Research:2026-03-30/Journal article/evaluation-of-downy-mildew-resistance-in-the-usda-hemp-germplasm-repository-using-high-throughput-and-traditio

ResearchJournal article30 March 2026

Evaluation of Downy Mildew Resistance in the USDA Hemp Germplasm Repository Using High-Throughput and Traditional Phenotyping Methods

Taylere Q. Herrmann, Kerik Cox, Tyler Gordon, Zachary Stansell, Lance Cadle-Davidson, Anna Underhill, Arlyn Ackerman, Craig T. Beil, Moira J. Sheehan, Christine D. Smart

Plant Disease

Screens 108 hemp entries from the USDA Hemp Germplasm Repository for resistance to downy mildew, caused by Pseudoperonospora cannabina and first identified in New York in 2020. Three methods were compared: robotic imaging with convolutional neural network analysis of leaf discs, visual rating of the same discs and detached-leaf assays. Severity ranged from 0 to 100%, and two entries, G 33532 and the cultivar Santhica 27, showed none under all three methods. The authors find the imaging approach promising but in need of refinement, since it underestimated severity against visual scoring. The paper names resistant material held in a public germplasm collection.

Read the paper

DOI10.1094/pdis-09-25-1916-re

Record created 15 October 2026maintained by landrace.wiki editorspage history

2026-03-30 2026-10-15 Evaluation of Downy Mildew Resistance in the USDA Hemp Germplasm Repository Using High-Throughput and Traditional Phenotyping Methods Journal article Botany Taylere Q. Herrmann, Kerik Cox, Tyler Gordon, Zachary Stansell, Lance Cadle-Davidson, Anna Underhill, Arlyn Ackerman, Craig T. Beil, Moira J. Sheehan, Christine D. Smart Plant Disease 2026 10.1094/pdis-09-25-1916-re https://doi.org/10.1094/pdis-09-25-1916-re Screens 108 hemp entries from the USDA Hemp Germplasm Repository for resistance to downy mildew, caused by Pseudoperonospora cannabina and first identified in New York in 2020. Three methods were compared: robotic imaging with convolutional neural network analysis of leaf discs, visual rating of the same discs and detached-leaf assays. Severity ranged from 0 to 100%, and two entries, G 33532 and the cultivar Santhica 27, showed none under all three methods. The authors find the imaging approach promising but in need of refinement, since it underestimated severity against visual scoring. The paper names resistant material held in a public germplasm collection.