Drought, metabolites, and Arabidopsis natural variation: a promising combination for understanding adaptation to water-limited environments.

Drought elicits substantial changes in plant metabolism and it remains a challenge to determine which of these changes represent adaptive responses and which of them are merely neutral effects or even symptoms of damage. Arabidopsis primarily uses low water potential/dehydration avoidance strategies to respond to water limitation. The large variation in evolved stress responses among accessions can be a powerful tool to identify ecologically important and adaptive traits; however, collection of relevant phenotype data under controlled water stress is often a limiting factor. Quantitative genetics of Arabidopsis has great potential to find the genes underlying variation in drought-affected metabolic traits, for example proline metabolism, as well as overall adaptation.