Drought stress stunt tomato plant growth and up-regulate expression of SlAREB, SlNCED3, and SlERF024 genes

Tomato is an important agricultural crop and facing severe drought stress. PEG-6000 in five different concentrations was used to artificially induced drought stress in two tomato varieties; Nagina and 17905. The results demonstrated that seed germination significantly reduced upto 60% for variety Nagina at 8% PEG-6000. Other phenotypic traits such as shoot length, leaf length, leaves number and leaf area also reduced with increasing concentration of PEG-6000, however, root length increased with increasing PEG-6000 concentration. Fresh biomass for both varieties was found maximum as 1.51 g and 2.50 g at 2% PEG-6000 and minimum as 1.20 g and 1.14 g at 8% PEG-6000, respectively. However, Nagina variety showed more tolerance than variety 17,905 at different PEG-6000 concentrations. At molecular level, the three selected genes i.e. SlAREB, SlNCED3, and SlERF024 were found to be over expressed with increasing concentration of PEG-6000. In silico characterization of these genes revealed important conserved protein domains, involved in the drought stress. These results concurred to conclude that the different concentrations of PEG-6000 induced drought stress in tomato plant and SlAREB, SlNCED3, SlERF024 could be used to produce drought tolerant tomato varieties through plant transformation. (C) 2015 Elsevier B.V. All rights reserved.