Identification and Characterization of the DREB2C Drought-tolerant Gene in Peanut Cultivar L14 and Genetic Diversity Assessment of Some Peanut Cultivars based on SSR Markers Linked to Drought Tolerance

Abstract

Background: Peanut is a widely cultivated food crop of the legume family and is a major source of vegetable oil and protein in the global agricultural economy. However, the productivity of peanuts is severely affected by abiotic stress, particularly drought. Therefore, it is necessary to identify genes related to abiotic stress tolerance and analyze genetic diversity by SSR markers related to drought tolerance in peanut varieties. Methods: PCR amplification was used for the isolation of the DREB2C gene. The DREB2C gene sequence was analyzed using bioinformatic tools to identify functional domains, 3D modeling structures and other important characteristics. RT-qPCR was performed to evaluate the expression level of the DREB2C gene in the different tissues of peanut cultivars. A phylogenetic tree was constructed based on SSR markers linked to drought tolerance to assess the genetic diversity among peanut cultivars. Result: The present study identified the DREB2C gene in peanut cultivar L14. The gene encodes a polypeptide chain of 492 amino acids lacking transmembrane domains and signal peptides and with a conserved domain (AP2/ERF) and DNA binding site. The 3D protein structure was predicted with high confidence using various tools. The gene expression was investigated in different tissues and at different growth and developmental stages, as well as in various cultivars. Based on SSR markers linked to drought tolerance, the study revealed that peanut cultivars in Vietnam exhibit a medium level of diversity. It may be suggested that cross-breeding between different groups may increase variability among crops, allowing the generation of dominant varieties with improved drought tolerance.