Location: Plant Genetic Resources Unit (PGRU)
Project Number: 8060-21000-034-003-I
Project Type: Interagency Reimbursable Agreement
Start Date: Aug 30, 2023
End Date: Aug 31, 2027
Objective:
The specific objectives of the project are to: 1) Evaluate diverse hemp germplasm for resistance to four important diseases of hemp including: a) powdery mildew, b) Fusarium head blight, c) Septoria leaf spot, and d) downy mildew, 2) Use molecular markers to genetically map resistance loci to these four diseases, and develop resistant breeding lines that are available through GRIN.
Approach:
Each year, one-hundred diverse, regulatory compliant hemp accessions will be planted as seedlings in greenhouses in Geneva, NY and Lexington, KY. Three replicates of 5-plant plots will be transplanted in a randomized complete block design in the field at each location. The plants will have 2-meter center-row spacing, and there will be one meter between plants in each row. Powdery mildew, Septoria leaf spot, and downy mildew inoculum will be sprayed onto plants in Geneva, NY. Fusarium inoculum will be sprayed onto plants in Lexington, KY. After inoculation, plots will be evaluated every 7 to 10 days for disease severity. Disease evaluation data will be summarized, published, and made available on GRIN.
All evaluated accessions will be genotyped with a robust genotyping platform that has molecular markers spaced evenly across the genome. Genotyping data will be curated and used with the disease evaluation data to perform genome-wide association analysis. Markers that are tightly linked with disease resistance will be used to facilitate marker assisted breeding for resistant hemp germplasm. Hybridizations with resistant plants will be made with hemp accessions that have exceptional agronomic performance. Populations that are developed from these crosses can be used for future disease and agronomic performance screening projects. Selections from these populations with superior agronomic performance and disease resistance will be used to generate pre-breeding lines with seeds available on GRIN.
