Disease and canopy control in oilseed rape using triazole fungicides

摘要

Light leaf spot (Pyrenopeziza brassicae) and Phoma (Leptosphaeria maculans) are major diseases of oilseed rape and each can cause yield losses greater than 1 t ha~(-1). Control of these diseases can be achieved using the triazole fungicides flusilazole and tebuconazole. Tebuconazole also has plant growth regulating activity, reducing crop height and lodging if applied at stem elongation. The plant growth regulating (PGR) effect can also increase yield. Spraying of larger crops may result in a better canopy structure and increased yield, whereas spraying smaller crops may result in an over-regulated canopy and loss of yield and pod quality. The aim of this investigation is to look at the rungicidal and plant growth regulating activity in relation to timing of application and crop status, whilst maintaining optimum disease control and yield. Different sowing dates and seed rates will result in different canopy sizes and structures and therefore the different responses to chemicals applied can be monitored, This poster will describe the results of first year trials.