CEPAVE   05420
CENTRO DE ESTUDIOS PARASITOLOGICOS Y DE VECTORES
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
First report of resting spores of Pandora neoaphidis (Entomophthoromycotina: Entomophthorales) an entomopathogenic fungus of aphids (Hemiptera: Aphididae)
Autor/es:
SCORSETTI, A.C.; CABELLO, M.N.; LÓPEZ LASTRA, C.C.; JENSEN, A.B.
Lugar:
Córdoba, Argentina
Reunión:
Congreso; VI Congreso Argentino de Microbiología General; 2009
Institución organizadora:
SAMIGE Sociedad Argentina de Microbiología General
Resumen:
The entomopathogenic fungus Pandora neoaphidis (Remaudière et Hennebert) Humber (Entomophthoromycotina: Entomophthorales), has long been investigated as a potential biological control agent of temperate zone pest aphids (Hemiptera: Aphididae). It is aphid-specific, causing natural epizootics in aphid populations, and interacts favourably with aphid predators and parasitoids. There are several hypotheses in the literature about winter survival of P. neoaphidis. One would be that the fungus survives by a continuing infection of anholocyclic populations of aphids. This fact is supported because this fungus is capable of infecting aphids at temperatures up to 5°C. There is evidence that the fungus P. neoaphidis has the capacity to survive for long periods outside the host, in soil as conidia, or hyphal bodies. However, it is known that P. neoaphidis could survive inside host for long periods, under conditions of low temperatures and low humidity. The objective of this study was to investigate the presence of resting spores of P. neoaphidis in aphid at field conditions. Aphids infected by P. neoaphidis were incubated for different time periods and examined by TEM. If resting spores were detected, we preserved cadavers in 70% alcohol. We confirm the presence of P. neoaphidis resting spores with PCR using fungal universal primers. In order to compare the taxonomic position of the resting spores we blasted the sequences in Genbank and have sequenced few additional Entomophthoralean species. The size of the ITS varied among the different species included with a range of approximate, 1000 to 1500 bp. Amplicons of the resting spores from infected aphids had a length of 1080 bp, as did all the tested P. neoaphidis isolates. We were successful in getting sequences from the resting spores of fungal infected aphids. In the present study, the occurrence of resting spores of P. neoaphidis at field conditions is reported for first time.