Abstract
The infection routes and effect of the entomogenous fungus, Beauveria brongniartii GSES on the yellow spotted longicorn beetle, Psacothea hilaris were investigated using a conidial suspension and nonwoven fabric sheet containing the fungus, in the laboratory and fig tree fields. The conidial suspension was smeared at a density of 7.1×107 conidia/ml on the antennae, ventral abdomen, tarsi and mouth of adult beetles. Irrespective of the treated part, beetles were infected, but, application on the antennae, tarsi and ventral abdomen was more effective (70%-90% mortality) than on the mouth (30% mortality). When adult beetles were allowed to walk for 5 seconds on the fabric sheet containing 108 conidia/cm2, the quantity of conidia on the adult beetle was 107 conidia/beetle. Quantities of 107, 105 and 104 conidia/beetle were detected when beetles walked for 60 seconds on sheets containing 108, 106 and 105 conidia/cm2, respectively. The mortality of adult beetles walking on sheets was 100% and 85% at densities of 107 conidia/cm2 and 106 conidia/cm2, respectively. Walking times of 5 or 60 seconds did not affect mortality. The adult longevities were longer after walking on sheets with 106 conidia/cm2 than on 107 conidia/cm2. Sheets containing the fungus were bound around the trunks of fig trees to control P. hilaris adults in early summer. The conidial concentration on the sheets was 107 conidia/cm2 for 20 days after attachment and approximately 80% of the adult beetles were infected and killed by the fungus. However, the conidial density decreased to 106 conidia/cm2 after 31 days and the adult beetle mortality fell to 60%.
