Drought response in global crops may be as complex as day and night
The research, appearing in the journal eLife, focuses on the plant’s response early in the drought stage.
By assessing change under less severe conditions, researchers hope to understand how plants respond to water stress in order to create more drought-resilient crops.
"This research considers all the factors in early drought response and may hopefully help us increase food production in the years to come."
For the study, researchers focused on Brassica rapa, a crop that provides Chinese cabbage, turnips and vegetable oil.
By tracking the plant’s reactions to water stress throughout the 48-hour period, the research team was able to identify nighttime plant activity indicating that Brassica may respond to early-stage drought by closing the stomata more fully at night.
"The increase in expression of genes for nitrogen uptake at night during early drought is especially intriguing" said Brent Ewers, a professor at the University of Wyoming and expert in plant physiological response to environmental stress, "this provides a potential mechanism to explain observations over the past 10 years that plants increase night water use when mildly to moderately stressed by lack of water and nutrients."
The combination of genetic and physiological information on how the plant responded to water conditions at different times of day could help researchers identify specific genes that respond more strongly to water conditions.
"Many genes are turned on or off at different times of the day based on the circadian clock," said McClung, an expert in genetics and circadian rhythms, "and we are trying to identify the small subset of genes that change specifically in response to drought."
We need to understand how plants respond to low water so that we can inform breeding to improve drought resistance."
While the research is still in its early stages, researchers hope that with continued success in identifying which genes are actually causing the changes that create drought response they can help plant breeders improve drought resistance more quickly and more precisely while potentially improving fertilization efficiency at the same time.