UVM Theses and Dissertations
Format:
Print
Author:
Lekkas, Panagiotis
Title:
Dept./Program:
Plant and Soil Science
Year:
2008
Degree:
MS
Abstract:
Lygus lineolaris, the tarnished plant bug, (TPB), is a major pest of fruits and vegetables in North America. There are 385 plant species that have been recorded as hosts for this pest. The pest causes serious damage; food quality is reduced and the cost of control is high. Chemical insecticides are used mainly for control and the insect has developed resistance to them. This necessitates development of new methods of control. One area under investigation is the use of entomopathogens. Because the use of bacteria or viruses requires the insect to feed on them, more emphasis has been given to the use of entomopathogenic fungi. These fungi can be easily incorporated into a comprehensive integrated pest management strategy. The use of a wettable powder and horticultural oil as base formulations for Beauveria bassiana and Metarhiziurn anisopliae, for management of 2nd instar and adult TPB in the laboratory and field was investigated. Contact and residual applications were studied to understand the interactions between the insect and the fungus. For 2nd instar TPB there was a significant interaction between fungal isolates, formulation and application method. No strong relationship between these three factors existed for adults. In the field B. bassiana displayed higher efficacy against TPB when formulated in horticultural oil than when unformulated and applied in water. Applications of unformulated spores of M. anisopliae reduced TPB populations equal to that of the chemical insecticide, carbaryl (Sevin).