[Objective] To address the issues of idle field in winter and spring, low utilization efficiency of cotton straw, and declining profitability in cotton production in the Yellow River Basin, a cotton-Stropharia rugosoannulata double cropping system was proposed, which utilize crushed cotton straw for S. rugosoannulata cultivation in the winter fallow field, followed by S. rugosoannulata residue returning to field. The objective was to investigate the comprehensive effects of this system on productivity, economic benefit, and soil fertility, aiming to provide technical support for the green and sustainable development in the local cotton-growing region. [Methods] Field experiments were conducted from 2022 to 2024 in Linqing City, Shandong Province. Using monocropped spring cotton (MFC) and monocropped short-season cotton (MSC) as controls, the annual yield, economic returns, and soil nutrient content dynamics of two double cropping patterns, intercropping of spring cotton with S. rugosoannulata (FC+SR), short-season cotton followed by S. rugosoannulata in succession planting (SC+SR), were systematically compared. [Results] Compared with MFC treatment, the seed cotton yields of FC+SR and SC+SR treatments significantly decreased by 7.7% and 14.2%, respectively. However, by harvesting S. rugosoannulata (fresh yield: 20.80-21.53 t·hm-2), the system's net profit was significantly increased to 216 700-244 100 yuan·hm-2, which was 43.3-48.8 times that of MFC treatment. The net profit of SC+SR pattern was 12.6% higher than that of the FC+SR pattern. Compared with monocropped cotton, the double cropping patterns combined with straw and S. rugosoannulata residue returning significantly increased the contents of alkali-hydrolyzable nitrogen, available phosphorus, and available potassium in the 0-20 cm, 20-40 cm, and 40-60 cm soil layers. And the improvement effect of the SC+SR pattern was generally superior to that of FC+SR. [Conclusion] The cotton-S. rugosoannulata double cropping system is feasible in the Yellow River Basin, with the short-season cotton followed by S. rugosoannulata in succession planting (SC+SR) being the preferred choice. This pattern achieved the recycling of field straw resources and synergistic enhancement of economic benefits and soil fertility, serving as an effective pathway for promoting high-quality agricultural development in the cotton-growing regions of the Yellow River Basin.
[Objective] A disease that damages cotton fiber has been found in the Xinjiang cotton fields in recent years. The infected cotton fiber turned into mouse-gray and failed to fluff as the boll opens, losing all commercial value. The purpose of this study was to identify the pathogen causing lint rot in Xinjiang cotton fields, and to explore the relationship between mite and disease transmission. [Methods] A total of 161 diseased boll samples were collected from 25 cotton-growing units across northern and southern Xinjiang in 2021 and 2023. The strains were isolated and purified using the tissue isolation method. The pathogen was identified based on morphological characteristics, molecular biological analysis, and pathogenicity test. Different tissues and organs of cotton plants were artificially inoculated in the field to determine the infection sites of the pathogen. The correlation between cotton boll rot and mite was investigated by examining the occurrence frequency of the mite in diseased bolls in cotton field, and combining with the experiment of artificially inoculating healthy detached cotton bolls with mites carrying conidia. [Results] The cotton Nigrospora lint rot is widespread in Xinjiang cotton fields, and the damage is gradually worsening. A total of 146 Nigrospora strains were isolated from diseased samples collected from cotton fields in Xinjiang. The morphological characteristics of the strains were consistent with N. gorlenkoana. The DNA sequences of the internal transcribed spacer in eukaryotic ribose rDNA-ITS, translation elongation factor TEF1-α, and β-tubulin TUB2 in 27 representative strains exhibited high homology with N. gorlenkoana. Field and laboratory pathogenicity tests of 5 representative strains showed that the lint displayed extensive black-gray rot. Therefore, the pathogen causing cotton Nigrospora lint rot in Xinjiang was identified as N. gorlenkoana. The pathogen exclusively infected cotton fiber and did not affect seed, leaf, stem, bud, and flower of cotton. Siteroptes reniformis was closely associated with cotton Nigrospora lint rot. Adult mites or their physogastric females were found in all the diseased bolls, and they can carry the conidia of N. gorlenkoana into the bolls to spread the disease. [Conclusion] The cotton lint rot caused by N. gorlenkoana in Xinjiang in recent years is a disease specifically targeting cotton fiber, with S. reniformis as the primary transmission vector.
[Objective] This study aimed to investigate the role of sucrose in cotton resistance against Verticillium wilt and verify the function of GhSWEET55, providing a theoretical basis for revealing the molecular mechanism of cotton resistance to Verticillium wilt. [Methods] Cotton were inoculated with Verticillium dahliae using the root-wounding method. Sucrose content in cotton roots was determined by spectrophotometry. Differentially expressed genes were obtained by transcriptome sequencing. The enrichment of differentially expressed genes was studied by KEGG pathway analysis. Differentially expressed genes and SWEET family expression patterns were analyzed by transcriptome sequencing, and validated by quantitative real-time polymerase chain reaction (qRT-PCR). Bioinformatics analysis was performed to characterize the protein sequence features and phylogenetic relationships of GhSWEET55, and its expression pattern was analyzed by qRT-PCR. The function of GhSWEET55 was verified by virus-induced gene silencing (VIGS). [Results] Sucrose content in cotton roots increased significantly at 12 h and 48 h after V. dahliae infection, and decreased significantly at 96 h after V. dahliae infection. Some differentially expressed genes were enriched in sucrose-related energy metabolism pathways and defense response pathways. Most members of the SWEET family were differentially expressed, and GhSWEET55 from Clade III was significantly up-regulated. GhSWEET55 was predominantly expressed in cotton leaves, and the encoded protein was localized to the plasma membrane. Silencing of GhSWEET55 enhanced cotton resistance to Verticillium wilt. [Conclusion] Sucrose is involved in cotton resistance against Verticillium wilt. The SWEET gene family responds to V. dahliae infection. GhSWEET55 negatively regulates cotton resistance to V. dahliae.
[Objective] Forkhead box protein G1 (FOXG1), as a transcription factor, plays a crucial role in cell proliferation and differentiation. At present, the FOXG1 gene family has not been systematically studied in cotton. This research aimed to identify and analyze FOXG1 gene family in cotton. [Methods] FOXG1 gene family members were identified in cotton using bioinformatic approaches. Analyses were performed on the physicochemical properties, conserved motifs, and phylogenetic relationships of the corresponding proteins. The expression patterns of FOXG1 genes in Gossypium hirsutum and G. barbadense were investigated using transcriptome data. Preliminary functional exploration of the FOXG1 genes was conducted through association analysis between haplotypes of G. hirsutum FOXG1 genes and fiber quality traits, as well as via transgenic overexpression of GhFOXG1-4 gene in Arabidopsis thaliana. [Results] A total of 6, 5, 3, 3, 6, 6, 6, and 3 FOXG1 genes were identified in G. hirsutum, G. barbadense, G. raimondii, G. arboreum, G. tomentosum, G. mustelinum, G. darwinii, and G. herbaceum, respectively. These 38 FOXG1 proteins and 3 FOXG1 proteins of A. thaliana could be divided into 4 clades. GhFOXG1-1 was highly expressed in anther and ovule. GhFOXG1-2, GbFOXG1-1 and GbFOXG1-2 were highly expressed in anther, ovule and fiber. GhFOXG1-4 was highly expressed in ovule. GhFOXG1-4 and GhFOXG1-5 had 2 and 3 haplotypes, respectively. Significant differences in upper half mean length, breaking strength, and micronaire were observed among these haplotypes. The stem cell width of A. thaliana overexpressing GhFOXG1-4 gene was significantly larger than that of wild type. [Conclusion] A total of 38 FOXG1 genes were identified in 8 cotton species. The excellent haplotypes of some GhFOXG1 genes have the potential to synergistically improve fiber quality. GhFOXG1-4 positively regulates the stem cell width in A. thaliana, which lays a foundation for further study the function of FOXG1 family genes.
[Objective] This research aimed to investigate the effects of reclaimed water irrigation and different mulching methods on cotton growth, yield, and fiber quality. [Methods] A field experiment was conducted in Hutubi County, Changji Hui Autonomous Prefecture, Xinjiang in 2024. Six treatments were established: well water irrigation throughout the whole growth stage + straw mulching (T1); reclaimed water irrigation throughout the whole growth stage + straw mulching (T2); reclaimed water irrigation at critical water-demand stages (squaring stage and flowering and boll-setting stage) + straw mulching (T3); reclaimed water irrigation throughout the whole growth stage + plastic film mulching (T4); reclaimed water irrigation at critical water-demand stages + plastic film mulching (T5); and well water irrigation throughout the whole growth stage + plastic film mulching (CK). Cotton plant height, stem diameter, leaf area index (LAI), yield traits, irrigation water use efficiency (IWUE), and fiber quality were compared across different treatments. The entropy-weighted technique for order preference by similarity to ideal solution (TOPSIS) method was used for comprehensive evaluation to select the optimal treatment. Meanwhile, the heavy metal contents in the soil and different cotton organs were determined and analyzed. [Results] During the flowering and boll-setting stage, and boll-opening stage, reclaimed water irrigation significantly increased plant height, stem diameter, and LAI compared with well water irrigation. The plant height, stem diameter, and LAI under straw mulching were greater than those under plastic film mulching; the T2 treatment exhibited the maximum plant height, stem diameter, and LAI. T2 also achieved the highest seed cotton yield, lint yield, and IWUE, and upper half mean length, breaking tenacity, breaking elongation, and micronaire of fiber of T2 were superior to those of other treatments. Comprehensive evaluation using entropy-weighted TOPSIS showed that the T2 treatment performed best. Compared with well water irrigation, reclaimed water irrigation significantly increased the contents of chromium (Cr) and lead (Pb) in the 0-60 cm soil layer and Cr content in cotton roots, stems, and leaves, while significantly reducing the arsenic (As) content in the 0-60 cm soil layer and cotton roots. However, the contents of mercury (Hg), cadmium (Cd), Cr, Pb, and As in soil and cotton plants under different treatments were all below the risk screening values. [Conclusion] Under the conditions of this experiment, the combination of reclaimed water irrigation throughout the whole growth stage and straw mulching showed the best comprehensive performance.
[Objective] This study aims to address the issues of impurity contamination in machine-picked seed cotton in Xinjiang and the low efficiency of manual sorting, we propose a highly efficient and precise method for detecting impurities in seed cotton to enhance cotton quality. [Methods] An improved CID-YOLO model is introduced based on YOLO v11. Firstly, a normalization-based attention mechanism module is introduced to enable the network to balance target channel features and pixel features while reducing parameter count and computational complexity, thereby improving detection accuracy. Secondly, according to the characteristics that the detected target is easy to appear at the edge, the lightweight adaptive convolution module is used to replace some convolution modules in the backbone network and neck network, which can better preserve the edge and structure information of the sampling phase, and effectively reduce the amount of parameters. Finally, an efficient layer aggregation network is used to replace the improved pyramid pooling module in the backbone network to enhance the ability of feature multi-scale extraction and information aggregation, so as to improve the perception performance of targets of different scale targets in complex background. [Results] Experimental results demonstrate that the CID-YOLO model achieves outstanding performance in seed cotton impurity detection, with a detection accuracy of 92.1%, recall of 89.5%, F1 score of 90.8%, and mean average precision of 92.8%. Its overall recognition effectiveness significantly outperforms existing YOLO series models. [Conclusion] The proposed CID-YOLO method enables rapid and precise identification of drip irrigation tapes, colored impurities, cotton stalks, and plastic mulch in machine-picked seed cotton. It provides effective technical support for real-time seed cotton impurity detection and holds promising application prospects.
[Objective] Construct a yeast two-hybrid (Y2H) library of Gossypium barbadense, and screen for interacting proteins of GbbHLH130 using Y2H assays. [Methods] This study constructed a Y2H library of G. barbadense using the Gateway technique, and employed the Y2H system to screen for candidate proteins interacting with GbbHLH130. [Results] This study successfully constructed a G. barbadense Y2H library, with a second library capacity of 1.36 × 107 CFU, and insert fragment length >1 000 bp, and a recombination rate of 100%. Using Y2H technology, 298 initial positive clones were screened, and the interaction between GbRAV1, GbHSFA1b, and GbbHLH130 was verified through Y2H assays. [Conclusion] This study successfully constructed a Y2H library of G. barbadense and preliminarily screened candidate interacting proteins for GbbHLH130. GbRAV1 and GbHSFA1b were verified to interact with GbbHLH130 through Y2H assays, suggesting that they may play a role in the biological process of response to drought stress mediated by GbbHLH130. However, their interaction mechanisms and specific roles in drought response need further research.
