Cytosolic antioxidant enzymes are a target to give durable resistance to water stress in commercial plum trees. Diaz-Vivancos et al. show improved tolerance to moderate or severe drought in transgenic lines, correlating with reduced leaf-drop, better photosynthetic performance (PSII quantum yield) and a tighter control of water use efficiency.

Chlorophyll fluorescence parameters in leaves of non-transformed (WT) and transgenic (lines C3-1 and J8-1) plum plants under control conditions.
Chlorophyll fluorescence parameters in leaves of non-transformed (WT) and transgenic (lines C3-1 and J8-1) plum plants under control conditions. Image after Diaz-Vivancos et al. 2016.

The two lines transformed with multiple copies of superoxide dismutase and ascorbate peroxidase genes suggested an enhanced capacity to cope with drought-induced oxidative stress. The transformed lines may be a valuable rootstock for improving plum crop yields in adverse environments.