Comparative plant biochemistry and soil biology of wild and cultivated cotton species

Purpose No attempts were made to analyze the diversity in soil and plant biology of wild cotton species (WCS) and cultivated cotton species (CCS), so far. Our study aimed to understand the differences in soil biological, plant biochemistry, and defense enzyme activities among the ten WCS and four CCS. Methods We studied the differences in soil biology, plant biochemistry, and defense enzyme activities among the ten WCS (Gossypium anomalum, G. aridum, G. australe, G. barbosanum, G. capitis-virides, G. davidsonii, G. raimondii, G. somalense, G. stocksii, G. thurberi) and four CCS (G. arboreum, G. herbaceum, G. hirsutum, and G. barbadense). Results CCS had 11%, 2%, and 10% higher soil respiration rate, microbial biomass carbon, and microbial metabolic quotient, respectively, compared to WCS. While, WCS had 45%, 15%, and 5% higher glomalin, soil polysaccharide, proteins, respectively, compared to CCS. WCS had 45%, 13%, 8%, and 13% higher acid and alkaline phosphatase, β-glucosidase, and soil dehydrogenase activities, respectively, compared to CCS. WCS had higher carbohydrates in the shoot (40%) and root (27%), while, CCS recorded higher proteins in the shoot (13%) and root (13%). WCS had significantly higher polyphenol oxidase (4% and 15%), peroxidase (30% and 31%), and catalase (36% and 31%) activities in shoots and root tissues, respectively, compared with CCS, while, WCS had higher phenol concentrations (4%) than CCS. Conclusion Our study suggests that the difference in soil biological, plant biochemistry, and defense enzyme activities among the WCS and CCS can be attributed to the inherent genetic makeup, which influences consequent plant and soil attributes.

Stories from the Greenhouse—A Brief on Cotton Seed Germination

Seed germination is the basis for the proliferation of sexual-reproducing plants, efficient crop production, and a successful crop improvement research program. Cotton (Gossypium spp.), the subject of this review, can be often sensitive to germination conditions. The hardness of the cotton seed coat, storage, extreme temperatures, and dormancy are some of the factors that can influence cotton seed germination. Research programs conducting studies on exotic and wild cotton species are especially affected by those hurdles. Here, we briefly review the challenges of cotton seed germination and some of the approaches our cotton breeding program explored throughout the years.

GhGLK1 a Key Candidate Gene From GARP Family Enhances Cold and Drought Stress Tolerance in Cotton

Drought and low-temperature stresses are the most prominent abiotic stresses affecting cotton. Wild cotton being exposed to harsh environments has more potential to cope with both biotic and abiotic stresses. Exploiting wild cotton material to induce resistant germplasm would be of greater interest. The candidate gene was identified in the BC2F2 population among Gossypium tomentosum and Gossypium hirsutum as wild male donor parent noted for its drought tolerance and the recurrent parent and a high yielding but drought susceptible species by genotyping by sequencing (GBS) mapping. Golden2-like (GLK) gene, which belongs to the GARP family, is a kind of plant-specific transcription factor (TF) that was silenced by virus-induced gene silencing (VIGS). Silencing of GhGLK1 in cotton results in more damage to plants under drought and cold stress as compared with wild type (WT). The overexpression of GhGLK1 in Arabidopsis thaliana showed that the overexpressing plants showed more adaptability than the WT after drought and cold treatments. The results of trypan blue and 3,3′-diaminobenzidine (DAB) staining showed that after drought and cold treatment, the leaf damage in GhGLK1 overexpressed plants was less as compared with the WT, and the ion permeability was also lower. This study suggested that the GhGLK1 gene may be involved in the regulation of drought and cold stress response in cotton. Our current research findings add significantly to the existing knowledge of cold and drought stress tolerance in cotton.

Genome survey sequencing of wild cotton (Gossypium robinsonii) reveals insights into proteomic responses of pollen to extreme heat

ABSTRACTHeat stress specifically affects fertility by impairing pollen viability but cotton wild relatives successfully reproduce in hot savannas where they evolved. An Australian heat-tolerant cotton (Gossypium robinsonii) was exposed to heat events during pollen development, then mature pollen was subjected to deep proteomic analysis using 57,023 predicted genes from a genomic database we assembled for the same species. Three stages of pollen development, including tetrads, uninucleate and binucleate microspores were exposed to 36°C or 40°C for 5 d and the resulting mature pollen was collected at anthesis (p-TE, p-UN and p-BN, respectively). Using SWATH-MS proteomic analysis, 2,704 proteins were identified and quantified across all pollen samples analyzed. Proteins predominantly decreased in abundance at all stages in response to heat, particularly after exposure of tetrads to 40°C. Functional enrichment analyses demonstrated that extreme heat increased the abundance of proteins that contributed to increased mRNA splicing via spliceosome, initiation of cytoplasmic translation and protein refolding in p-TE40. However, other functional categories that contributed to intercellular transport were inhibited in p-TE40, linked potentially to Rab proteins. We ascribe the resilience of reproductive processes in G. robinsonii at temperatures up to 40°C, relative to commercial cotton, to a targeted reduction in protein transport.

Unveiling the Gut Microbiota and Resistome of Wild Cotton Mice, Peromyscus gossypinus , from Heavy Metal- and Radionuclide-Contaminated Sites in the Southeastern United States

Antimicrobial resistance is a serious global public health concern because of its prevalence and ubiquitous distribution. The rapid dissemination of antibiotic resistance genes is thought to be the result of the massive overuse of antibiotics in agriculture and therapeutics.

Transcriptome Analysis Reveals Drought Stress response Mediated by Biological Processes and Key Pathways in Gossypium darwinii

Background: The allotetraploid wild cotton species, Gossypium darwinii, possess important traits of stress tolerance and good genetic stability that can be used for cotton improvement. In this study, we analyzed the RNA-seq transcriptomes from leaves of G. darwinii seedlings with and without drought stress. Results: A total of 86.7 million valid reads with an average length of 95.79 bp were generated from the two samples and 58,960 transcripts with a length of more than 500 bp were assembled. We searched the known proteins on the strength of sequence similarity; these transcripts were annotated with COG, KEGG, and GO functional categories. According to gene expression abundance RPKM value, we carried out RT-qPCR analysis to determine the expression pattern of the obtained transcription factors. A total of 58,961 genes was differentially expressed (DEG), with 32,693 and 25,919 genes found to be upregulated and downregulated, respectively. Through gene ontology and KEGG pathways, the upregulated genes were found to associate with all the GO terms, molecular functions (MF), biological process (BP) and cellular components (CC), which are highly linked to enhancing drought stress tolerance. The results obtained provide valuable information and a large number of transcripts, which can be exploited by cotton breeders in developing a more drought stress tolerant cotton germplasm.

The Gossypium stocksii genome as a novel resource for cotton improvement

Cotton is an important textile crop whose gains in production over the last century have been challenged by various diseases. Because many modern cultivars are susceptible to several pests and pathogens, breeding efforts have included attempts to introgress wild, naturally resistant germplasm into elite lines. Gossypium stocksii is a wild cotton species native to Africa, which is part of a clade of vastly understudied species. Most of what is known about this species comes from pest resistance surveys and/or breeding efforts, which suggests that G. stocksii could be a valuable reservoir of natural pest resistance. Here we present a high-quality de novo genome sequence for G. stocksii. We compare the G. stocksii genome with resequencing data from a closely related, understudied species (G. somalense) to generate insight into the relatedness of these cotton species. Finally, we discuss the utility of the G. stocksii genome for understanding pest resistance in cotton, particularly resistance to cotton leaf curl virus.

The Gossypium stocksii genome as a novel resource for cotton improvement

Cotton is an important textile crop whose gains in production over the last century have been challenged by various diseases. Because many modern cultivars are susceptible to several pests and pathogens, breeding efforts have included attempts to introgress wild, naturally resistant germplasm into elite lines. Gossypium stocksii is a wild cotton species native to Africa, which is part of a clade of vastly understudied species. Most of what is known about this species comes from pest resistance surveys and/or breeding efforts, which suggests that G. stocksii could be a valuable reservoir of natural pest resistance. Here we present a high-quality de novo genome sequence for G. stocksii. We compare the G. stocksii genome with resequencing data from a closely related, understudied species (G. somalense) to generate insight into the relatedness of these cotton species. Finally, we discuss the utility of the G. stocksii genome for understanding pest resistance in cotton, particularly resistance to cotton leaf curl virus.