Natural Occurrence Entomopathogenic Fungi: Beauveria Bassiana and Metharizium Anizopliae from the Population of Colorado Potato Beetle, Leptinotarsa Decemlineata (Coleoptera: Chrysomelidae) in Georgia
Nino Matcharashvili* and Medea Burjanadze*
ABSTRACT
The paper demonstrated the Colorado potato beetle (CPB), Leptinotarsa decemlineata (Say) (Coleoptera: hrysomelidae) its natural enemies such as entomopathogenic fungi. Six isolates were obtained from larvae and adults of the population of L. decemlineata, at the different geographical and climatic zone of potato production. Morphological studies show that five isolates belong to the genus of Beauveria and one isolate of Metharhizium. Microscopic observation of colony growth and conidia arrangement showed general and typical characteristics of Beauveria bassiana in five isolates and one isolates Metharizium anizopliae.
Distribution of EPF among the insects, horizontal transmission, is a critical issue for the control of decemlineata. Experimental results show that adults of the L. decemlineata were infected with a fungal disease as a result of movement in the soil and spread naturally among them.
The beetles moved on the surface of the soil, as well as deep into the soil. On the 5th day few beetles appeared infected with mycosis; on the 9th day their number increased and infected beetles achieved around 50%; Finally, on the 14th day all the beetles were infected and their mortality reached 100%.
The identification and investigation of mycosis infection in the population of Colorado potato beetle, which has developed resistance to many insecticides used, is important to reduce economic losses and save the environment from pollution and is an important pathogen that can be used for the control of this insect.
