Abstract:

Plant genetic engineering was widely used to improve crop viability and tolerance to environmental stresses. In this report,an OsVTE gene was introduced into Cichorium intybus L. ‘Puna’ by Agrobacterium-mediation transformtion. Transgenic chicory plants were obtained under Kanamycin selection, and confirmed by PCR and Southern-blot tests. Effects of different concentrations of sucroses, agarose and mannitol were used as a mimic of drought stress codiction to investigate drought tolerance of chicory seedlings. The results showed that drought tolerance of transgenic plants was better than those non-transgenic ones. Activity of peroxidase (POD) and superocide (SOD) dismutase of transgenic seedings at the sucrose concentration of 50 g·L^-1, agarose concentration of 10 g·L^-1 and mannitol concentration of 30 g·L^-1 was 2~3 times higher than that of non-transgenic ones. Malonaldehyde (MDA) content in transgenic seedlings was lower than that of non-transgenci ones. Overall, stable transgenic plants with OsVTE were obtained. The transgenic plants showed higher drought tolerance, content of POD and SOD dismutase in transgenic plants was increased under drought stress conditions.

Key words: Tocopherol cyclase gene (OsVTE), Cichorium intybus L.‘Puna’, Agrobacterium-mediated, Genetic transformation, Stress tolerance

摘要：

通过植物基因工程手段培育转基因作物品种，可改善作物的生存能力和对生态环境的耐受力。本研究以普那菊苣叶片（Cichorium intybus L.‘Puna’）为受体材料，用农杆菌介导方法，将来自水稻的由CaMV35S启动子驱动的生育酚环化酶（tocopherol cyclase，OsVTE）基因导入普那菊苣。经过卡那霉素（Km）筛选以及对抗性植株PCR和Southern杂交分析，获得了转基因植株。用不同浓度的蔗糖、琼脂和甘露醇溶液研究普那菊苣幼苗的耐旱性，发现转基因植株的耐旱性明显得到提高。蔗糖浓度为50 g·L^-1、琼脂浓度为10 g·L^-1和甘露醇浓度为30 g·L^-1胁迫下普那菊苣的生理指标测定显示，转基因普那菊苣幼苗SOD、POD活性比未转化植株高2~3倍，转基因普那菊苣幼苗MDA含量降低。本研究获得了稳定的转OsVTE基因植株，旱胁迫下的转基因植株的SOD酶活性和POD酶活性含量提高，表现出一定的耐旱性。

关键词: 维生素E(OsVTE), 普那菊苣, 农杆菌介导, 遗传转化, 抗逆性