Characterization of the Fungal Pathogen, Entomophaga aulicae (Zygomycetes: Entomophthorales) in Larval Populations of the Green Cloverworm, Plathypena scabra (Lepidoptera: Noctuidae)

Entomophaga aulicae was monitored in populations of noctuid lepidopteran pests of soybean during the 2000, 2001, and 2002 growing seasons in South Carolina and infected only Plathypena scabra larvae. No infection by E. aulicae was detected in 2002. Average infection levels of E. aulicae in P. scabra populations in Blackville were 6.0% and 20.0% in 2000 and 2001, respectively. At Clemson, infection was 15.0% and 23.3% for the two sampling weeks in 2000, and infection reached a high of 50.0% in 2001. Pyriform, multinucleate conidia and spherical to slightly oval resting spores were the primary features of this fungus. When conidia were kept in a high humidity for 6-12 hrs they either formed long germ tubes or secondary conidia. Resting spores were formed by budding from parental cells. This study is the first detailed characterization of E. aulicae from P. scabra.

Characterization of the Fungal Pathogen, Entomophaga aulicae (Zygomycetes: Entomophthorales) in Larval Populations of the Green Cloverworm, Plathypena scabra (Lepidoptera: Noctuidae)

Entomophaga aulicae was monitored in populations of noctuid lepidopteran pests of soybean during the 2000, 2001, and 2002 growing seasons in South Carolina and infected only Plathypena scabra larvae. No infection by E. aulicae was detected in 2002. Average infection levels of E. aulicae in P. scabra populations in Blackville were 6.0% and 20.0% in 2000 and 2001, respectively. At Clemson, infection was 15.0% and 23.3% for the two sampling weeks in 2000, and infection reached a high of 50.0% in 2001. Pyriform, multinucleate conidia and spherical to slightly oval resting spores were the primary features of this fungus. When conidia were kept in a high humidity for 6-12 hrs they either formed long germ tubes or secondary conidia. Resting spores were formed by budding from parental cells. This study is the first detailed characterization of E. aulicae from P. scabra.

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