مدیریت بیماری ساق سیاه کلزا ‏Leptosphaeria maculans‏ ‏

Blackleg, caused by Leptosphaeria maculans is one of the major diseases of canola (Brassica ‎‎napus L.) globally and in Iran (particularly in northern regions as Mazandaran and Golestan ‎‎provinces). Management of the disease is dependent on the regional conditions. The various ‎‎types of disease management include adequate crop rotation intervals with cereals, removal of ‎‎residual debris, pillowing management, changing planting date, choosing the best plant density, ‎‎fertilizer treatments, biological control methods and use of fungicides as triazoles. ‎Fundamentally, our ‎strategies against of this fungus may be varied in using one or a ‎combination of these methods. ‎However controlling this disease in the humid conditions, which ‎are favourable conditions for ‎fungus, is particularly challenging as well as northern part of Iran. ‎At the present time, the best way for management of canola ‎blackleg is the deployment of ‎quantitative and qualitative resistance genes in commercial hybrids ‎and varieties against L. ‎maculans to prevent the disease development. In our country, new ‎hybrids and varieties have ‎been imported without any assessment of their susceptibility or ‎resistance to existing races of L. ‎maculans. Given the importance of using resistant hybrids to ‎reduce the cost of managing this ‎disease, as well as import restrictions of resistant hybrids to ‎Iran, there is a need for domestic ‎hybrid production and knowledge of the endemic races in our ‎country. Furthermore, given there ‎has not been done any test to identify of infection of ‎imported canola hybrids to Plenodomus ‎lingam (Teleomorph: L.maculans), it would be ‎problematic through developing the new ‎pathogenicity groups in the near future.‎