Phytoextraction Potential of Wild Type and 35S-GSHI Transgenic Poplar Trees (Populus × Canescens) for Environmental Pollutants Herbicide Paraquat, Salt Sodium, Zinc Sulfate and Nitric Oxide In Vitro

Abstract

Phytoextraction potentials of two transgenic (TR) poplar (Populus × canescens) clones TRggs11 and TRlgl6 were compared with that of wild-type (WT) following exposure to paraquat, zinc sulfate, common salt and nitric oxide (NO), using a leaf-disc system incubated for 21 days on EDTA-containing nutritive WPM media in vitro. Glutathione (GSH) contents of leaf discs of TRlgl6 and TRggs11 showed increments to 296% and 190%, respectively, compared with WT. NO exposure led to a twofold GSH content in TRlgl6, which was coupled with a significantly increased sulfate uptake when exposed to 10−3 M ZnSO4. The highest mineral contents of Na, Zn, Mn, Cu, and Mo was observed in the TRggs11 clone. Salt-induced activity of catalase enzyme increased in both TR clones significantly compared with WT under NaCl (0.75% and 1.5%) exposure. The in silico sequence analyses of gsh1 genes revealed that P. × canadensis and Salix sachalinensis show the closest sequence similarity to that of P. × canescens, which predicted an active GSH production with high phytoextraction potentials of these species with indication for their use where P. × canescens can not be grown.