Location: Crop Genetics and Breeding Research
Project Number: 6048-21000-031-000-D
Project Type: In-House Appropriated
Start Date: Mar 6, 2023
End Date: Mar 5, 2028
Objective:
Objective 1. Identify and characterize genes/Quantitative Trait Locus (QTLs) controlling resistance to major diseases (leaf spot, white mold, tomato spotted wilt virus (TSWV), and nematodes), preharvest aflatoxin contamination (PAC) and drought stress, and use the information in marker-assisted breeding to develop improved peanut cultivars or germplasm with tolerance to biotic and abiotic stresses.
Sub objective 1.A. Conduct phenotypic evaluations of recombinant inbred line (RIL) populations to aid in the identification and characterization of genes/QTLs controlling resistance/tolerance to biotic and abiotic stresses.
Sub objective 1.B. Develop improved peanut cultivars or germplasm with resistance to leaf spot and/or nematodes.
Sub objective 1.C. Develop peanut germplasm with improved drought tolerance and reduced preharvest aflatoxin contamination (PAC).
Approach:
1.A. Structured recombinant inbred line populations were developed that should be segregating for resistance to leaf spot or drought tolerance or reduced aflatoxin contamination. In-depth phenotyping and genotyping of these populations will be conducted to identify genetic markers for these traits that can be used in peanut cultivar development.
1.B. Breeding populations will be developed by hybridizing cultivars with high yield with breeding lines with resistance to the peanut root-knot nematode and/or resistance to leaf spot. Marker assisted selection will be utilized to select progeny that are homozygous for the desired characteristics (nematode resistance, and/or leaf spot resistance). Selections will then be evaluated in the field for resistance to tomato spotted wilt virus, yield, grade, and other agronomic characteristics.
1.C. Breeding populations will be developed by hybridizing high-yielding cultivars with sources of resistance to preharvest aflatoxin contamination and sources of resistance to drought. These populations will be evaluated under field conditions with drought and heat stress imposed by covering the entire test area with a mobile greenhouse. Aflatoxin contamination of the subsequent yield will be determined using the immunoaffinity column fluorometer method. Progeny will be selected based on relatively low aflatoxin and/or relatively high pod yields.
