Physiological and metabolomic responses of the ethylene insensitive squash mutant etr2b to drought.

The squash gain-of-function mutant etr2b disrupts the ethylene-binding domain of ethylene receptor CpETR2B, conferring partial ethylene insensitivity, changes in flower and fruit development, and enhanced salt tolerance. In this paper, we found that etr2b also confers a growth advantage as well as a physiological and metabolomic response that make the mutant better adapted to drought. Mutant plants had a higher root and leaf biomass than WT under both well-watered and drought conditions, but the reduction in growth parameters in response to drought was similar in WT and etr2b.