Abstract Detail

Host/Plant Pathogen Interactions and Plant Health Management

Ahmed, Hafiz U. [1], Hwang, Sheau-Fang [2], Zhou, Qixing [1], Turnbull, George D. [1], Strelkov, Stephen. E. [3], Peng, Gary [4].

Effect of crop stage on blackleg (Leptosphaeria maculans) disease severity and yield of canola in Alberta, Canada.

Blackleg of canola (Brassica napus L.), caused by Leptosphaeria maculans (Sowerby) Karst. (anamorph: Phoma lingam (Tode ex. Fr.) Desm.), is a serious disease worldwide causing yield losses of 5-50%. To assess the effect of inoculation and frequency of fungicide application on blackleg severity, stand establishment and seed yield of canola at different growth stages, two field sites were seeded with canola and inoculated with blackleg-infested canola stubble at the cotyledon, 5-leaf, or flowering stages. Stand establishment was lower when the plants were inoculated at the cotyledon or 5-leaf stages. Blackleg severity was greater for inoculated plants compared with the non-inoculated control. Inoculation did not affect plant height, pod production or yield. In a separate trial, Headline (pyraclostrobin) was applied at the seedling stage (S), at the seedling + early flowering stages (SEF), or at the seedling + early flowering + late flowering stages (SEFLF). Plant counts and blackleg severity were lower in all plots where fungicide was applied compared with the control. Inoculation did not affect plant height, pods per plant or seed yield. The absence of an effect of inoculation or fungicide application on plant size or seed production likely resulted from the ability of plants to compensate for infection. These studies suggest that the application of of fungicides at the early growth stages reduces blackleg severity and increases stand establishment of canola. The experiment will be repeatedto confirm the results.

1 - Crop Diversification Centre North, Alberta Agriculture and Rural Development, 17507 Fort Road NW, Edmonton, Alberta, T5Y6H3, Canada
2 - Alberta Agriculture and Rural Development, Research and Innovation, Crop Diversification Centre North, 17507 Fort Road, Edmonton Alberta, AB, T5Y 6H3, Canada
3 - University of Alberta, Department of Agricultural, Food and Nutritional Science, 116 St. and 85 Ave., Edmonton, Alberta, T6G2R3, Canada
4 - Agriculture and Agri-Food Canada, Saskatoon Research Centre, 107 Science Place, Saskatoon, SK, S7N )X2, Canada

Keywords:
Growth Stage
Blackleg
Stage of inoculation
fungicide.

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: PPA001
Abstract ID:787
Candidate for Awards:None