Expression analysis of stress responsive transcription factors during heat, drought and salinity tolerance in wheat

A Wheat (Triticum aestivum L.) is one of the most important staple crops for the global population. It feeds about 40 % of the world population by providing 20 % of total food calories and protein in human diet. It is highly challenged by various abiotic stresses such as drought, salt and heat stress during different growth and developmental stages leading to decreased total production. By altering physiological and metabolic processes, heat, salt and drought stress embarks major threat to the vegetative stage of plant growth and development (Boyer 1982). These stresses continue to be an important challenge to agricultural scientists to develop high performing genotypes. Plants response to heat, salinity and drought is highly negotiated by genotype, growth and developmental stage, duration of exposure, physiological, biochemical and molecular process leading to differential reprogramming of gene expressions (Chaves et al., 2003; Denby and Gehring, 2005; Flowers 2004; Langridge et al., 2006). Among the most important regulatory molecules, DREB family members are central in the regulation of effector molecules. DREB genes, found to be involved in stress signal transduction pathways (Ishitani et al., 1997; Knight et al., 1999; Lee et al., 2001), belong to a large DNA-binding protein family containing a conserved EREBP/AP2 domain (Pandey et al., 2014; Pandey et al., 2016). Different members of this family are able to regulate different processes such as stress response, hormone response and plant development functioning as trans-acting factors in separate signal transduction pathways (Riechmann and Meyerowitz 1998). Similarly, other genes such as NAC, TIR and SCl have also been reported to be involved in modulating the different abiotic stress responses in plants (Puranik et al., 2012).