Water is an increasingly scarce resource that limits crop productivity in many parts of the world, and the frequency and severity of drought are predicted to increase as a result of climate change. Improving tolerance to drought stress is therefore important for maximizing future crop yields.

Marquez-Garcia et al. study the effects of drought in leaves and nodules of soybean (Glycine max) and find that while the physiological impact is perceived throughout the shoot, stress-induced senescence occurs only in the oldest leaf ranks. A number of drought-induced changes in nodule metabolites are observed and transcripts of two peroxiredoxins are identified in nodules as potential markers for stress tolerance. They conclude that stress-induced senescence in the lowest leaf ranks precedes nodule senescence, suggesting that leaves of low photosynthetic capacity are sacrificed in favour of nodule nitrogen metabolism.
This article appears in the special issue ROS and NO Reactions in Plants.