共检索到256条,权限内显示50条;
[学术文献 ] CRISPR/Cas9-mediated GhFT-targeted mutagenesis prolongs indeterminate growth and alters plant architecture in cotton 进入全文
PLANT SCIENCE
The shift from vegetative to reproductive growth is an important developmental transition that affects flowering and maturation, architecture, and ecological adaptability in plants. The florigen-antiflorigen system universally controls flowering and plant architecture, and changes to the ratio of these components alter this transition and disrupt growth. The genes FT (FLOWERING LOCUS T), encoding the florigen protein FT, and CETS [CENTRORADIALIS (CEN)/TERMINAL FLOWER1 (TFL1)/SELF-PRUNING (SP)], encoding antiflorigen proteins, have opposing roles. Upland cotton (Gossypium hirsutum) is one of the world's most widely cultivated cotton varieties, and its complex allotetraploid genome contains only one homoeologous pair of FT genes (GhFT-A and GhFT-D). The functionally conserved gene GhFT promotes flowering and plays a role in plant architecture, although the molecular regulation of flowering and plant architecture in cotton remains unclear. In this study, CRISPR/Cas9 technology was used to induce mutations in the first and second exons of GhFT, respectively. G. hirsutum cv. YZ-1 was transformed with a CRISPR/Cas9-GhFT vector using Agrobacterium tumefaciens, and a diverse set of mutations was identified at the editing site. Compared with the wild type, mutant plants could not transition between vegetative and reproductive growth, and significant alterations to plant architecture were observed. Quantitative RT-PCR revealed downregulation of the homologous floral meristem identity genes APETALA1 (GhAP1) and OVEREXPRESSION OF CONSTANS 1 (GhSOC1) and upregulation of the TFL1 homologs GhTFL1-1 and GhTFL1-2. These results suggested that GhFT played a significant role in flowering time and plant architecture and that the ratio of florigen-antiflorigen components was critical to producing improved cotton varieties. This study provided a basis for future investigations of molecular breeding in cotton and guidance for the agricultural production of this crop.
[学术文献 ] Optimized nitrogen allocation in cotton-soil system improves cotton production and nitrogen utilization efficiency under wheat-cotton straw return in East China 进入全文
INDUSTRIAL CROPS AND PRODUCTS
In wheat-cotton rotation system, the strained photo-thermal resources after harvesting wheat pose challenges to cotton growth in terms of the utilization of temperature, light and fertilizer, especially in nitrogen. The purpose of the study was to explore suitable agricultural management practices for sustainable cotton production and soil productivity under wheat-cotton system. Two straw managements (straw return and straw removal) and four nitrogen rates (0, 75, 150 and 300 kg N ha-1, defined as N0, N75, N150 and N300, respectively) were adopted as the variables. The results showed that under straw return with N150, where cotton yield and fiber quality reached to the maximum, the highest apparent nitrogen recovery efficiency of 75.9 %-92.7 % and the maximum ratios of cotton boll number and cotton yield over the efficient photo-thermal phase to them at the harvesting stage were obtained. 15N-labeling indicated that optimal nitrogen application could improve fertilizer nitrogen uptake in cotton before flowering and straw return increased cotton nitrogen uptake from soil. Furthermore, straw return increased nitrogen fertilizer retention at the 0-20 cm soil depth. Under straw return with N150, more nitrogen fertilizer was stored as organic nitrogen (40.9 %) and microbial biomass nitrogen (11.8 %). Therefore, increasing nitrogen fertilizer retention in the topsoil might attribute to improving microbial nitrogen fixation. In addition, straw return improved fertilizer nitrogen that cotton boll allocated to fiber and that seedcotton allocated to seed kernel and fiber at N150. According to these findings, we are led to conclude that under straw return, optimal nitrogen application of N150 improved cotton boll development over the efficient photo-thermal phase and nitrogen allocation in cotton-soil system, increasing nitrogen utilization efficiency and cotton production.
[学术文献 ] Low Phosphorus Stress Decreases Cotton Fiber Strength by Inhibiting Carbohydrate Metabolism 进入全文
JOURNAL OF PLANT GROWTH REGULATION
Insufficient soil-available phosphorus (AP) inhibits photosynthesis and sucrose metabolism in the subtending leaves to cotton bolls, significantly reducing lint yield and fiber length. However, the mechanism by which P deficiency affects cotton fiber strength remains unclear. This study explored the influence of P deficiency on the fiber strength of two cotton varieties, CCRI-79 (low-P tolerant) and SCRC-28 (low-P sensitive). A two-year pool-culture experiment was conducted under three soil AP levels: P0 (3 +/- 0.5), P1 (6 +/- 0.5), and P2 (control, 15 +/- 0.5 mg kg-1). Soil AP deficiency (P1 and P0) decreased the activities of enzymes involved in fiber thickening, including soluble acid invertase (SAI), sucrose synthase (SuSy), sucrose phosphate synthase (SPS), and beta-1,3-glucanase. These reductions led to a 4.0%-16.9% decrease in cellulose content, which was a key substance for fiber strength formation. In addition, the reduced enzymatic activity decreased the maximum velocity of fiber thickening increment (VSmax), ultimately resulting in a 1.0-3.9 cN tex-1 decrease in fiber strength. The beta-1,3-glucan and cellulose levels, as well as SAI and beta-1,3-glucanase activities, showed more pronounced responsiveness to soil AP deficiency in SCRC-28 than in CCRI-79. This indicates that SCRC-28 fibers were more adversely affected under low soil AP levels. Cellulose, SAI, and beta-1,3-glucanase were the key factors affecting fiber strength under low soil AP conditions. This study contributes to a deeper understanding of how soil AP deficiency influences fiber carbohydrate metabolism and fiber strength, offering a scientific basis for breeding low-P tolerant cotton cultivars.
[学术文献 ] Patterns of phenotypic variation in Gossypium turneri: a wild cotton with a restricted distribution in Sonora, Mexico 进入全文
GENETIC RESOURCES AND CROP EVOLUTION
Crop wild relatives (CWR) represent important genetic resources for crop improvement. Gossypium turneri, a wild cotton species with a restricted distribution in the Sonoran Desert of northwestern Mexico, has been identified as a potential breeding resource for cotton improvement. While several agronomically important traits have been previously identified through limited observations from only one location within its range, phenotypic variation in this xerophytic species has not been thoroughly studied. This study aimed to describe the pattern of phenotypic variation in floral and leaf traits along the three known populations of G. turneri and identify traits of agronomic interest. Leaves and flowers through its distribution range were collected and quantitative and qualitative attributes were analyzed. Phenotypic variation in flowers and leaves was predominantly found among individuals within populations, with a smaller proportion occurring between populations, likely due to the species' restricted distribution. Interpopulation variation in leaf traits was probably influenced by differences in local rainfall, whereas flower traits exhibited minimal interpopulation variation, likely due to similarities in pollinator composition. Some traits of interest for cotton improvement were identified, such as polymorphic bracts and production of anthers without pollen among flowers. This desert-adapted wild cotton offers valuable traits with potential for adaptation of cultivated cotton to water- and heat-stressed environments.
[学术文献 ] GhLPF1 Associated Network Is Involved with Cotton Lint Percentage Regulation Revealed by the Integrative Analysis of Spatial Transcriptome 进入全文
ADVANCED SCIENCE
Cotton fibers, derived from the epidermis of the ovule, provide a sustainable natural fiber source for the textile industry. Traits related to fiber yield are predominantly determined by molecular regulations in the epidermis of the outer integument (OI) region of the cotton ovule. Here, we identify an R2R3 MYB transcription factor coding gene GhLPF1 within the QTL-LP-ChrA06 locus for lint percentage (LP, percentage of lint to seed cotton) through constructing the 1-Day Post Anthesis Cotton Ovule Spatial Transcriptome Atlas. GhLPF1 is subjected as a downstream target of miR828 during fiber development. The direct downstream genes (DDGs) of GhLPF1 are biased to increased expression in GhLPF1-CR, and are preferentially expressed in OI, so that GhLPF1 is primarily a transcriptional repressor to its DDGs. Population-wide transcriptome analysis confirms that expression variation of GhLPF1-DDGs is significantly biased to negative correlation with LP, among which a type I homeobox protein-coding gene GhHB6 is further validated to be the directly downstream gene of GhLPF1. Given these data, it is demonstrated that GhLPF1 mediates a regulation network in LP as a transcriptional repressor, which makes it a valuable functional marker for fiber-trait improvement application from QTL-LP-ChrA06.
[学术文献 ] Insights into the Role of GhTAT2 Genes in Tyrosine Metabolism and Drought Stress Tolerance in Cotton 进入全文
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
Gossypium hirsutum is a key fiber crop that is sensitive to environmental factors, particularly drought stress, which can reduce boll size, increase flower shedding, and impair photosynthesis. The aminotransferase (AT) gene is essential for abiotic stress tolerance. A total of 3 Gossypium species were analyzed via genome-wide analysis, and the results unveiled 103 genes in G. hirsutum, 47 in G. arboreum, and 53 in G. raimondii. Phylogenetic analysis, gene structure examination, motif analysis, subcellular localization prediction, and promoter analysis revealed that the GhAT genes can be classified into five main categories and play key roles in abiotic stress tolerance. Using RNA-seq expression and KEGG enrichment analysis of GhTAT2, a coexpression network was established, followed by RT-qPCR analysis to identify hub genes. The RT-qPCR results revealed that the genes Gh_A13G1261, Gh_D13G1562, Gh_D10G1155, Gh_A10G1320, and Gh_D06G1003 were significantly upregulated in the leaf and root samples following drought stress treatment, with Gh_A13G1261 identified as the hub gene. The GhTAT2 genes were considerably enriched for tyrosine, cysteine, methionine, and phenylalanine metabolism and isoquinoline alkaloid, tyrosine, tryptophan, tropane, piperidine, and pyridine alkaloid biosynthesis. Under drought stress, KEGG enrichment analysis manifested significant upregulation of amino acids such as L-DOPA, L-alanine, L-serine, L-homoserine, L-methionine, and L-cysteine, whereas metabolites such as maleic acid, p-coumaric acid, quinic acid, vanillin, and hyoscyamine were significantly downregulated. Silencing the GhTAT2 gene significantly affected the shoot and root fresh weights of the plants compared with those of the wild-type plants under drought conditions. RT-qPCR analysis revealed that GhTAT2 expression in VIGS-treated seedlings was lower than that in both wild-type and positive control plants, indicating that silencing GhTAT2 increases sensitivity to drought stress. In summary, this thorough analysis of the gene family lays the groundwork for a detailed study of the GhTAT2 gene members, with a specific focus on their roles and contributions to drought stress tolerance.
