Metarhizium anisopliae 715C were
tested separately against field collected third instar nymphs using a topical spray and via ingestion
with lettuce inoculated with conidia. The highest concentrations of 1.5×108
spores/ml for B. bassiana
and 2×107
spores/ml for M. anisopliae caused 100% and 53.3% mortality respectively when they were
sprayed onto the nymphs. When ingested by insects using lettuce baits inoculated with different
conidial concentrations the cumulative mortality caused by B. bassiana at a concentration of 5×106
conidia/ml was 30%, whereas M. anisopliae at the same concentration caused 43% mortality. Both
species of fungi caused significant mortality of U. zebra by both contact and ingestion.