Elizabeth Castelbaum, Patrick Byrne, Martin Bjorn, Brett Carver, Mohamed Morgoum

Drought is one of the major abiotic factors affecting plant growth and crop production around the world. Consequently, there is a great need to develop more drought tolerant crops. Previous studies have shown that the accumulation of mannitol can help alleviate these effects by acting as an osmoprotectant and/or antioxidant. Transgenic wheat lines with mannitol 1-phosphate dehydrogenase (mtlD) derived from Escherichia coli accumulated mannitol and showed drought tolerance under greenhouse conditions. We conducted a two- year field trial under stressed and well watered conditions in Colorado. The first year results showed no significant improvement of the transgenic lines over the parental cultivar under either treatment. Results from the second year will be presented.