Heterologous Expression of the AtDREB1A Gene in Transgenic Peanut-Conferred Tolerance to Drought and Salinity Stresses

Abstract

Research on genetic transformation in various crop plants using the DREB1A transcription factor has shown better abiotic stress tolerance in transgenic crops. The AtDREB1A transgenic peanut (Arachis hypogaea L. cv. GG 20), which was previously developed, was characterized in terms of its physio-biochemical, molecular and growth parameters. The tolerance of this transgenic peanut to drought and salinity stresses was evaluated at the seedling (18 days old) and maturity stages. Transgenic peanut lines showed improved tolerance to both stresses over wild-type, as observed by delayed and less severe wilting of leaves and by improved growth parameters that were correlated with physio-biochemical parameters such as proline content, total chlorophyll content, osmotic potential, electrolytic leakage and relative water content. The expression pattern of the AtDREB1A gene evaluated using qPCR at different time points demonstrated that transgene expression was induced within two hours of stress imposition. The better performance of transgenic AtDREB1A peanut at the seedling stage and the improved growth parameters were due to the expression of the transgene, which is a transcription factor, and the possible up-regulation of various stress-inducible, downstream genes in the signal transduction pathway under abiotic stress.

Insights into the Indian Peanut Genotypes for ahFAD2 Gene Polymorphism Regulating Its Oleic and Linoleic Acid Fluxes

“…fastigiata (Krapovickas and Rigoni, 1960). It is cultivated in more than 100 countries, mostly by the small and marginal farmers, under low-input conditions (Bhauso et al, 2014; Sarkar et al, 2014). Peanut is one among the major oilseed crops, which contribute to the bulk of total oil production worldwide (Mishra et al, 2015).…”

Expression of Pennisetum glaucum Eukaryotic Translational Initiation Factor 4A (PgeIF4A) Confers Improved Drought, Salinity, and Oxidative Stress Tolerance in Groundnut

“…It could be due to the positive regulation of rd29A promoter which involved in stress inducible expression of transgene. Similarly, higher expression of AtDREB1A was seen in groundnut transgenic plants which were regulated by rd29A promoter (Sarkar et al, 2014, 2016). It indicated that there was positive correlation between regulation of transgene and stress tolerance.…”

“…The genes from Salicornia brachiata, ascorbate peroxidase ( SbAPX ), and abscisic acid stress ripening ( SbASR ) genes when expressed in groundnut displayed salt and drought stress tolerance coupled with more chlorophyll retention and enhanced levels of relative water content under normal/stress conditions (Singh et al, 2014; Tiwari et al, 2015). The transcription factors from Arabidopsis, AtNAC2 (Patil et al, 2014), AtDREB1A (Sarkar et al, 2014, 2016) and horsegram, MuNAC4 (Pandurangaiah et al, 2014) were exhibited drought and salt stress tolerance in groundnut by reducing the membrane damage and improving scavenging of reactive oxygen species scavenging (ROS). Groundnut transgenic plants ( cv TMV-2) simultaneously expressing three TFs ( AtDREB2A, AtHB7 , and AtABF3 ) displayed to increase drought, salinity, and oxidative stress tolerance compared to wild type (Pruthvi et al, 2014).…”

Transgenic peanut overexpressing mtlD gene confers enhanced salinity stress tolerance via mannitol accumulation and differential antioxidative responses

“…India, peanut is mostly grown under rain-fed conditions, mostly by resource-poor farmers, and, hence, is most likely encountered by abiotic stresses like drought and salinity (Sarkar et al 2014;Bhauso et al 2014a, b).…”