Assistant Professor of Plant Physiology University of Maine Orono, Maine, United States
Abstract: The wild lowbush blueberry, one of the few North American native fruit crops, is facing a growing threat from summer droughts. As a natural system, wild blueberry plants typically grow in fields without irrigation, making them vulnerable to water shortages. To assess their sensitivity to drought, we conducted controlled experiments and analyzed historical remote sensing data. Our drought experiment revealed that wild blueberry plants have a conservative water use strategy, with photosynthesis and stomatal conductance showing high sensitivity to drought. They also dropped leaves quickly, and stem dieback was also observed under severe drought treatment. Interestingly, wild blueberry plants can recover from drought by resprouting from belowground biomass. Thus, our results suggest that wild blueberry plants are resilient to drought and are able to recover from resprouting even after severe drought. This also suggests a strategy of sacrificing aboveground biomass in coping with drought stress for this shrub species. This agrees with our remote sensing data showing the yield and vegetation index of this species is rather sensitive to drought. We conclude that wild blueberry plants are resilient to drought, but their berry yield is sensitive to drought. Our results ask for drought mitigation techniques for this traditional agricultural system under climate change with increasing drought.
