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GFP fluorescence and GUS histochemical staining showing the expression of reporter genes in cotton fiber tissues of CFSP::GUS and CFSP::GFP transgenic plants. GFP fluorescence displayed by the transgenic cotton fiber tissues of (A) C30 (CelA1::GFP), (B) C31 (LTP::GFP) and (C) C32 (Fb late::GFP) transgenic plants. The dark, non- fluorescence fiber tissues were from null transgenic plants (labeled N). D-G, GUS histochemical staining of cotton fiber tissues harvested from individual transgenic plants of: (D) a T2 family showing the segregation of reporter gene; a T3 family from a homozygous transgenic T2 plant showing uniform and different levels of GUS gene expression at (E) mid and (F) later fiber developmental stages; (G) a T3 family from a homozygous null transgenic T2 plant showing no Gus gene activity in any of the T3 plants.
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Cotton is one of the most important cash crops in US agricultural industry. Environmental stresses, such as drought, high temperature and combination of both, not only reduce the overall growth of cotton plants, but also greatly decrease cotton lint yield and fiber quality. The impact of environmental stresses on fiber development is poorly underst...
Citations
... Compared with the control, the balling treatment group's boll number per plant, seed cotton yield, and lint yield of cotton were significantly higher. Cotton fiber quality is an important factor used to determine the economic benefits of cotton production (Chen and Burke, 2015), and previous research has shown that it is mainly determined by genetic factors (Ruan et al., 2004;Li et al., 2018). ...
Seed coating is the most important type of pretreatment. Since cotton is an important economic crop, the cost of its cultivation and the resulting economic benefits are undoubtedly important aspects to be considered. In recent years, the high cost of coating materials and complex production processes have prevented the widespread application of cotton seed coating. Moreover, cotton plants emerge from cotyledons, and the coating material on the seed coat does not play a role after the seed emerges. Given the above shortcomings, to adapt to the mechanized direct seeding method and to include a large number of fertilizers and fungicides, insecticides can be used together with the seed direct seeding into the soil; at the same time, this will improve the cotton seedling emergence rate, the physiological qualities of cotton seedlings after the emergence of cotton seedlings, and the resilience of cotton seedlings in the early stage of resistance ability. In this study, we devised a technique for balling cotton seeds employing components such as cassava starch, bentonite, diatomite, attapulgite, and seedling substrate. The compositional ratios of the method were determined via a growth chamber trial, and we evaluated its effect throughout the cotton reproductive period using field trials. The results showed that the emergence and emergence hole rates of the balled cotton seeds increased by 34.42% and 28.84%, respectively, compared with the uncoated control. In terms of cotton yield, the seed balling treatment increased the number of bolls per plant and the overall cotton yield. Seed balling technology is different from traditional seed pelleting or seed coating techniques. It gathers one or more seeds in seed balls, enabling the simultaneous sowing of multiple seeds of the same variety or different varieties in the same crop. Additionally, seed balls can encourage seeds to carry fertilizer and pesticides into the soil, further weakening soil-borne diseases and abiotic stresses, form a relatively stable internal environment in the soil, and ensure the germination of cotton seeds. Our findings provide a reference point to improve cotton seedling emergence through the utilization of this novel technology.
... The fiber development process is categorized into four steps: initiation, cell elongation, deposition of secondary cell wall, and the maturation of anthesis (Chen and Burke, 2015;Rehman and Farooq, 2019). Among these phases, fiber development is more sensitive against drought stress (Kolahi et al., 2020). ...
... The fiber development process is categorized into four steps: initiation, cell elongation, deposition of secondary cell wall, and the maturation of anthesis (Chen and Burke, 2015;Rehman and Farooq, 2019). Among these phases, fiber development is more sensitive against drought stress (Kolahi et al., 2020). ...
... First, the pBI121 binary vector was modified by replacing the 35S promoter with fiber-specific promoter expansin, which is induced during cotton fiber elongation. Plasmid clone containing DNA fragment of cotton fiber-specific Crop Science expansin promoter was kindly provided by Dr. Chen (Chen & Burke, 2015). Primers were designed to amplify expansin promoter, including over-hanging sequences for Gibson cloning into pBI121 vector (Table S1). ...
... Since transgenic plants grown in pots in greenhouse produced limited number of balls, we used only one developmental time point for RT-qPCR analysis to preserve developing balls for fiber analysis. The 14 DPA developmental time point was selected because it is within the expression range of expansin promoter reported before (Chen & Burke, 2015;Orford & Timmis, 1998), and it is close to transition to SCW deposition. The range of actin expression was broader between the transgenic plants than controls (Figure 1). ...
Cotton fibers are the world's most important renewable source of fiber for textile industry. The cell wall of cotton fiber determines fiber quality parameters for textile industry. The thickness of secondary cell wall and the fiber perimeter define the fineness and micronaire (MIC) of cotton fiber. The fineness of cotton fiber plays an important role in affecting the yarn quality. Actin cytoskeleton impacts the cell extension and shape, however how it affects secondary cell wall is unclear. We overexpressed the actin isovariant Gh_D04G0865 (previously shown mutation in this gene impaired fiber length) under fiber‐specific promoter in cotton. We obtained two independent transgenic lines. Fiber characteristics of their first‐generation progenies were evaluated by high volume instrument (HVI), advanced fiber information system (AFIS), Cottonscope, and Fourier‐transform infrared (FT‐IR) spectroscopy. Fiber of transgenic lines with excessive expression of actin showed significant reduction in MIC and fineness, while increase in strength. Seed index was increased in transgenic lines overexpressing actin. FT‐IR analysis detected changes in vibrations associated with crystalline cellulose. Taken together, our findings revealed that actin cytoskeleton may play roles in reducing fiber wall thickening process during secondary cell wall biosynthesis.
... Different fiber development stages are used to study different fiber quality traits. For example, fiber initiation and elongation usually affect the fiber length, while FS is more influenced by the secondary wall-thickening stage (Lee et al. 2007;Chen and Burke 2015;Chen et al. 2019;Patel et al. 2020). The main components of cotton fiber are cellulose, hemicellulose, and lignin. ...
Gossypium barbadense possesses a superior fiber quality because of its fiber length and strength. An in-depth analysis of the underlying genetic mechanism could aid in filling the gap in research regarding fiber strength and could provide helpful information for G. barbadense breeding. Three quantitative trait loci related to fiber strength were identified from a G. barbadense recombinant inbred line (PimaS-7 × 5917) for further analysis. RNA sequencing was performed in the fiber tissues of PimaS-7 × 5917 0-35 days post-anthesis. Four specific modules closely related to the secondary wall-thickening stage were obtained using weighted gene co-expression network analysis. In total, 55 genes were identified as differentially expressed from four specific modules. Gene Ontology and the Kyoto Encyclopedia of Genes and Genomes were used for enrichment analysis, and Gbar_D11G032910, Gbar_D08G020540, Gbar_D08G013370, Gbar_D11G033670 and Gbar_D11G029020 were found to regulate fiber strength by playing a role in the composition of structural constituents of cytoskeleton and microtubules during fiber development. qRT-PCR results confirmed the accuracy of the transcriptome data. This study provides a quick strategy for exploring candidate genes and provides new insights for improving fiber strength in cotton.
... Similar activity behavior is observed in promoters of chitinase-like protein (GhCTL) and TCP transcriptional factor (GbTCP), except for some additional activity in anthers, xylems or young cotyledons and roots [7,8]. In addition, the regulatory sequences of RAC13, CelA1 and LTP also have activity in fibers of the elongation and secondary cell wall synthesis stages [9]. ...
Cotton fibers, single seed trichomes derived from ovule epidermal cells, are the major source of global textile fibers. Fiber-specific promoters are desirable to study gene function and to modify fiber properties during fiber development. Here, we revealed that Rho-related GTPase6 (GhROP6) was expressed preferentially in developing fibers. A 1240 bp regulatory region of GhROP6, which contains a short upstream regulatory sequence, the first exon, and the partial first intron, was unexpectedly isolated and introduced into transgenic cotton for analyzing promoter activity. The promoter of GhROP6 (proChROP6) conferred a specific expression in ovule surface, but not in the other floral organs and vegetative tissues. Reverse transcription PCR analysis indicated that proGhROP6 directed full-length transcription of the fused ß-glucuronidase (GUS) gene. Further investigation of GUS staining showed that proChROP6 regulated gene expression in fibers and ovule epidermis from fiber initiation to cell elongation stages. The preferential activity was enriched in fiber cells after anthesis and reached to peak on flowering days. By comparison, proGhROP6 was a mild promoter with approximately one-twenty-fifth of the strength of the constitutive promoter CaMV35S. The promoter responded to high-dosage treatments of auxin, gibberellin and salicylic acid and slightly reduced GUS activity under the in vitro treatment. Collectively, our data suggest that the GhROP6 promoter has excellent activity in initiating fibers and has potential for bioengineering of cotton fibers.
... Successful fertilization initiates boll formation, which overlaps with the seed and fiber development. The process of fiber development consisted of four overlapping stages i.e. fiber initiation (starts after 2 days of anthesis), fiber cell elongation (0-21 days after anthesis), secondary cell wall deposition (15-28 days of anthesis), and maturation (35-50 days after anthesis) (Chen and Burke, 2015;Rehman and Farooq, 2019). Out of these four stages, the first three are highly sensitive to abiotic stresses especially drought (Kolahi et al., 2020;Witt et al., 2020). ...
Climate change has increased the frequency and intensity of abiotic stresses, especially drought has become the major threat to cotton production worldwide due to long and intense dry spells in many cotton growing areas. Drought stress curtails the photosynthesis, carbohydrate metabolism (starch, sucrose synthesis), activities of several enzymes including vacuolar invertase and sucrose synthase, etc., which are involved in fiber development. Moreover, drought stressed cotton plant has poor assimilate translocation towards reproductive tissues, leading to poor pollen functioning, reproductive failure, and inferior fiber quality. The development of drought tolerant cotton genotypes using transgenes or QTL based molecular breeding approaches has proved effective in improving drought tolerance and fiber quality in cotton. The use of plant growth regulators and mineral elements can also aid in enhancing drought stress tolerance, fiber yield, and quality of cotton through initiating stress response related signaling cascades. Although, effects of drought stress in cotton are well reported, but variations in fiber quality due to the drought are not well explored. During the last few years, progress has been observed to understand these mechanisms which are critically reviewed here. This review highlights the water deficit stress induced habitual, physiological and biochemical changes during the reproductive growth leading to poor development of fiber. It also highlights the effect of drought stress on assimilate accumulation and portioning in reproductive tissues of cotton which finally converts into the fiber. This review will help devise new research to mitigate the negative impact of global climate change on world cotton production and fiber quality.
... It has been reported that the first three stages of fiber development are hypersensitive to environmental stress [5]. Extreme temperatures and other abiotic stresses during fiber development can significantly reduce cotton fiber yield and quality, and may even lead to falling bolls and squares [6][7][8]. ...
Gossypium barbadense is an important source of natural textile fibers, as is Gossypium hirsutum. Cotton fiber development is often affected by various environmental factors, such as abnormal temperature. However, little is known about the underlying mechanisms of temperature regulating the fuzz fiber initiation. In this study, we reveal that high temperatures (HT) accelerate fiber development, improve fiber quality, and induced fuzz initiation of a thermo-sensitive G. barbadense variety L7009. It was proved that fuzz initiation was inhibited by low temperature (LT), and 4 dpa was the stage most susceptible to temperature stress during the fuzz initiation period. A total of 43,826 differentially expressed genes (DEGs) were identified through comparative transcriptome analysis. Of these, 9667 were involved in fiber development and temperature response with 901 transcription factor genes and 189 genes related to plant hormone signal transduction. Further analysis of gene expression patterns revealed that 240 genes were potentially involved in fuzz initiation induced by high temperature. Functional annotation revealed that the candidate genes related to fuzz initiation were significantly involved in the asparagine biosynthetic process, cell wall biosynthesis, and stress response. The expression trends of sixteen genes randomly selected from the RNA-seq data were almost consistent with the results of qRT-PCR. Our study revealed several potential candidate genes and pathways related to fuzz initiation induced by high temperature. This provides a new view of temperature-induced tissue and organ development in Gossypium barbadense.
... This has been incredibly complemented by the RNAi technology in application of gene regulation [19]. This has opened new prospects for development of transgenic for over expression or silencing of a gene as per the requirement using small interfering RNA (siRNA)or artificial micro-RNA (amiRNA)based hairpin constructs in the industrial sector [20,21]. ...
... 1) are some of the areas where the genetic manipulation of plants can tremendously increase their commercial value and efficiency[20,22,23]. ...
In the present era of genomics, the genetic modification is no longer confined to species but has rather extended across genera. The research and development in the field of biotechnology has encompassed all spheres of biological sciences, despite all legal formalities and ethical issues associated with its commercial application. Industrial biotechnology is one such field where the biotechnological process is already being used and has been applied for commercial exploitation as the genetic modification does not directly apply to the food products. The potential industries for the development and application of genetic modifications are fiber, paper and pulp, timber, biofuels, pharmaceuticals products, vaccines and other industrial oils/fatty acids. This chapter reviews some of the major biotechnological interventions in these industrial sectors.
... All three e6l1 mutants showed a small reduction in the number of Col-0 pollen grains remaining adhered to the aniline blue-stained samples when compared to Col-0 stigmas and the reciprocal crosses (Col-0 stigmas pollinated with e6l1 mutant pollen); n = 10 stigmas for each cross. Letters represent statistically significant groupings of p < 0.05 based on a one-way ANOVA with Duncan post hoc tests for all samples elongation and cell-wall loosening (Chen and Burke 2015;Ji et al. 2003;Lee et al. 2006Lee et al. , 2007Li et al. 2002). One gene of particular note was the cotton orthologue of the Arabidopsis FIDDLEHEAD (FDH) gene which was found to be highly expressed in the developing cotton fibers (Lee et al. 2007;Li et al. 2002). ...
Key message
We describe a function for a novel Arabidopsis gene, E6-like 1 (E6L1), that was identified as a highly expressed gene in the stigma and plays a role in early post-pollination stages.
Abstract
In Arabidopsis, successful pollen–stigma interactions are dependent on rapid recognition of compatible pollen by the stigmatic papillae located on the surface of the pistil and the subsequent regulation of pollen hydration and germination, and followed by the growth of pollen tubes through the stigma surface. Here we have described the function of a novel gene, E6-like 1 (E6L1), that was identified through the analysis of transcriptome datasets, as one of highest expressed genes in the stigma, and furthermore, its expression was largely restricted to the stigma and trichomes. The first E6 gene was initially identified as a highly expressed gene during cotton fiber development, and related E6-like predicted proteins are found throughout the Angiosperms. To date, no orthologous genes have been assigned a biological function. Both the Arabidopsis E6L1 and cotton E6 proteins are predicted to be secreted, and this was confirmed using an E6L1:RFP fusion construct. To further investigate E6L1’s function, one T-DNA and two independent CRISPR-generated mutants were analyzed for compatible pollen–stigma interactions, and pollen hydration, pollen adhesion, and seed set were mildly impaired for the e6l1 mutants. This work identifies E6L1 as a novel stigmatic factor that plays a role during the early post-pollination stages in Arabidopsis.
