Overexpression of Pea DNA Helicase 45 (PDH45) imparts tolerance to multiple abiotic stresses in chili (Capsicum annuum L.)

Imparting tolerance to abiotic stresses is of global importance as they inflict significant yield losses in field as well as in vegetable crops. Transcriptional activators, including helicases are identified to play a pivotal role in stress mitigation. Helicases, also known as molecular motors, are involved in myriad cellular processes that impart intrinsic tolerance to abiotic stresses in plants. Our study demonstrates the potential of a Pea DNA Helicase 45 (PDH45), in combating multiple abiotic stresses in chili. We harnessed Agrobacterium-mediated in planta transformation strategy for the generation of stable, single copy transgenic events. Precise molecular detection of the transgenes by sqRT-PCR coupled with genomic Southern analysis revealed variation in the integration of PDH45 at distinct loci in independent transgenic events. Characterization of five promising transgenic events showed both improved response to an array of simulated abiotic stresses and enhanced expression of several stress-responsive genes. While survival and recovery of transgenic events were significantly higher under gradual moisture stress conditions, under imposition of moderate stress, the transgenic events exhibited invigorated growth and productivity with concomitant improvement in water use efficiency (WUE). Thus, our study, unequivocally demonstrated the cardinal role of PDH45 in alleviating multiple abiotic stresses in chili.