Production of oogonia and Oospores of Leptolegnia chapmanii Seymour (Straminipila: Peronosporomycetes) in Aedes aegypti (L.) larvae at different temperatures

PELIZZA SEBASTIAN ALBERTO; SCORSETTI ANA CLARA; LÓPEZ LASTRA C.C; GARCÍA JUAN JÓSE

MYCOPATHOLOGIA

Springer

Año: 2010 p. 71 - 74

0301-486X

The aquatic Oomycete fungus Leptolegnia chapmanii Seymour is pathogenic to mosquito larvae, but it has been little studied since it was first isolated. Although studies have been performed on different biological isolates of L. chapmanii around the world, they were made on zoospores and very little or even nothing is known about the sexual stage (oogonia and oospores), which allows L. chapmanii to remain in the environment when conditions are not favourable. The main objective of this study was to determine the relationship between temperature and time of onset of L. chapmanii oogonia and oospores in Ae. aegypti larvae. Leptolegnia chapmanii infected IV instar Ae. aegypti larvae were incubated under different temperatures between 5-45º C and photoperiod-controlled during 90 days. The number of oogonia and oospores were daily examined for each tested temperature. As was expected, low temperatures extended times of oogonia formation, as much as seven times. Likewise, temperatures affect significantly the number of oogonia produced.