Abstract Detail

Host/Plant Pathogen Interactions and Plant Health Management

Shi, Amy Fang [1], Filotas, Melanie [2], Bakker, Cathy [1], McDonald, Mary Ruth [3].

Pest and diseases of hops in Ontario, Canada, in 2014.

Hops (Humulus lupulus L.) are an essential ingredient that provides bitterness and aroma unique to beer. Various insects and plant pathogens can reduce yield and quality. Because hops are a re-emerging crop in Ontario, baseline data on pest species and dynamics under eastern North American growing conditions is required to support the continued growth of this industry and develop IPM strategies specific to Ontario. From May to August 2014, two commercial hop yards and one replicated hop cultivar trial at the Simcoe Research Station in Ontario, Canada were scouted weekly for insects and diseases. Potato leafhoppers (Empoasca fabae Harris), Japanese beetles (Popillia japonica Newman), and two-spotted spider mites (Tetranychus urticae Koch) were the most common insect pests found. Cultivars Bertwell, Galena, Zeus, Chinook and Centennial showed both significantly lower number of potato leafhoppers and less severity of hopperburn. The least feeding damage by Japanese beetle was observed on the cultivar Chinook. No differences in two-spotted spider mite counts were seen among cultivars. Downy mildew, caused by Pseudoperonospora humuli (Miyabe & Takah.) G.W. Wilson was observed at all sites. Although no cone damage was observed at harvest due to downy mildew, infected basal spikes and shoots were observed during the growing season. In 2014, symptoms of Alternaria cone disorder (Alternaria alternata (Fr.) Keissl.) were observed at the commercial hop yards and on all ten cultivars at the Simcoe Research Station. Cascade and Bertwell showed significantly lower disease severity compared to the other cultivars, whereas Hallertauer showed the highest.

1 - University of Guelph, Department of Plant Agriculture, 1283 Blueline Road, Simcoe, ON, N3Y 4N5, Canada
2 - Ontario Ministry of Agriculture, Food and Rural Affairs, 1283 Blueline Road, Simcoe, ON, N3Y 4N5, Canada
3 - University of Guelph, Department of Plant Agriculture, 50 Stone Road East, Guelph, ON, N1G 2W1, Canada

Keywords:
none specified

Presentation Type: Poster:Posters for Topics
Session: P
Location: Hall D/The Shaw Conference Centre
Date: Monday, July 27th, 2015
Time: 5:30 PM
Number: PPA034
Abstract ID:736
Candidate for Awards:None