title: Factors influencing the infectivity of isolates of Paecilomyces fumosoroseus against diamondback moth, Plutella xylostella.
abstract: Paecilomyces fumosoroseus isolate 1576 was isolated from an insect, but is avirulent against larvae of diamondback moth, Plutella xylostella, and several other species. Isolate 1576 grew faster and produced more conidia than isolate 4461 on potato dextrose agar. Pregermination of conidia failed to increase the infectivity of isolate 1576, but the procedure did increase the infectivity of isolates 3682, 4461, and 4482. Isolates 1576 and 4461 were both more infective when moisture was high during incubation of inoculated larvae. Starved Pl. xylostella larvae were more susceptible than fed larvae to isolate 1576 (40 and 10% mortality, respectively), but starved and fed larvae were similar in susceptibility to isolate 4461. These results show that isolate 1576 grows vigorously in aerial culture and is capable of infecting stressed Pl. xylostella larvae. Further tests are needed to characterize its pathogenicity toward its original host or closely related species.
authors.affiliation: Department of Entomology, Cornell University, Ithaca, New York 14853, USA.
authors.forename: J A
authors.initials: JA
authors.lastname: Altre
authors.forename: J D
authors.initials: JD
authors.lastname: Vandenberg
mesh_terms: D000818:Animals; D004198:Disease Susceptibility; D006813:Humidity; D007814:Larva / Q000502:physiology; D009036:Moths / Q000382:microbiology*; D009181:Mycoses / Q000209:etiology; D010143:Paecilomyces / Q000472:pathogenicity*; D013217:Starvation / Q000503:physiopathology