ABSTRACT

Gossypium arboreum (Desi Cotton) holds a special place in cotton industry because of its inherent ability to withstand drought, salinity, and remarkable resistance to sucking pests and cotton leaf curl virus. However, it suffers yield losses due to weeds and bollworm infestation. Genetic modification of G. arboreum variety FBD-1 was attempted in the current study to combat insect and weedicide resistance by incorporating cry1Ac, cry2A and cp4-EPSPS genes under control of 35S promoter in two different cassettes using kanamycin and GUS as markers through Agrobacterium-mediated shoot apex cut method of cotton transformation. The efficiency of transformation was found to be 1.57%. Amplification of 1700 bp for cry1Ac, 167 bp for cry2A and 111 bp for cp4-EPSPS confirmed the presence of transgenes in cotton plants. The maximum mRNA expression of cry1Ac and cp4-EPSPS was observed in transgenic cotton line L3 while minimum in transgenic cotton line L1. The maximum protein concentrations of Cry1Ac, Cry2A and Cp4-EPSPS of 3.534 µg g⁻¹, 2.534 µg g⁻¹ and 3.58 µg-g⁻¹ respectively were observed for transgenic cotton line L3 as compared to control cotton line. On leaf-feed-based insect bioassay, almost 99% mortality was observed for Helicoverpa armigera on the transgenic cotton plant (L3). It completely survived the 1900 ml hectare⁻¹ glyphosate spray assay as compared to non-transgenic cotton plants. The necrotic spots appeared on the third day, leading to the complete death of control plants on the fifth day of assay. The successful multiple gene-stacking in G. arboreum FBD-1 variety could be further used for qualitative improvement of cotton fiber through plant breeding techniques.

摘要

Gossypium arboreum (Desi Cotton) 由于其固有的抗旱、抗盐能力以及对吸吮害虫和棉花卷叶病毒的显着抵抗力而在棉花工业中占有特殊的地位。然而，由于杂草和棉铃虫侵扰，它遭受产量损失。在当前的研究中尝试对G. arboreum品种 FBD-1 进行遗传修饰，通过在两个不同的盒中使用卡那霉素和 GUS 作为标记，通过农杆菌将受 35S 启动子控制的cry1Ac、cry2A和cp4 -EPSPS基因掺入来对抗昆虫和除草剂抗性-棉花转化介导的茎尖切割法。发现转化效率为1.57%。1700 bp 的扩增cry1Ac、cry2A 的167 bp 和cp4 -EPSPS 的111 bp证实了棉花植株中存在转基因。在转基因棉花品系 L3 中观察到cry1Ac和cp4 -EPSPS 的mRNA 表达最高，而在转基因棉花品系 L1 中最低。与对照棉花品系相比，转基因棉花品系 L3的 Cry1Ac、Cry2A 和 Cp4-EPSPS 的最大蛋白质浓度分别为 3.534 µg ^-1、2.534 µg ^-1和 3.58 µg-g ^-1。在基于叶饲料的昆虫生物测定中，观察到棉铃虫在转基因棉花植物 (L3) 上的死亡率几乎为 99% 。它完全存活了 1900 毫升公顷^-1草甘膦喷雾试验与非转基因棉花植物相比。坏死斑点出现在第三天，导致对照植物在测定的第五天完全死亡。G. arboreum FBD-1 品种成功的多基因叠加可进一步用于通过植物育种技术对棉花纤维进行定性改进。