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KEY MESSAGE: Two genomic regions associated with FFBN and HFFBN and a potential regulatory gene (GhE6) of HFFBN were identified through the integration of RTM-GWAS and metaQTL analyses. Abstract The first fruit branch node (FFBN) and the height of the first fruit branch node (HFFBN) are two important traits that are related to plant architecture and early maturation in upland cotton. Several studies have been conducted to elucidate the genetic basis of these traits in cotton using biparental and natural populations. In this study, by using 9,244 SNP linkage disequilibrium block (SNPLDB) loci from 315 upland cotton accessions, we carried out restricted two-stage multilocus and multiallele genome-wide association studies (RTM-GWASs) and identified promising haplotypes/alleles of the four stable and true major SNPLDB loci that were significantly associated with FFBN and HFFBN. Additionally, a meta-quantitative trait locus (MQTL) analysis was conducted on 274 original QTLs that were reported in 27 studies, and 40 MQTLs associated with FFBN and HFFBN were identified. Through the integration of the RTM-GWAS and metaQTL analyses, two stable and true major SNPLDBs (LDB_5_15144433 and LDB_16_37952328) that were distributed in the two MQTLs were identified. Ultimately, 142 genes in the two genomic regions were annotated, and three candidate genes associated with FFBN and HFFBN were identified in the genomic region (A05:14.64-15.64 Mb) via RNA-Seq and qRTâPCR. The results of virus-induced gene silencing (VIGS) experiments indicated that GhE6 was a key gene related to HFFBN and that GhDRM1 and GhGES were important genes associated with early flowering in upland cotton. These findings will aid in the future identification of molecular markers and genetic resources for developing elite early-maturing cultivars with ideal plant characteristics.
Assuntos
Mapeamento Cromossômico , Gossypium , Desequilíbrio de Ligação , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , Gossypium/genética , Gossypium/crescimento & desenvolvimento , Fenótipo , Genes de Plantas , Haplótipos , Estudos de Associação Genética , Alelos , Estudo de Associação Genômica Ampla , Frutas/genética , Frutas/crescimento & desenvolvimentoRESUMO
The VIM (belonged to E3 ubiquitin ligase) gene family is crucial for plant growth, development, and stress responses, yet their role in salt stress remains unclear. We analyzed phylogenetic relationships, chromosomal localization, conserved motifs, gene structure, cis-acting elements, and gene expression patterns of the VIM gene family in four cotton varieties. Our findings reveal 29, 29, 17, and 14 members in Gossypium hirsutum (G.hirsutum), Gossypium barbadense (G.barbadense), Gossypium arboreum (G.arboreum), and Gossypium raimondii (G. raimondii), respectively, indicating the maturity and evolution of this gene family. motifs among GhVIMs genes were observed, along with the presence of stress-responsive, hormone-responsive, and growth-related elements in their promoter regions. Gene expression analysis showed varying patterns and tissue specificity of GhVIMs genes under abiotic stress. Silencing GhVIM28 via virus-induced gene silencing revealed its role as a salt-tolerant negative regulator. This work reveals a mechanism by which the VIM gene family in response to salt stress in cotton, identifying a potential negative regulator, GhVIM28, which could be targeted for enhancing salt tolerance in cotton. The objective of this study was to explore the evolutionary relationship of the VIM gene family and its potential function in salt stress tolerance, and provide important genetic resources for salt tolerance breeding of cotton.
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Regulação da Expressão Gênica de Plantas , Gossypium , Família Multigênica , Filogenia , Proteínas de Plantas , Estresse Salino , Gossypium/genética , Gossypium/fisiologia , Estresse Salino/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Genes de Plantas , Tolerância ao Sal/genéticaRESUMO
BACKGROUND: DNA methylation is an important epigenetic mode of genomic DNA modification and plays a vital role in maintaining epigenetic content and regulating gene expression. Cytosine-5 DNA methyltransferase (C5-MTase) are the key enzymes in the process of DNA methylation. However, there is no systematic analysis of the C5-MTase in cotton so far, and the function of DNMT2 genes has not been studied. METHODS: In this study, the whole genome of cotton C5-MTase coding genes was identified and analyzed using a bioinformatics method based on information from the cotton genome, and the function of GhDMT6 was further validated by VIGS experiments and subcellular localization analysis. RESULTS: 33 C5-MTases were identified from three cotton genomes, and were divided into four subfamilies by systematic evolutionary analysis. After the protein domain alignment of C5-MTases in cotton, 6 highly conserved motifs were found in the C-terminus of 33 proteins involved in methylation modification, which indicated that C5-MTases had a basic catalytic methylation function. These proteins were divided into four classes based on the N-terminal difference, of which DNMT2 lacks the N-terminal regulatory domain. The expression of C5-MTases in different parts of cotton was different under different stress treatments, which indicated the functional diversity of cotton C5-MTase gene family. Among the C5-MTases, the GhDMT6 had a obvious up-regulated expression. After silencing GhDMT6 with VIGS, the phenotype of cotton seedlings under different stress treatments showed a significant difference. Compared with cotton seedlings that did not silence GhDMT6, cotton seedlings silencing GhDMT6 showed significant stress resistance. CONCLUSION: The results show that C5-MTases plays an important role in cotton stress response, which is beneficial to further explore the function of DNMT2 subfamily genes.
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Secas , Gossypium , Gossypium/genética , Gossypium/enzimologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Metilação de DNA , Regulação da Expressão Gênica de Plantas , Tolerância ao Sal/genética , Família Multigênica , DNA (Citosina-5-)-Metiltransferases/genética , DNA (Citosina-5-)-Metiltransferases/metabolismo , Filogenia , Genoma de Planta , Genes de PlantasRESUMO
Plants experience diverse abiotic stresses, encompassing low or high temperature, drought, water logging and salinity. The challenge of maintaining worldwide crop cultivation and food sustenance becomes particularly serious due to drought and salinity stress. Sustainable agriculture has significant promise with the use of nano-biotechnology. Nanoparticles (NPs) have evolved into remarkable assets to improve agricultural productivity under the robust climate alteration and increasing drought and salinity stress severity. Drought and salinity stress adversely impact plant development, and physiological and metabolic pathways, leading to disturbances in cell membranes, antioxidant activities, photosynthetic system, and nutrient uptake. NPs protect the membrane and photosynthetic apparatus, enhance photosynthetic efficiency, optimize hormone and phenolic levels, boost nutrient intake and antioxidant activities, and regulate gene expression, thereby strengthening plant's resilience to drought and salinity stress. In this paper, we explored the classification of NPs and their biological effects, nanoparticle absorption, plant toxicity, the relationship between NPs and genetic engineering, their molecular pathways, impact of NPs in salinity and drought stress tolerance because the effects of NPs vary with size, shape, structure, and concentration. We emphasized several areas of research that need to be addressed in future investigations. This comprehensive review will be a valuable resource for upcoming researchers who wish to embrace nanotechnology as an environmentally friendly approach for enhancing drought and salinity tolerance.
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The effects of 20%-40% fertilizer reduction and different organic fertilizers on soil microbial biomass, enzyme activity and cotton yield were examined for three consecutive years in Hexi area of Gansu, Northwest China. The results showed that compared with single chemical fertilizer application, the abundance of soil bacteria and actinomycetes were significantly increased while that of fungi were decreased with chemical fertilizer reduction combined with organic fertilizer. The abundance of soil bacteria was maximum under the treatment of chemical fertilizer reduction combined with common organic fertilizer and bio-organic fertilizer (COBF2), which was 84.6%, 57.1% and 43.5% higher than that under single application of chemical fertilizer (CF) in the bud stage, boll stage and boll open stage, while the abundance of actinomycetes was maximum under the chemical fertilizer reduction combined with common bio-organic fertilizer (CBF2), which was 28.2%, 32.7% and 32.2% higher than CF. The abundance of fungi was the lowest in the CBF2 treatment, which was 35.8%, 29.3%and 13.4% lower than CF treatment in three periods. The ratios of bacteria to fungi, actinomycetes to fungi and the activity of soil urease, catalase, sucrase and alkaline phosphatase were increased by the chemical fertilizer reduction combined with organic fertilizer. COBF2 was the most effective way to improve enzyme activity. Fertilizer reduction combined with the application of organic fertilizer increased boll number per individual of cotton plant, promoted cotton growth and dry matter accumulation in the ground to a certain extent. The cotton yield under COBF2 treatment was the highest, which showed an significant increase of 14.2% and 10.9% respectively in seed and lint cotton yield than CF. Our results showed that COBF2, with 60% reduction of chemical fertilizer combined with 1800 kg·hm-2 ordinary organic fertilizer and 600 kg·hm-2 biological organic fertilizer, had the best fertilization effect.
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Fertilizantes , Solo , Agricultura , Biomassa , China , Microbiologia do SoloRESUMO
Upland cotton is the most important natural-fiber crop. The genomic variation of diverse germplasms and alleles underpinning fiber quality and yield should be extensively explored. Here, we resequenced a core collection comprising 419 accessions with 6.55-fold coverage depth and identified approximately 3.66 million SNPs for evaluating the genomic variation. We performed phenotyping across 12 environments and conducted genome-wide association study of 13 fiber-related traits. 7,383 unique SNPs were significantly associated with these traits and were located within or near 4,820 genes; more associated loci were detected for fiber quality than fiber yield, and more fiber genes were detected in the D than the A subgenome. Several previously undescribed causal genes for days to flowering, fiber length, and fiber strength were identified. Phenotypic selection for these traits increased the frequency of elite alleles during domestication and breeding. These results provide targets for molecular selection and genetic manipulation in cotton improvement.