|Griggs, Michael - CORNELL UNIVERSITY|
|Shelton, Anthony - CORNELL UNIVERSITY|
Submitted to: Society for Invertebrate Pathology Meeting
Publication Type: Abstract Only
Publication Acceptance Date: August 1, 1999
Publication Date: N/A
Technical Abstract: Isolates of the fungus Paecilomyces fumosoroseus vary greatly in their infectivity to larvae of the diamondback moth, Plutella xylostella. We observed infection by our least virulent isolate (1576) among stressed insects and wished to determine the conditions under which this isolate might be more infectious. Average larval mortality was significantly higher for isolate 4461 (81%) than isolate 1576 (14%). For both isolates, percentage mortality was significantly greater in high humidity than in low humidity. For isolate 1576, the average percentage mortality of starved larvae (38%) was significantly greater than that of fed larvae (1%). In contrast, starvation did not affect mortality of larvae treated with isolate 4461. Studies are underway to characterize conditions on the cuticle or within the hemocoel of starved larvae that may allow infection by an otherwise avirulent isolate.