Stacked Genes Enhances Drought Tolerance in Maize

Genetic engineering is constantly being used to develop stress resistance genes for crops. Previous studies have shown that genes betA and TsVP are effective sources of tolerance to drought. betA encodes choline dehydrogenase, a key enzyme in the production of glycine betaine which is a natural compound used by plants for protection against drought stress; while TsVP encodes for V-H⁺-PPase or vacuolar H⁺ pyrophosphatase, an enzyme that directly transduce the energy for tonoplast transport. AiYing Wei from Shangdong University, China, together with other scientists, crossed two transgenic maize lines, one with betA gene, while the other with TsVP gene to produce a maize offspring with both drought tolerance genes. Analysis confirmed the expression of the two genes in the offspring.

The maize offspring produced higher glycine betaine levels and H⁺-PPase activity, compared to the parental lines. Furthermore, less cell damage was observed in these plants and exhibited higher yields than parental lines when exposed to stress.  This research open possibilities in the development of stress tolerance in other crop varieties.

 Read the abstract at http://onlinelibrary.wiley.com/doi/10.1111/j.1467-7652.2010.00548.x/abstract.