Overexpression of Galactinol Synthase Gene Improves Drought Tolerance in Rice

Enhancing drought tolerance without grain yield penalty has been a challenge for plant breeders and crop improvement. A team of researchers from the International Center for Tropical Agriculture in Colombia, and various universities and research institutions in Japan evaluated the Arabidopsis thaliana galactinol synthase 2 gene (AtGolS2). The team overexpressed the gene in rice (Oryza sativa) to confer drought tolerance and increase grain yield under dry conditions.

The developed transgenic lines had higher levels of galactinol than non-transgenic plants. The transgenics also had increased grain yield under drought conditions, which is related to the higher number of panicles, grain fertility, and biomass. Extensive confined field trials of the transgenic lines across two seasons revealed that the lines have the proven field drought tolerance. The drought tolerance was found to be associated with a higher relative water content of leaves, higher photosynthesis activity, lesser reduction in plant growth and faster recovering ability.

These provide strong evidence that AtGolS2 is can be a useful tool to reduce grain yield losses in rice under field drought stress.

For more on the study, read the full article in Plant Biotechnology Journal.