Abstract: Methods of producing transgenic photosynthetic organisms and plants overexpressing an FMO protein are disclosed. The disclosure also relates to transgenic photosynthetic organisms and plants having between 4 and 37 fold greater expression of an FMO protein compared to wild-type plants, wherein said transgenic photosynthetic organisms and plants have between 1.1 and 3.4 fold greater trimethylamine N-oxide compared to wild-type, and wherein said transgenic photosynthetic organisms plants are drought tolerant. The disclosure further relates to DNA constructs and methods of producing DNA constructs having a promoter operably linked to one or more FMO protein coding sequences. The disclosure further relates to methods of producing drought tolerant plants and photosynthetic organisms by applying an effective amount of trimethylamine N-oxide di-hydrate.

Abstract: A method for increasing drought tolerance in a plant or photosynthetic organism is provided, where the tolerance is increased by applying an effective amount of trimethylamine N-oxide (TMAO) or trimethylamine N-oxide di-hydrate, or a TMAO chemical derivative, or a TMAO chemical analog and thereof to a plant, seed or photosynthetic organism that has been exposed to or to be exposed to water stress conditions. Water stress tolerant plants or photosynthetic organisms produced through the application of trimethylamine N-oxide (TMAO) or trimethylamine N-oxide di-hydrate, or a TMAO chemical derivative, or a TMAO chemical analog to a plant or photosynthetic organism are also disclosed.

Abstract: A method for increasing drought tolerance in a plant or photosynthetic organism is disclosed, where the tolerance is increased by introducing nucleic acid sequences coding for polypeptides with monooxigenase activity or by the modification of endogenous nucleic acid sequences that increase the endogenous TMAO content in plants as well as to nucleic acid constructs, recombinant vectors, cells, transgenic plants, crops, propagation material, compositions and harvestable parts of a plant comprising nucleic acid sequences in order to increase water stress tolerance and so on.