Improvement of Groundnut for Fatty Acids using Marker Assisted Breeding Approaches

Abstract

The cultivated groundnut (Arachis hypogaea L.), is self-pollinated, allotetraploid (2n = 4x = 40) with a genome size of 2891 Mbp, originated through a single hybridization and polyploidization event. Groundnut oil comprises about 80 % unsaturated fatty acids (UFA) and 20% saturated fatty acid. Consuming oils with high levels of oleic acid is beneficial to human health because it reduces low-density lipoproteins, maintain high-density lipoprotein, slow down atherosclerosis, and reversing the inhibitory effect of insulin production. As a result, peanut oil with a high percentage of oleic acid is preferred, and the oil quality can be determined by the oleic acid and linoleic acid (O/L) ratio. Fatty acid composition of groundnut oil is an important trait from human nutrition point of view as well as oil stability during the storage. Fatty acid desaturase (FAD) enzyme facilitate the conversion of oleic acid to linoleic acid by adding double bond to oleic acid. This enzyme is coded by two homologous genes (ahFAD2A and ahFAD2B) located on A and B sub genomes. Groundnut breeding for foliar disease resistance with desirable fatty acid composition can help in getting improved varieties. In conventional breeding, selection for fatty acid composition is carried out in advance generations, thus requires huge resources to handle and more time. However, it is possible to reject large number of plants in early generations with use of makers associated with ahFAD2 mutant alleles, thus optimizing resources and time.