Drought is a major stressor on plants. The many ways plants adapt to survive a drought have long been understood, but new research is showing the surprising degree in which a plant’s genome plays an active role in responding to drought stress.

Pacific Southwest Research Station researchers are part of a collaborative team studying Valley oak (Quercus lobata) response to water deprivation. Within drought-stressed trees, more than 18,000 genes became less active, while more than 17,000 became more highly expressed. Effected genes were responsible for regulating such functions as metabolism, water transport and nutrient transfer.