Expression Profiling of Flavonoid Biosynthetic Pathway Genes under the Effect of Drought and Salinity Stress

Abstract

Plants elaborate a vast array of important and chemically diverse natural products called flavonoids which play potential roles in their growth, development and defence against several abiotic stresses. The flavonoid biosynthetic pathway genes have been investigated under various studies in Arabidopsis, grape and Petunia. However, there have been very few studies conducted to understand the role of key flavonoid biosynthetic pathway genes in response to major abiotic stresses in agriculturally important crop, Arachis hypogaea (peanut). Therefore, there was a dire need to have an insight into the plant innate defence mechanisms for coping with environmental constraints. The present study was conducted on to understand the effects of two ruinous environmental stresses, salinity and drought on expression patterns of important genes (CHI, CHS, DFR, LAR, ANS, FLS and F3H) involved in flavonoid metabolism. The expression patterns of genes were significantly differed with respect imperative factors such as plant variety, stress type and the stress intensity. The study further demonstrated that the expression patterns are genotype dependent since few of the plant varieties demonstrated the highest induction of flavonoid pathway genes under mild stress while others under severe stress. The results provide valuable insight into the better understanding of flavonoid biosynthetic pathway in Arachis hypogea and serves as a reference data for other food crops as well.