Efficacy of Beauveria Bassiana for the Management of Economically Important Wireworm Species (Coleoptera: Elateridae) in Organic Farming

Abstract

Wireworms, the larvae of click beetle species Agriotes lineatus, A. obscurus and A. sputator are serious pests for several field crops. They are considered severe pests of potato tubers and the damages caused by them can be resulted a significant loss especially in organic crop production. Since synthetic insecticides are prohibited in Organic Farming; biological control methods have to be used in organic crop production. In the current study naturalis Beauveria bassianaa strain ATCC 74040 was used both under laboratory and field conditions using wheat and potato crops as a food source respectively. Fungus showed a significant mortality in high number of wireworms boxes (50%) compared to low number of wireworms (17%) and untreated boxes (13%) respectively. However, seed germination showed no effect in all three categories. Field data have shown mixed results when B. bassiana has been applied in a variety of application methods. Maximum infestation (3.99%) was recorded in untreated plots; while significantly lower damage (1.11%) was recorded in whole surface treated plots. During first year all the treatments were significantly different from each other; however, no significant differences were noted between furrows and whole surface applications but were different from control treatment during second year of experimentation. The results showed that the biological control of wireworms by using entomopathogenic fungi, such as B. bassiana is a promising target specific option without disturbing the other communities in the soil.