Expression Profiling of Flavonoid Biosynthetic Genes in Arachis hypogaea Under Drought Stress

Abstract

Arachis hypogaea (peanut) is one of the important crops of family Leguminosae. It is a crop of semi-arid regions and its yield is affected by various environmental stresses specifically drought, leading to serious production losses. Better understanding of stress responses is critical to improve tolerant of crops. Two subclasses of flavonoids, flavonols and chalcones have diverse roles in plant defense and their synthesis is catalyzed by FLS and CHS respectively. CHS is the first enzyme that catalyzes flavonoid biosynthetic pathway while FLS catalyzes late reactions in this pathway. However, a little information about their behavior in peanut is available. In the present study, the expression of these two flavonoid biosynthetic genes is analyzed. Results indicated that RNA transcript level of both genes was up regulated under drought stress in peanut variety BARI-2011. The maximum RNA transcript level was after ten days under severe drought stress while maximum FLS expression was observed after ten days under of mild drought stress in set experimental conditions. Current study suggests the protective role of flavonoids against drought. However, functions of flavonoid biosynthetic genes involved in defense role against drought stress need further validation