Physiological responses to nitrate stress of transgenic tobacco plants harbouring the cucumber mitogen-activated protein kinase gene

Authors : Huini XU, Xudong SUN, Xiaoyu YANG, Qinghua SHI, Xiufeng WANG

Pages : 130-138

Doi:10.3906/bot-1110-27

View : 15 | Download : 9

Publication Date : 0000-00-00

Article Type : Research Paper

Abstract :The physiological responses to nitrate stress of 2 transgenic tobacco lines containing the cucumber mitogen-activated protein kinase insert ignore into journalissuearticles values(CsNMAPK); gene were investigated. Seed germination rates of the transgenic tobacco lines were higher than that of the wild type insert ignore into journalissuearticles values(WT); tobacco under 150 mM nitrate treatment. The transgenic seedlings had higher root fresh weight insert ignore into journalissuearticles values(FW); and dry weight insert ignore into journalissuearticles values(DW); than the WT plants after 98 mM and 182 mM nitrate treatment. The malondialdehyde insert ignore into journalissuearticles values(MDA); content, electrolytic leakage insert ignore into journalissuearticles values(EL);, and H2O2 content were higher in the WT than they were in the transgenic plants after 7-day nitrate stress treatment. The antioxidant enzyme insert ignore into journalissuearticles values(superoxide dismutase [SOD], catalase [CAT], peroxidase [POD], ascorbate peroxidase [APX]); activities increased with the increasing of nitrate concentration and the transgenic plants exhibited higher activities than the WT did. Excess nitrate stress induced more proline accumulation in the transgenic plants than in the WT plants. These results suggested that the tolerance of overexpressing-CsNMAPK tobacco plants to nitrate stress might partly be attributed to higher antioxidant enzyme activities and enhanced osmotic regulation capacity.
Keywords : Key words Mitogen activated protein kinase, cucumber, nitrate stress, antioxidant enzymes