Unfavorable environmental conditions represent considerable stress for plants. A high level of salt content (sodium chloride, NaCl) in the soil is just such a stressor that has a negative impact on plants. Salinization is a serious problem in agriculture especially in dry regions of the world. Biologists at the University of Münster have now discovered, for the first time, that salt stress triggers calcium signals in a special group of cells in plant roots, and that these signals form a "sodium-sensing niche." Also, the researchers identified a calcium-binding protein (CBL8) that contributes to salt tolerance specifically under severe salt stress conditions. The results of the study have now been published in the journal Developmental Cell.