Search

Abstract Background Gossypium hirsutum undergoes rapid clonal propagation to regenerate a mature plant through tissue culture. However, the correlation between cotton leaf regeneration, callus induction, and regeneration ability was still obscure. In this research, cotton leaf regeneration level for 21 accessions in the field (new leaves) was observed after the first harvest, and a comparison between field regeneration level and callus induction with its regeneration capacity (new shoots and roots) for the same 21 accessions was carried out. Agronomic traits, including plant height, leaf area, fresh leaf weight, dry leaf weight, the number of flowers and bolls, and biochemical (proline content) and physiological (chlorophyll and carotenoid content) traits during the flowering stage of 21 upland cotton accessions, were investigated. Result A significant correlation between physiological parameters and callus induction was discovered. Callus induction and regeneration capacity of roots and shoots for hypocotyl, cotyledons, and shoot tip tissues were used to validate field leaf regeneration level after the first harvest. CCRI 24 showed significant leaf regeneration in the field and callus induction capacity through callus induction and regeneration. Conclusion We found a substantial relationship between field regeneration capability and callus induction with its regeneration capacity for the hypocotyl, cotyledons, and shoot tip. The results showed that ZS061, Lumian 378, Jimian 863, and ZS065 have the highest moisture retention capacity, while CCRI 24, Liaoyang Duomaomian, and Beizhe Gongshemian have the lowest moisture retention capacity. CCRI 24 has the highest leaf regeneration capacity in the field, while Beizhe Gongshemian has the lowest leaf regeneration capacity. All our result provides a clue for checking the regeneration capacity through leaf regeneration level in the field.

Abstract Background ORP (Oxysterol-binding protein-related proteins) genes play a role in lipid metabolism, vesicular transferring and signaling, and non-vesicular sterol transport. However, no systematic identification and analysis of ORP genes have been reported in cotton. Result In this study, we identified 14, 14, 7, and 7 ORP genes in G. hirsutum, G. barbadense, G. arboreum, and G. raimondii, respectively. Phylogenetic analysis showed that all ORP genes could be classified into four groups. Gene structure and conserved motif analysis suggest that the function of this gene family was conserved. The Ka/Ks analysis showed that this gene family was exposed to purifying selection during evolution. Transcriptome data showed that four ORP genes, especially GhORP_A02, were induced by abiotic stress treatment. The cis-acting elements in the ORP promoters were responsive to phytohormones and various abiotic stresses. The silenced plants of GhORP_A02 were more sensitive to drought stress when compared to control. Conclusion The major finding of this study shed light on the potential role of ORP genes in abiotic stress and provided a fundamental resource for further analysis in cotton.

Abstract Background The cotton crop is universally considered as protein and edible oil source besides the major contributor of natural fiber and is grown in tropical and subtropical regions around the world Unpredicted environmental stresses are becoming significant threats to sustainable cotton production, ultimately leading to a substantial irreversible economic loss. Mitogen-activated protein kinase (MAPK) is generally considered essential for recognizing environmental stresses through phosphorylating downstream signal pathways and plays a vital role in numerous biological processes. Results We have identified 74 MAPK genes across cotton, 41 from G. hirsutum, 19 from G. raimondii, whereas 14 have been identified from G. arboreum. The MAPK gene-proteins have been further studied to determine their physicochemical characteristics and other essential features. In this perspective, characterization, phylogenetic relationship, chromosomal mapping, gene motif, cis-regulatory element, and subcellular localization were carried out. Based on phylogenetic analysis, the MAPK family in cotton is usually categorized as A, B, C, D, and E clade. According to the results of the phylogenic relationship, cotton has more MAPKS genes in Clade A than Clade B. The cis-elements identified were classified into five groups (hormone responsiveness, light responsiveness, stress responsiveness, cellular development, and binding site). The prevalence of such elements across the promoter region of these genes signifies their role in the growth and development of plants. Seven GHMAPK genes (GH_A07G1527, GH_D02G1138, GH_D03G0121, GH_D03G1517, GH_D05G1003, GH_D11G0040, and GH_D12G2528) were selected, and specific tissue expression and profiling were performed across drought and salt stresses. Results expressed that six genes were upregulated under drought treatment except for GH_D11G0040 which is downregulated. Whereas all the seven genes have been upregulated at various hours of salt stress treatment. Conclusions RNA sequence and qPCR results showed that genes as differentially expressed across both vegetative and reproductive plant parts. Similarly, the qPCR analysis showed that six genes had been upregulated substantially through drought treatment while all the seven genes were upregulated across salt treatments. The results of this study showed that cotton GHMPK3 genes play an important role in improving cotton resistance to drought and salt stresses. MAPKs are thought to play a significant regulatory function in plants' responses to abiotic stresses according to various studies. MAPKs' involvement in abiotic stress signaling and innovation is a key goal for crop species research, especially in crop breeding.

Root system architecture (RSA) is the primary predictor of nutrient intake and significantly influences potassium utilization efficiency (KUE). Uncertainty persists regarding the genetic factors governing root growth in rapeseed. The root transcriptome analysis reveals the genetic basis driving crop root growth. In this study, RNA-seq was used to profile the overall transcriptome in the root tissue of 20 Brassica napus accessions with high and low KUE. 71,437 genes in the roots displayed variable expression profiles between the two contrasting genotype groups. The 212 genes that had varied expression levels between the high and low KUE lines were found using a pairwise comparison approach. The Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) functional classification analysis revealed that the DEGs implicated in hormone and signaling pathways, as well as glucose, lipid, and amino acid metabolism, were all differently regulated in the rapeseed root system. Additionally, we discovered 33 transcription factors (TFs) that control root development were differentially expressed. By combining differential expression analysis, weighted gene co-expression network analysis (WGCNA), and recent genome-wide association study (GWAS) results, four candidate genes were identified as essential hub genes. These potential genes were located fewer than 100 kb from the peak SNPs of QTL clusters, and it was hypothesized that they regulated the formation of the root system. Three of the four hub genes’ homologs—BnaC04G0560400ZS, BnaC04G0560400ZS, and BnaA03G0073500ZS—have been shown to control root development in earlier research. The information produced by our transcriptome profiling could be useful in revealing the molecular processes involved in the growth of rapeseed roots in response to KUE.

Abstract Background Cotton production is adversely effected by drought stress. It is exposed to drought stress at various critical growth stages grown under a water scarcity environment. Roots are the sensors of plants; they detect osmotic stress under drought stress and play an important role in plant drought tolerance mechanisms. The seedling stage is very sensitive to drought stress, and it needed to explore the methods and plant characteristics that contribute to drought tolerance in cotton. Results Initially, seedlings of 18 genotypes from three Gossypium species: G. hirsutum, G. barbadense, and G. arboreum, were evaluated for various seedling traits under control (NS) and drought stress (DS). Afterward, six genotypes, including two of each species, one tolerant and one susceptible, were identified based on the cumulative drought sensitivity response index (CDSRI). Finally, growth rates (GR) were examined for shoot and root growth parameters under control and DS in experimental hydroponic conditions. A significant variation of drought stress responses was observed across tested genotypes and species. CDSRI allowed here to identify the drought-sensitive and drought-resistant cultivar of each investigated species. Association among root and shoots growth traits disclosed influential effects of enduring the growth under DS. The traits including root length, volume, and root number were the best indicators with significantly higher differential responses in the tolerant genotypes. These root growth traits, coupled with the accumulation of photosynthates and proline, were also the key indicators of the resistance to drought stress. Conclusion Tolerant genotypes have advanced growth rates and the capacity to cop with drought stress by encouraging characteristics, including root differential growth traits coupled with physiological traits such as chlorophyll and proline contents. Tolerant and elite genotypes of G. hirsutum were more tolerant of drought stress than obsolete genotypes of G. barbadense and G. arboreum. Identified genotypes have a strong genetic basis of drought tolerance, which can be used in cotton breeding programs.

Cotton is an important natural fiber crop; its seeds are the main oil source. Abiotic stresses cause a significant decline in its production. The WUSCHEL-related Homeobox (WOX) genes have been involved in plant growth, development, and stress responses. However, the functions of WOX genes are less known in cotton. This study identified 39, 40, 21, and 20 WOX genes in Gossypium hirsutum, Gossypium barbadense, Gossypium arboreum, and Gossypium raimondii, respectively. All the WOX genes in four cotton species could be classified into three clades, which is consistent with previous research. The gene structure and conserved domain of all WOX genes were analyzed. The expressions of WOX genes in germinating hypocotyls and callus were characterized, and it was found that most genes were up-regulated. One candidate gene Gh_ A01G127500 was selected to perform the virus-induced gene silencing (VIGS) experiment, and it was found that the growth of the silenced plant (pCLCrVA: GhWOX4_A01) was significantly inhibited compared with the wild type. In the silenced plant, there is an increase in antioxidant activities and a decrease in oxidant activities compared with the control plant. In physiological analysis, the relative electrolyte leakage level and the excised leaf water loss of the infected plant were increased. Still, both the relative leaf water content and the chlorophyll content were decreased. This study proved that WOX genes play important roles in drought stress and callus induction, but more work must be performed to address the molecular functions of WOX genes.

Protein phosphorylation, one of the major post-translational modifications, plays a crucial role in cell signaling, DNA replication, gene expression and differentiation; and alters enzyme activity and other biological activities; and regulates cell proliferation and enlargement, phytohormone biosynthesis and signaling, plant disease resistance, and grain filling and quality during rice seed development. Research work on protein phosphorylation started in the 1950s with the discovery of phosphorylase a and phosphorylase b which are phospho and dephospho forms of the same enzyme. Over the last decade, rice proteomics has accomplished tremendous progress in setting up techniques to proteome nearly all tissues, organs and organelles. The progress made in this field is evident in number of research works. However, research on rice protein phosphorylation is still at its infancy and there are still many unanswered questions. In this review, the general description of protein phosphorylation, including history, structure, frequency of occurrence and function, are discussed. This work also elucidates the different methods for identification, qualification and finally, the progress in rice phosphoproteome research and perspectives. Keywords: phosphoproteome, protein phosphorylation, post-translational modification, rice

Cotton production is hampered by a variety of abiotic stresses that wreak havoc on the growth and development of plants, resulting in significant financial losses. According to reports, cotton production areas have declined around the world as a result of the ongoing stress. Therefore, plant breeding programs are concentrating on abiotic stress-tolerant cotton varieties. Mitogen-activated protein kinase (MAPK) cascades are involved in plant growth, stress responses, and the hormonal signaling pathway. In this research, three abiotic stresses (cold, drought, and salt) were analyzed on GhMPK3 transformed Arabidopsis plants. The transgenic plant’s gene expression and morphologic analysis were studied under cold, drought, and salt stress. Physiological parameters such as relative leaf water content, excised leaf water loss, chlorophyll content, and ion leakage showed that overexpressed plants possess more stable content under stress conditions compared with the WT plants. Furthermore, GhMPK3 overexpressed plants had greater antioxidant activities and weaker oxidant activities. Silencing GhMPK3 in cotton inhibited its tolerance to drought stress. Our research findings strongly suggest that GhMPK3 can be regarded as an essential gene for abiotic stress tolerance in cotton plants.