Cotton fiber is multigenic trait controlled by number of genes. Previous studies suggest that one of these genes may be responsible for switching cotton fiber growth on and off to influence the fiber quality produced from a cotton seed. In the present study, the Gossypium hirsutum GhEXPA8 fiber expansin gene was introduced into local cotton variety NIAB 846 by using an Agrobacterium-mediated gene transformation. The neomycin phosphotransferase (NPTII) gene was used as a selection marker for screening of putative transgenic cotton plants. Integration and expression of the fiber expansin gene in cotton plants was confirmed with molecular techniques including Southern blot analyses, real-time PCR. Cellulose assay was used for measurement of cellulose contents of transgenic cotton fiber. The data collected from 3 years of field performance of the transgenic cotton plants expressing GhEXPA8 showed that significant improvement has been made in fiber lengths and micronaire values as compared to control G. hirsutum variety NIAB 846 cotton plants. Statistical techniques were also used for analysis of fiber and agronomic characteristics. The results of this study support improvement of cotton fiber through genetic modification.

More than 50 countries around the globe cultivate cotton on a large scale. It is a major cash crop of Pakistan and is considered “white gold” because it is highly important to the economy of Pakistan. In addition to its importance, cotton cultivation faces several problems, such as insect pests, weeds, and viruses. In the past, insects have been controlled by insecticides, but this method caused a severe loss to the economy. However, conventional breeding methods have provided considerable breakthroughs in the improvement of cotton, but it also has several limitations. In comparison with conventional methods, biotechnology has the potential to create genetically modified plants that are environmentally safe and economically viable. In this study, a local cotton variety VH 289 was transformed with two Bt genes (Cry1Ac and Cry2A) and a herbicide resistant gene (cp4 EPSPS) using the Agrobacterium mediated transformation method. The constitutive CaMV 35S promoter was attached to the genes taken from Bacillus thuringiensis (Bt) and to an herbicide resistant gene during cloning, and this promoter was used for the expression of the genes in cotton plants. This construct was used to develop the Glyphosate Tolerance Gene (GTGene) for herbicide tolerance and insecticidal gene (Cry1Ac and Cry2A) for insect tolerance in the cotton variety VH 289. The transgenic cotton variety performed 85% better compared with the non-transgenic variety. The study results suggest that farmers should use the transgenic cotton variety for general cultivation to improve the production of cotton.

BackgroundCotton yield has been badly affected by different insects and weed competition. In Past Application of multiple chemicals is required to manage insects and weed control was achieved by different conventional means, such as hand weeding, crop rotation and polyculture, because no synthetic chemicals were available. The control methods shifted towards high input and target-oriented methods after the discovery of synthetic herbicide in the 1930s. To utilise the transgenic approach, cotton plants expressing the codon-optimised CEMB GTGene were produced in the present study.ResultsLocal cotton variety CEMB-02 containing Cry1Ac and Cry2A in single cassette was transformed by synthetic codon-optimised 5-enolpyruvylshikimate-3-phosphate synthase gene cloned into pCAMBIA 1301 vector under 35S promoter with Agrobacterium tumifaciens. Putative transgenic plants were screened in MS medium containing 120 µmol/L glyphosate. Integration and expression of the gene were evaluated by PCR from genomic DNA and ELISA from protein. A 1.4-kb PCR product for Glyphosate and 167-bp product for Cry2A were obtained by amplification through gene specific primers. Expression level of Glyphosate and Bt proteins in two transgenic lines were recorded to be 0.362, 0.325 µg/g leaf and 0.390, 0.300 µg/g leaf respectively. FISH analysis of transgenic lines demonstrates the presence of one and two copy no. of Cp4 EPSPS transgene respectively. Efficacy of the transgene Cp4 EPSPS was further evaluated by Glyphosate spray (41 %) assay at 1900 ml/acre and insect bioassay which shows 100 %mortality of insect feeding on transgenic lines as compared to control.ConclusionThe present study shows that the transgenic lines produced in this study were resistant not only to insects but also equally good against 1900 ml/acre field spray concentration of glyphosate.Electronic supplementary materialThe online version of this article (doi:10.1186/s13104-015-1397-0) contains supplementary material, which is available to authorized users.