This forecast provides information on the date when we expect 10% of oilseed rape plants to show symptoms of phoma leaf spot, generally regarded as the threshold when considering the need for a fungicide application targeted against phoma.The forecast uses temperature and rainfall data to simulate the development of the Phoma fungus on crop debris and subsequent infection of young plants. For more information on the biology and the life cycle of the phoma stem canker pathogen, please see the Epidemiology page.
Phoma stem canker - Epidemiology
Phoma stem canker (blackleg), caused by Leptosphaeria maculans, is an important disease on oilseed rape (canola, rapeseed,Brassica napus, Brassica juncea, Brassica rapa) causing seedling death, lodging or early senescence in Australia, Canada and Europe.