| Abstract Detail
Plant Protection Young, Paul D. [1], Peters, Rick D. [2], Platt, H.W. (Bud) [2], Hale, Larry R. [1]. Sensitivity to metalaxyl-m of Canadian strains of Phytophthora erythroseptica and the chemical suppression of pink rot in the presence of late blight. TO assess the sensitivity of Canadian Phytophthora erythroseptica populations to metalaxyl-m, samples of potato tubers with pink rot were obtained from Alberta, Manitoba, New Brunswick and Prince Edward Island in 2005.The pathogen was isolated from these tubers and tested for sensitivity to metalaxyl-m at various concentrations using an in vitro agar assay. In total, 48 isolates of P. erythroseptica obtained from 13 individual fields or storages were tested. All isolates from Alberta (7 isolates from two samples), Manitoba (11 isolates from 2 samples), and Prince Edward Island (1 isolate from 1 sample) were sensitive to metalaxyl-m. Most isolates from New Brunswick (23 isolates from 6 samples) were also sensitive to metalaxyl-m. However, 2 samples from New Brunswick yielded isolates (4 and 2 isolates, respectively) that were moderately resistant to metalaxyl-m. Pink rot, caused by metalaxyl-m-sensitve strains of P. erythroseptica, was suppressed in inoculated tubers from plants receiving field applications of metalaxyl-m, including tubers previously inoculated with P. infestans and showing advanced symptoms of late blight. Similarly, growth of P. erythroseptica in vitro was suppressed in liquid substrates amended with 0.5 µg/ml metalaxyl-m, even after these substrates had been utilized as a nutrient source by active cultures of metalaxyl-m-resistant isolates of P. infestans. These studies comprise aspects of the continuing evaluation of the effectiveness of metalaxyl-m for control of pink rot in Canada. (poster, plant protection, PAA Membership 2282)
Log in to add this item to your schedule
Related Links:
Agriculture and Agri-Food Canada, Crops and Livestock Research Centre
University of Prince Edward Island, Dept. of Biology
1 - University of Prince Edward Island, Biology, 550 University Ave, Charlottetown, PE, C1A 4P3, Canada
2 - Agriculture and Agri-Food Canada, 440 University Ave., Charlottetown, PE, C1A 4N6, Canada
Keywords:
pink rot
Phytophthora erythroseptica
Phytophthora infestans
metalaxyl-m
Potato
Solanum tuberosum
Late Blight.
Session: Poster-5
Location: Ballroom CD/Monona Terrace
Date: Tuesday, July 25th, 2006
Time: 8:00 AM
Abstract ID:42 |
