Project description:For environmental safety, the high concentration of heavy metals in the soil should be removed. Cadmium (Cd), one of the heavy metals polluting the soil while its concentration exceeds 3.4 mg/kg in soil. Potential use of cotton for remediating heavy Cd-polluted soils is available while its molecular mechanisms of Cd tolerance remains unclear in cotton. In this study, transcriptome analysis was used to identify the Cd tolerance genes and their potential mechanism in cotton. Finally 4,627 differentially expressed genes (DEGs) in the root, 3,022 DEGs in the stem and 3,854 DEGs in leaves were identified through RNA-Seq analysis, respectively. These genes contained heavy metal transporter genes (ABC, CDF, HMA, etc.), annexin genes, heat shock genes (HSP) amongst others. Gene ontology (GO) analysis showed that the DEGs were mainly involved in the oxidation-reduction process and metal ion binding. The DEGs mainly enriched in two pathways, the influenza A and the pyruvate pathway. GhHMAD5 protein, containing a heavy-metal domain, was identified in the pathway to transport or to detoxify the heavy ion. GhHMAD5-overexpressed plants of Arabidopsis thaliana showed the longer roots compared with the control. Meanwhile, GhHMAD5-silenced cotton plants showed more sensitive to Cd stress compared with the control. The results indicated that GhHMAD5 gene is remarkably involved in Cd tolerance, which gives us a preliminary understanding of Cd tolerance mechanisms in upland cotton. Overall, this study provides valuable information for the use of cotton to remediate the soil polluted with heavy metals.
Project description:This study was designed to identify the sRNAs in Aphis gossypii (cotton-melon aphid) during Vat-mediated resistance in teraction with melon
Project description:In cotton, after the Bt introduction, lepidopteron pest attack been reduced to a greater extent, however, the sucking pests became major problem. Among the sucking pests, the leafhopper Amrasca biguttula biguttula (Ishida), considered to be a severe pest. Here, we reported the label-free quantitative proteomics to identify putative differentially expressed proteins contributing to leafhopper resistance. The results obtained from this work not only aimed to provide a new clue that will facilitate better understanding of molecular interaction between cotton plant and leafhopper, but also explored the key genes for the development of functional markers in cotton towards leafhopper resistance.
Project description:Verticillium wilt which is caused by Verticillium dahliae causes massive annual losses of cotton yield. Control by conventional mechanisms is not possible due to wide host range and longevity of dormant fungi in the soil in case of absence of a suitable host. Plants have developed various mechanisms to boost their immunity against various diseases, and one of which is through the induction of various genes. In this research work, carried out of RNA sequencing and identified the members of the ABC genes are critical in enhancing resistance to V. dahliae infection. A total of 166 ABC genes were identified in Gossypium raimondii with varying physiochemical properties. A novel ABC gene, Gorai.007G244600 was found to be highly upregulated, its homolog in the tetraploid cotton Gh_D11G3432, was then silenced through virus induced gene silencing (VIGS) in tetraploid cotton, the mutant cotton seedlings that have the ability to tolerate V. dahliae infection were significantly reduced. Evaluation of oxidant, hydrogen peroxide (H2O2) and malondialdehyde (MDA) were found to have increased levels in the leaves of the mutant compared to the wild types. In addition, antioxidant enzymes, peroxidase (POD), catalase (CAT) and superoxide dismutase (SOD) concentration levels were significantly reduced in the mutant cotton compared to the wild types. Moreover, expression levels of the biotic stress genes, cotton polyamine oxidase (GhPAO), cotton ribosomal protein L18(GhRPL18) and cotton polygalacturonase-inhibiting protein-1 (GhPGIP1) were all downregulated in the mutant but highly upregulated in the wild cotton tissues. The outcome of this research has shown that ABC genes could be playing an important role in enhancing immunity of cotton to V. dahliae infection and can be explored in developing more resilient cotton genotypes with improved resistance to V. dahliae infection.
Project description:To examine expression of miRNAs in cotton fiber development, we employed miRNA microarrays and compared miRNA accumulation level in cotton fibers, cotton leaves and mutant fibers.
Project description:Cotton is the main source of natural fiber in the textile industry, making it one of the most economically important fiber crops in the world. Verticillium wilt, caused by the pathogenic fungus Verticillium dahlia, is one of the most damaging biotic factors limiting cotton production. Mechanistic details of cotton defense responses to verticillium wilt remain unclear. In this study, GFP-labeled strain of V. dahlia was used to track colonization in cotton roots, and clear conidial germination could be observed at 48 hours post-inoculation (hpi), marking this as a crucial time point during infection. Transcriptome analysis identified 1,523 and 8,270 differentially expressed genes (DEGs) at 24 hpi and 48 hpi, respectively. Metabolomic screening found 78 differentially accumulated metabolites (DAMs) at 48 hpi. Conjoint analysis indicated that the phenylpropanoid biosynthesis pathway was activated in cotton infected with V. dahliae. The five metabolites in the phenylpropanoid biosynthesis pathway, including caffeic acid, coniferyl alcohol, coniferin, scopoletin and scopolin, could significantly inhibit V. dahlia growth in vitro, implicating their roles in cotton resistance to Verticillium wilt. The findings expand our understanding of molecular mechanisms underlying the pathogen defense response against V. dahlia infection in upland cotton, which may lead to future insights into controlling Verticillium wilt disease.
Project description:Sea Island cotton (Gossypium barbadense) is the source of the world’s finest fiber-quality cotton, yet relatively little is understood about the genetic variation among diverse germplasm, the genes underlying important traits, and the effects of pedigree selection. Here, we resequenced 336 G. barbadense accessions and identified 16 million SNPs. Phylogenetic and population structure analyses revealed two major gene pools and a third admixed subgroup derived from geographical dissemination and interbreeding. We conducted a genome-wide association study (GWAS) of 15 traits including fiber quality, yield, disease resistance, maturity, and plant architecture. The highest number of associated loci was for fiber quality, followed by disease resistance and yield. Using gene expression analyses and VIGS transgenic experiments we confirmed the role of five candidate genes regulating four key traits, i.e., disease resistance, fiber length, fiber strength, and lint percentage. Geographical and temporal considerations demonstrate selection for the superior fiber quality (fiber length and fiber strength), and high lint-percentage in improving G. barbadense in China. Pedigree selection breeding wholly increased Fusarium wilt disease resistance, and separately improved fiber-quality and yield. Our work provides a foundation for understanding genomic variation in and selective breeding of Sea Island cotton.
Project description:The interaction between soybean and its destructive insect (cotton worm) is complicated. In this paper, the timecourse of induced responses to cotton worm were characterized in two soybean lines, suggesting complex results with different timepoints of peak induced resistance in resistant (WX) and susceptible (NN) soybean lines. To get a better understanding of induced resistant mechanisms of soybean against herbivory, two sets of transcriptome profiles of WX and NN at their peak induced resistant timepoints were compared by microarrays