كليدواژه :
ساق سياه , كلزاي پاييزه , LEPTOSPHAERIA MACULANS , blackleg , resistance , Rapeseed , كشاورزي , LEPTOSPHAERIA MACULANS
چكيده لاتين :
Blackleg disease of rapeseed, which is caused by Leptosphaeria maculans (Phoma lingam), is considered as one of the destructive diseases of crucifera family and has resulted in total yield loss in some locations. It appears as an endemic disease in many areas of the world, especially in rapeseed fields. In this study, the response of six winter cultivars of rapeseed to the two isolates of the fungus (Aliabad and Bandar Torkman) was evaluated. Plants were inoculated in different growth stages: cotyledon, and stages, 2.3-2.4, 2.1, and 3.2, using spore suspension under 23±1°C on the basis of established procedures for a successful infection. Inoculated plants were kept under plastic covers for 48 hours in order to provide a 1O0% relative humidity. After inoculation period, disease severity was assessed in cotyledon stage by the method of William and Deiwich, in stage 3.2 by Mc Nabb and Rimmer, and in stage 5 on the basis of Newman and Bailey, and also Mc Nabb and Rimmer. It was revealed that responses of Okapi and SLMO46 to disease were homogenous in all stages. Okapi was recognized more susceptible and SLMO46 more resistant than other cultivars under study. Talaych, Regentx Cobra, Fornax and Ceres which showed different reaction during
different stages of inoculation, indicated the heterogenicity of response to blackleg disease in these cultivars.
