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.

► It is unclear how metabolic changes contribute to drought resistance.
► Arabidopsis is distributed across habitats that differ dramatically in water availability and uses primarily a low water potential/dehydration avoidance strategy to cope with water limitation.
► Natural variation in drought response is relatively uncharacterized but includes metabolic traits such as proline accumulation.
► Quantitative genetics combined with appropriate phenotypic data can be one avenue for identifying genes important for drought adaptation.