and offers support for cotton molecular breeding. Full article

The clover cutworm, Anarta trifolii (Lepidoptera: Noctuidae), constitutes a polyphagous pest known for causing sporadic, local outbreaks that significantly damage Beta vulgaris, Gossypium hirsutum, Brassica oleracea and others. Evidence supports the occurrence of seasonal migration in this species, but the determinants of A. trifolii flight performance remain unexplored. Understanding the species’ flight performance is essential for predicting its long-distance dispersal, identifying source and sink populations, and improving regional pest forecasting. We characterized flight performance and its influencing factors via computer-monitored flight mills. Maximum flight performance was achieved in A. trifolii adults at two days, followed by a significant decline with increasing age. At 24 °C and 80% relative humidity (RH), in a 12 h test, males and females aged two days achieved total flight distances of 38.90 ± 1.21 km and 31.70 ± 1.56 km, respectively. In a 24 h test, three-day-old adults reached a maximum flight speed of 19.68 km/h, a sustained flight duration of 17.38 h, a total flight duration of 23.89 h, a sustained flight distance of 69.64 km, and a total flight distance of 96.56 km. The flight performance of A. trifolii was significantly affected by both temperature and RH, with the maximum flight capacity achieved at 18–28 °C and 35–80% RH. Flight performance was significantly enhanced when A. trifolii were fed honey or sucrose. Moreover, the wingbeat frequency of A. trifolii adults varied among age groups, ranging from 31.90 to 57.65 Hz. In females, the wingbeat frequency peaked at 2 days old (46.72 ± 0.25 Hz), whereas in males it peaked at 10 days old (47.18 ± 0.66 Hz). These results advance the fundamental understanding of A. trifolii migration and offer practical applications, including improved pest management strategies, optimized use of chemical insecticides and biological control agents, and enhanced decision-making in integrated pest management programs. Full article