Enhancing oleic acid content in two commercially released peanut varieties through marker‐assisted backcross breeding

Abstract

Two elite cultivars of peanut (Arachis hypogaea L.), GPBD 4 and G 2-52, with high productivity, oil content, resistance to late leaf spot [Phaeoisariopsis personata (Berk. & Curt) V. Arx.] (LLS) and rust (Puccinia arachidis Speg.) diseases were improved for oleic acid content using marker-assisted backcrossing. Since both the recurrent parents already possessed the mutant allele at AhFAD2A, only mutant allele at AhFAD2B was transferred from the donor 'SunOleic 95R' (oleate of 80.6%). Three rounds of backcrossing with foreground selection using allele-specific polymerase chain reaction (PCR) and Kompetitive allele-specific PCR (KASP) assay identified a large number of plants homozygous for the mutant allele at AhFAD2B in BC n F 2 generations. Evaluation of the advanced generations could identify six and 10 lines with significantly higher oleate than GPBD 4 and G 2-52, respectively. Considering the yield, shelling percentage, oil, and oleate content, the most promising lines HOBC 2 GPS_7 and HOBC 2 G2S_5 were selected with 112 and 142% oleate recovery over GPBD 4 and G 2-52, respectively. Double digest restriction-site-associated DNA sequencing of these superior lines showed background genome recovery of 77.5 and 69.0%, respectively. These advanced breeding lines with high oleate (∼80%), resistance to LLS and rust and high productivity are under further trials for possible release as varieties for commercial cultivation. INTRODUCTIONPeanut (Arachis hypogaea L.) is an oilseed, food and fodder crop cultivated in >100 countries on an area of

Genotyping-by-Sequencing Based Genetic Mapping Identified Major and Consistent Genomic Regions for Productivity and Quality Traits in Peanut

“…The 26.5 cM QTL cluster on Ah19 had only three predicted genes. Furthermore, this region was in the vicinity of FAD2B gene that determines OLE and LIN content and therefore used widely for marker-assisted breeding (Jadhav et al, 2021 ).…”

Whole‐genome sequencing based discovery of candidate genes and diagnostic markers for seed weight in groundnut

“…Diagnostic markers accelerate the process of developing improved varieties through facilitating selection using marker‐assisted early generation selection based on single‐seed chipping and rapid generation advancement (Parmar et al., 2021). Deployment of diagnostic markers, including use of KASP markers, for resistance to nematode, leaf rust, and late leaf spot, in addition to high oleic acid content is now been routinely used for improving foliar disease resistance and oil quality using marker‐assisted selection (Chu et al., 2011; Varshney et al., 2014; Janila et al., 2016; Kolekar et al., 2017; Bera et al., 2018; Bera et al., 2019; Deshmukh et al., 2020; Shasidhar et al., 2020; Jadhav et al., 2021). Realizing the importance, we developed and validated four KASP markers (snpAH00031 and snpAH00033 from 8.9‐Mb region and snpAH00037 and snpAH00038 from 1.64‐Mb region of chromosome B06) for seed weight, targeting potential candidate genes to deploy marker‐assisted selection.…”

Forward Breeding for Efficient Selection

“…Among the molecular breeding lines developed through marker-assisted backcrossing for high oleic acid (Janila et al 2016), two Virginia bunch high oleic varieties namely Girnar 4 (ICGV 15083) and Girnar 5 (ICGV 15090) and two Spanish bunch high oleic varieties namely GG 39 (ICGV 16697) and GG 40 (ICGV 16688) are released for cultivation in India. More recently, two elite varieties, GPBD 4 and G-252, have been improved for oleic acid content using MABC (Jadhav et al 2021). Now, development of groundnut backcross lines has been made more precise and efficient using the available genetic resources for LLS and rust resistance (Pandey et al 2020).…”