Location: Emerging Pests and Pathogens Research
Project Number: 8062-22000-023-015-A
Project Type: Cooperative Agreement
Start Date: Sep 1, 2023
End Date: Aug 31, 2024
Wild potato species offer novel resistance to potato cyst nematodes (PCN), pests of quarantine concern worldwide. The goal of this project is to identify wild potato clones for PCN resistance and collect phenotypic data from a Y1-5-derived mapping population for downstream mapping and cloning of novel PCN resistance genes present in wild potato clone Y1-5. The identification of new resistant germplasm and cloning of novel resistance genes would accelerate breeding for PCN resistance in U.S. potato cultivars, thereby providing effective tools for the control or eradication of potato cyst nematodes in the U.S. The specific objectives of the project include: 1) Use pot bioassay to identify Solanum boliviense and S. brevicaule clones for resistance against Ro2 and G. pallida, and 2) Conduct bioassays to determine resistance/susceptibility of the F1 progeny of Y1-5-derived mapping population.
Objective 1: Wild potato clones will be propagated in tissue culture and then transferred to pots. Once plants are established, they will be inoculated with nematode eggs using standard lab protocols. Inoculated plants will grow for three months and nematode cysts will be extracted from the soil after plants are taken down. In the bioassay test, ‘Russet Burbank’ and ‘Desiree’ (susceptible cultivars) as well as ‘Brodie’ (resistant to Ro2) and ‘Innovator’ (resistant to G. pallida) will be included as controls and a final cyst count will be used to determine the level of resistance for each clone. Objective 2: ARS and Cornell University will use pot bioassay to determine nematode resistance/susceptibility of the Y1-5-derived F1 population. In the bioassay test, each progeny clone will have at least 3 replicates and both the resistant (PI 473011) and susceptible (PI 498218) parents will be included as controls. A final cyst count will be obtained for each clone and then compared with those from the resistant and susceptible parents to determine their resistance or susceptibility. The obtained phenotypic data will be used to guide the downstream mapping and cloning of the endogenous R genes expressed in Y1-5.