Search Results (253)

Cotton is a vital economic crop, and cotton fiber serves as the primary raw material for the textile industry. Lignin in cotton fiber is closely associated with fiber quality. Lignin is synthesized through the phenylpropanoid metabolic pathway, where the cinnamyl alcohol dehydrogenase gene CAD6 plays a significant role. In this study, we obtained successfully transformed overexpression plants by constructing an overexpression vector and performing genetic transformation and tissue culture. To verify the function of the GhCAD6 gene in upland cotton, we analyzed the agronomic traits, fiber quality, cell wall structure, and lignin content of GhCAD6-overexpressing plants. Our results indicate that the GhCAD6 gene is predominantly expressed during the stages of fiber elongation and secondary wall synthesis. Overexpression of the GhCAD6 gene resulted in increased plant lignin content and fiber upper half mean length, boll number per plant, fiber uniformity index, strength, and lint were improved. The fiber surface was smoother, and the fiber cell wall was more compact. These findings demonstrate that the GhCAD6 gene positively regulates lignin synthesis and fiber quality formation, contributing to the enhancement of cotton fiber quality. Full article

Effective residue management is crucial for maintaining soil organic carbon (SOC) in upland rice systems, particularly under diverse fertilization and planting management practices. This study investigates the impacts of residue management in upland rice fields using the CQESTR model through simulation of SOC dynamics over a 20-year period. The first 10 years served as a spin-up period for carbon pool stabilization in the model, followed by simulations under varying nitrogen (N) application rates and planting date management strategies. Experiments for various N application rates and planting times were conducted during 2018–2019 and 2019–2020. In 2019, 30% and in 2020, 100% of the residue was returned, and these data were used for evaluating model performance. Subsequently, we modeled predictions for residue retention levels of 100%, 70%, 50%, and 30% to assess their effects on SOC. The results indicated a good agreement between the simulated and observed data for model performance evaluation with an MSD value of 9.13. Lack of correlation (0.44) accounted for 5% of MSD, indicating a good agreement between the simulated and observed SOC values. The highest change in SOC was observed at 100% residue return under moderately delayed planting, potentially due to higher crop productivity and residue retention, and moderate climatic conditions. Reduced residue retention gradually declined the SOC stocks, especially under low N input. Delays in planting exacerbated negative impacts, possibly due to low crop productivity and reduced residue return. Despite the limited number of years of data and inconsistent management practices, the overall trends highlight the importance of residue retention under different N fertilization and planting management strategies. This research serves as a preliminary study for sustainable management practices to enhance long-term soil carbon sequestration in upland rice systems in southern Thailand. Long-term evaluations are necessary using the observed data and the CQESTR model application for applicable recommendations. Full article

Extreme drought events may become more frequent with climate change. Understanding the impact of extreme drought on grassland ecosystems is therefore crucial for the long-term sustainability of ecosystems. Here, we identified extreme drought events in the Inner Mongolia grasslands of China using long-term standardized precipitation evapotranspiration index (SPEI) data and evaluated drought resistance of the vegetation under extreme drought based on net primary production (NPP). The impact of consecutive extreme drought events and multiple discontinuous one-year extreme drought events on grasslands were further analyzed to investigate the response strategies of different grassland types to different drought conditions. We found that the frequency and area of extreme drought in 2000–2011 were significantly higher than those in 2012–2020, and the Xilingol League region showed the highest frequency of extreme drought events. Under extreme drought, vegetation resistance was positively correlated, where annual precipitation > 300 mm. The mean resistance of different grassland types followed the order: upland meadow (UM) > lowland meadow (LM) > temperate meadow steppe (TMS) > temperate desert (TD) > temperate steppe (TS) > temperate steppe desert (TSD) > temperate desert steppe (TDS). In the analysis of two cases of consecutive two-year extreme drought, all grassland types except TSD and TD showed obvious decreased resistance in the final drought year, with the highest reduction (0.16) in LM during 2010–2011, implying the widespread and significant inhibition of grassland growth by continuous drought. However, under the multiple discontinuous extreme drought events, the resistance of all grassland types showed a fluctuating but an overall increasing trend, suggesting the adaptability of grassland to drought. The results emphasize that management departments should pay more attention to regions with low resistance and enhance the stability of grassland production by increasing the proportion of drought-resistant plants in reaction to future extreme drought scenarios. Full article

Cottonseeds, rich in high-quality protein and fatty acids, represent a vital plant-derived feedstuff and edible oil resource. To systematically investigate genetic variation patterns in nutritional quality and screen superior germplasm, this study analyzed 26 nutritional quality traits and 8 fiber traits across 259 upland cotton (Gossypium hirsutum L.) accessions using multivariate statistical approaches. Results revealed significant genetic diversity in cottonseed nutritional profiles, with coefficients of variation ranging from 3.42% to 26.37%. Moreover, with advancements in breeding periods, the contents of protein, amino acids, and the proportion of unsaturated fatty acids (UFAs) increased, while oil content and C16:0 levels decreased. Correlation analyses identified significant positive associations (p < 0.05) between proteins, amino acids, UFAs, and most fiber traits, except for seed index (SI), fiber micronaire (FM), and fiber elongation (FE). Through a principal component analysis–fuzzy membership function (PCA-FMF) model, 13 elite accessions (F > 0.75) with high protein content, high UFA proportion, and excellent fiber quality were identified. These findings provide both data-driven foundations and practical germplasm resources for value-added utilization of cottonseed and coordinated breeding for dual-quality traits of nutrition and fiber. Full article

As an important reserve resource for cultivated land, the improvement and fertility enhancement of saline-alkali land are key to alleviating the pressure on cultivated land and ensuring the sustainable utilization of land resources. Studying the regulatory effect of rotation patterns on the soil fertility of saline-alkali land is one of the core research contents in exploring low-cost and environmentally friendly comprehensive management strategies for saline-alkali land. This study focuses on Zhaoyuan County, a representative saline and alkaline area within the Songnen Plain. Utilizing remote sensing technology, crop information was systematically collected across 13 time periods spanning from 2008 to 2020. These data were employed to construct a comprehensive crop information change atlas. This atlas categorized crop rotation patterns based on crop combinations, rotation frequencies, and the number of consecutive years of planting. Using soil sampling data from 2008 and 2020, a soil fertility evaluation was conducted, and the changes in soil chemical properties and fertility under various crop rotation patterns were analyzed. The results of the study show that, during the study period, crop rotation patterns in Zhaoyuan County were dominated by paddy-upland rotations and upland crop rotations. Crop rotation patterns, categorized by crop combination, were dominated by soybean–maize–other crops rotation (S-M-O) and rice–soybean–maize–other crops rotation (R-S-M-O). The frequency of crop rotation is dominated by low- and medium-frequency crop rotation. Crop rotation significantly increased soil organic matter, total nitrogen content, and overall soil fertility in the study area, while simultaneously lowering soil pH levels. Crop rotation patterns with different crop combinations had significant effects on soil chemical properties, with smaller differences in the effects of different rotation frequencies and years of continuous cropping. Crop rotation patterns incorporating soybean demonstrate a significant positive regulatory impact on the soil fertility of saline-alkali land. Low-frequency crop rotation (with ≤5 crop changes) has a relatively better effect on improving soil fertility. This research provides important empirical support and decision-making references for establishing sustainable farming systems in ecologically fragile saline-alkali areas, ensuring regional food security, and promoting the long-term sustainable utilization of land resources. Full article

Oil sands mining in northeastern Alberta, Canada, has disturbed large areas of the northern boreal forest which must be restored to pre-disturbance levels through reclamation. The oil sands tailings have high pH and elevated levels of Na⁺ which are harmful to plants. A novel non-segregating tailing (NST) was developed to accelerate consolidation of fine tailings, yet its effects on boreal plant species are not well characterized. In oil sands reclamation, a capping layer—either forest mineral soil mix (FMM), salvaged from upland boreal forest sites, or peat mineral mix (PMM), sourced from peatlands—is typically applied over overburden materials and coarse tailings sands prior to revegetation. Plants in oil sands revegetation sites frequently experience nutrient deficiencies, such as nitrogen and phosphorus, and impaired physiological processes due to the high pH and soil salinity. In this study, we examined the effects of nitrogen and phosphorus supplements in the NST-amended reclamation soils on growth and physiological parameters of trembling aspen (Populus tremuloides) and white spruce (Picea glauca) seedlings. We found that the growth and physiological responses of seedlings were superior in the mixture of NST and FMM compared with NST and PMM. Phytotoxicity of NST was associated with elevated boron levels. Trembling aspen exhibited greater sensitivity to NST but showed stronger growth improvements with increased nitrogen and phosphorus supplementation compared to white spruce. High levels of nitrogen and phosphorus supplementation alleviated the adverse effects on both species that were caused by mineral nutrient imbalance. Full article

Fibrillins (FBNs) are indispensable for plant growth and development, orchestrating multiple physiological processes. However, the precise functional role of FBNs in cotton fiber development remains uncharacterized. This study reports a genome-wide characterization of the FBN gene family in cotton. A total of 28 GhFBN genes were identified in upland cotton, with systematic analyses of their phylogenetic relationships, protein motifs, gene structures, and hormone-responsive cis-regulatory elements. Expression profiling of GhFBN1A during fiber development revealed stage-specific activity across the developmental continuum. Transcriptomic analyses following hormone treatments demonstrated upregulation of GhFBN family members, implicating their involvement in hormone-mediated regulatory networks governing fiber cell development. Collectively, this work presents a detailed molecular characterization of cotton GhFBNs and establishes a theoretical foundation for exploring their potential applications in cotton breeding programs aimed at improving fiber quality. Full article

Background: Gossypium hirsutum L. is one of the main economic crops worldwide, and increasing the size/weight of its seeds is a potential strategy to improve its seed-related yield. AINTEGUMENTA (ANT) is an organogenesis transcription factor mediating cell proliferation and expansion in Arabidopsis, but little is known about its candidate function in upland cotton seed. Results: In this study, functional characterization of GhANT in the cotton seed development stage was performed. The expression pattern analysis showed that GhANT was predominantly expressed in the ovules, and its expression was consistent with the ovules’ development stage. Heterologous expression of GhANT in Arabidopsis promoted plant organ growth and led to larger seeds. Importantly, specific expression of GhANT by the TFM7 promoter in the cotton ovules enlarged the seeds and increased the cotton seed yield, as compared with the wild-type in a three-year field trial. Furthermore, transcription level analysis showed that numerous genes involved in cell division were up-regulated in the ovules of TFM7::GhANT lines in comparison to the wild-type. These results indicate that GhANT is a potential genetic resource for improving cotton seed yield through its molecular links with cell cycle controllers. Full article

Background: The B3-domain transcription factor ABI3 (ABSCISIC ACID INSENSITIVE 3) is a critical regulator of seed maturation, stress adaptation, and hormonal signaling in plants. However, its evolutionary dynamics and functional roles in cotton (Gossypium spp.) remain poorly characterized. Methods: We conducted a comprehensive genome-wide investigation of the ABI3 gene family across 26 plant species, with a focus on 8 Gossypium species. Analyses included phylogenetics, chromosomal localization, synteny assessment, gene duplication patterns, protein domain characterization, promoter cis-regulatory element identification, and tissue-specific/spatiotemporal expression profiling under different organizations of Gossypium hirsutum. Results: Phylogenetic and chromosomal analyses revealed conserved ABI3 evolutionary patterns between monocots and dicots, alongside lineage-specific expansion events within Gossypium spp. Syntenic relationships and duplication analysis in G. hirsutum (upland cotton) indicated retention of ancestral synteny blocks and functional diversification driven predominantly by segmental duplication. Structural characterization confirmed the presence of conserved B3 domains in all G. hirsutum ABI3 homologs. Promoter analysis identified key stress-responsive cis-elements, including ABA-responsive (ABRE), drought-responsive (MYB), and low-temperature-responsive (LTRE) motifs, suggesting a role in abiotic stress regulation. Expression profiling demonstrated significant tissue-specific transcriptional activity across roots, stems, leaves, and fiber developmental stages. Conclusions: This study addresses a significant knowledge gap by elucidating the evolution, structure, and stress-responsive expression profiles of the ABI3 gene family in cotton. It establishes a foundational framework for future functional validation and targeted genetic engineering strategies aimed at developing stress-resilient cotton cultivars with enhanced fiber quality. Full article

Bacterial blight (BB) disease is a serious stress that affects up to 80% of rice yield. Utilizing an elite resistant variety was previously thought to be an alternative way to control disease outbreaks. The indigenous upland rice variety ULR207 is a high-potential donor for the BB resistance breeding program. However, the quantitative trait loci (QTLs) associated with bacterial blight resistance in this variety have not yet been discovered. Therefore, QTLs associated with BB resistance need to be identified. In this study, we identified the QTLs associated with BB resistance in the F_2:3 population crossed between the BB resistance variety ULR207 and Maled Phai, as well as a susceptible variety, via QTL-seq analysis and bulk-segregant analysis. We found a new QTL-associated BB resistance locus (qBBchr8) mapped on chromosome 8. Five positions were candidates, including Os08g0110700, Os08g0115200, Os08g0131300, Os08g0139500, and Os08g0163900. Afterwards, Kompetitive Allele-Specific PCR (KASP) markers specific to the SNP variant and the position of each gene were designed. These markers, associated with the disease lesion length phenotype, were validated with another 178 individual plants of the F₂ population via single-marker analysis. This analysis revealed that the position Os08g0110700 was the strongest locus, with a PVE of 15.00%. The results suggest that this KASP SNP marker could be used to improve elite rice for BB resistance. Full article

Morkhor 60-3 is an upland rice variety primarily cultivated in northeastern Thailand. This glutinous rice is valued for its adaptability and rich aroma but remains susceptible to significant diseases, particularly blast and bacterial blight. Using resistant varieties represents the most cost-effective approach to address this limitation. This study incorporated the QTLs/genetic markers qBl1, qBl2, and xa5 from Morkhor 60-1 through marker-assisted backcrossing. From the BC₁F₃ population, ten lines were selected based on their parentage and evaluated for blast resistance using a spray inoculation method with 12 isolates of Pyricularia oryzae, and for bacterial blight (BB) resistance using a leaf-clipping method with nine isolates of Xanthomonas oryzae pv. oryzae. Broad-spectrum resistance (BSR) was also assessed in the lines for both diseases. Subsequently, BC₁F₄ lines were evaluated for field performance, including agronomic traits and aroma. Results identified three superior lines, BC₁F₄ 22-7-140-4, BC₁F₄ 22-7-322-5, and BC₁F₄ 22-7-311-9, that demonstrated resistance to both BB and blast pathogens with average BSR values of 0.61 and 1.00, 0.66 and 1.00, and 0.55 and 0.87, respectively. These lines also exhibited enhanced performance in flowering date, plant height, panicle number per plant, grain number per plant, and grain weight. These findings demonstrate the effectiveness of marker-assisted selection (MAS) for gene pyramiding in rice improvement. Full article

Excessive application of a chemical fertilizer during rice cultivation leads to soil infertility and increases production costs. An alternative way to reduce over-fertilization is to partially or fully replace the fertilizer with microbes that promote the growth and production of plants. This study aimed to investigate the Maled Phai rice cultivar (Oryza sativa L.) in a field experiment with two fungi strains. Rhizophagus variabilis KS-02 and Trichoderma zelobreve PBMP16 were selected as inocula and compared with non-R. variabilis KS-02 and non-T. zelobreve PBMP16, acting as controls, one without synthetic fertilizer and one with synthetic NPK fertilizer. The field experiment was conducted in a Randomized Complete Block design with four replications. Growth and yield parameters were determined in the plant tissues and roots, and bioactive compounds were determined in the rice seeds. The results show the presence of T. zelobreve PBMP16 and R. variabilis KS-02 colonization in the plant roots at the harvest stage. A single inoculum of both R. variabilis KS-02 and T. zelobreve PBMP16 significantly increased most of the plant growth performance and yield parameters, as well as the concentrations of bioactive compounds. Remarkably, such effects were more apparent than those observed with the use of a chemical fertilizer. Thus, a single inoculum of R. variabilis KS-02 or T. zelobreve PBMP16 and the co-inoculation of both have the potential to increase the grain yield and bioactive compounds of Maled Phai under field conditions. Full article

Phosphorus (P) is an essential nutrient for plant growth, and low-phosphorus (LP) stress significantly limits cotton productivity. Here, we conducted single- and multi-locus genome-wide association studies (GWASs) on four LP-related traits using 419 upland cotton (Gossypium hirsutum L.) accessions genotyped with 2.97 million single-nucleotide polymorphisms (SNPs). Phenotypic analysis reveals substantial variation under LP stress, with LP-SDW showing the highest coefficient of variation (33.69%). The GWASs identified thousands of significant SNPs, including pleiotropic loci associated with multiple traits. Chromosomes A08, D09, and D12 harbored novel associated signals. Multi-locus models significantly enhanced detection sensitivity, identifying 123 SNPs undetected by single-locus approaches. Functional annotations prioritized six candidate genes near associated SNPs, including GhM_A08G1315 (remorin protein) and GhM_D06G1152 (carotenoid cleavage dioxygenase), whose LP-induced expression patterns were validated by qRT-PCR. These genes are implicated in membrane signaling, root architecture modulation, and hormone metabolism. Our findings provide novel genetic insights into LP tolerance and establish a foundation for breeding phosphorus-efficient varieties through marker-assisted selection in cotton. Full article

Background: The GhA01EP1 gene in upland cotton encodes an epidermal-specific secreted glycoprotein, whose functional characterization remains unexplored beyond our initial discovery of its water deficit resistance association. Therefore, we further designed experiments to investigate the functional role of GhA01EP1. Methods: We sequenced and analyzed the transcriptomes of wild-type (Col-0) and GhA01EP1-transgenic Arabidopsis thaliana. The differences in morphological and biochemical indicators were examined. In addition, the proteins interacting with GhA01EP1 in Arabidopsis were screened using a glutathione-S-transferase pull-down assay. Results: The GhA01EP1-transgenic Arabidopsis plants flowered earlier, produced more branches, and had a higher seed yield than Col-0. Transcriptome analysis revealed that differentially expressed genes detected in the comparison of GhA01EP1-transgenic and Col-0 Arabidopsis under the water treatment (the control) were associated especially with circadian rhythm regulation, photoperiodic flowering reaction, hormone metabolism, glyoxalase I synthesis, antioxidant pathway, branching development, and carbon-nitrogen allocation. Under water-sufficient or water-deficient treatments, the glyoxalase I activity and lignin content of GhA01EP1-transgenic Arabidopsis were significantly higher. Under water deficit stress, the malondialdehyde and starch contents were significantly lower, while peroxidase activity and protein content were significantly higher than those of Col-0. Conclusions: GhA01EP1 synergistically improved the precocity, water deficit tolerance, and seed yield of GhA01EP1-transgenic Arabidopsis. Analysis of GhA01EP1 function provides a molecular basis for breeding improved cotton varieties. Full article

This study aims to reveal the genetic variation of fruit branch angle (FBA) in upland cotton, thereby providing a scientific basis and practical guidance for cotton architecture breeding. We explored the genetic variation pattern of FBA in 300 upland cottons from different regions and different periods, respectively. Cluster analysis and principal component analysis were used to comprehensively evaluate the plant architecture traits and yield traits in 300 upland cottons. The results demonstrated that the range of variation of FBA in cotton was 43.59–69.32°, the coefficient of variation ranged from 6.06% to 7.42%, and the broad-sense heritability was 75.50%. The order of FBA in different regions was as follows: Foreign Germplasm (FG; 56.77°) > Yellow River Region (YRR; 56.24°) > Yangtze River Region (YZRR; 56.16°) > Liaoning Special Maturing Region (LSMR; 55.35°) > Northwest Inland Region (NIR; 55.25), which is rich in genetic diversity. FBA in cotton in different periods had obvious differences. FBA was the largest before 1960, and as the period progressed, FBA showed an overall fluctuating decrease, whose coefficient of variation and genetic diversity index tended to increase. In this study, it was found that when the range of FBA was 50.46–55.31°, cotton had the best overall performance, with compact architecture, fewer empty fruit branches, more bells, and higher yield, which can be further developed and utilized as an excellent cotton germplasm resource. Full article