Abstract

Cercospora leaf spot (CLS) caused by Cercospora beticola is one of the most destructive foliar disease of sugar beets in all sugar beet-growing areas worldwide. In this study, field trials were carried out to determine the effect of CLS at different cultivars and fertilization level. The result showed that level of resistance against C. beticola from 20 variables were differed significantly (P<0.05) and sorted KWS0149>BETA356>Hi0940>KWS6167>KWS8138>KWS4121>Hi0166>DVA02234>BETA807> KWS0142> Ma096> KWS9522> IS0436> BSTO2431> Ma097> BETA464> BETA812> KWS9145> Hi0474> Hi0732. But, Strong and weak of same varieties resistance from three locations apart from 100 km away of this trial series were significantly different. Levels of resistance against C. beticola from optimized fertilization were significant different (P<0.05). Low nitrogen reduced sugar beet resistant against C. beticola. And level of resistance from 20 variables were differed significantly (P<0.05) and were sorted N₂P₁K₁> N₂P₂K₁> N₂P₂K₀ > N₂P₂K₂> N₂P₁K₂> N₁P₂K₁> N₂P₃K₂> N₂P₂K₃ > N₂P₀K₂> N₁P₂K₂> N₃P₂K₂> N₁P₁K₂> N₀P₀K₀> N₀P₂K₂. So, resistance against C. beticola improved after balance fertilizing. It is possible to reduce the pathogen appearance by using varieties resistance and balance fertilizing, which enhanced host resistance to soft rot disease in a way.

Key word: Sugar beet, cercospora leaf spot, varieties, resistance, fertilization level.