SUMO proteases play a vital role in regulating pathway flux and are therefore ideal targets for manipulating stressresponses. In the present study, the expression of an A. thaliana cysteine protease (OVERLY TOLERANT TO SALT-1, OTS1) in wheat (Triticum aestivum L.) has led to improved plant growth under water stress conditions. Transformed wheat (pUBIOTS1) and EMS mutants displayed enhanced growth under water deficit when compared with untransformed Gamtoos-R genotype or plants carrying an empty vector. Transformed pUBI-OTS1 plants and EMS mutants also maintained a high relative moisture content (RMC), had a higher photosynthesis rate, and also had a higher total chlorophyll content when compared to untransformed plants or plants carrying an empty vector. SUMOylation of total protein also increased in untransformed plants but not in the AtOTS1 transformed plants and EMS mutants, resulting in the delayed senescence under water stress conditions. Interestingly, the EMS mutants displayed two responses to drought, namely tolerance and avoidance (resurrection). Our results suggest that SUMO-proteases may influence an array of mechanisms in wheat to the advantage of the crop to be more tolerant to water stress caused by drought. This is the first report to elucidate SUMOylation effects in the hexaploid crop wheat (Triticum aestivum L.).