Cotton Acquires Improved Drought Tolerance by Overexpressing the TaMnSOD Gene

Cotton (Gossypium hirsutum L.) is considered a drought tolerant crop. However, tolerance differs greatly across cotton genotypes. Hence, it is imperative to improve its drought tolerance. A gene from Tamarix androssowii, an extremely drought tolerant shrub in Xinjiang, China, may provide us with the solution.

In a previous study, transgenic poplars overexpressing the T. androssowii gene, TaMnSOD, have showed improved drought tolerance. Based on these previous studies, TaMnSOD was introduced and then overexpressed in cotton to create several independent transgenic lines. The transgenic lines and control plants were evaluated and compared their stress-related physiological and biochemical parameters under water deficit conditions in a growth chamber. Morphological traits were also observed after recovery from water-withholding stress.

Transgenics had improved antioxidant enzyme activity and cell membrane integrity. Furthermore, net photosynthesis, stomatal conductance, and transpiration rate were also increased in transgenic plants. Transgenic cotton also showed increased biomass and root and leaf systems compared to wild types after 2 weeks recovery from drought stress.

For more information regarding this study, feel free to visit http://link.springer.com/article/10.1007/s11032-014-0015-5/fulltext.html.