The suitability of two New World pyralid stalk borers (Diatraea saccharalis and D. grandiosella) for parasitism by Macrocentrus grandii, an Old World parasitoid of European corn borer, was assessed in laboratory studies. Parasitism rates of 41.5% and 11.5% were observed in European corn borer and sugarcane borer hosts, respectively. Only one of 200 exposures of southwestern corn borer resulted in production of a parasite cocoon mass.
The effect of host frass source on the suitability of the three hosts was evaluated in a companion study. European corn borer frass resulted in the highest rates of parasitism, followed by southwestern corn borer and sugar cane borer. Regardless of frass source, southwestern corn borer consistently had the lowest rates of parasitism.
In studies conducted at the quarantine facility of the Plant Protection Institute in Pretoria, South Africa, M. grandii was evaluated against larvae of Chilo partellus and Eldana saccharalis. Results indicate that C. partellus is a marginally suitable host for M. grandii, but there was no cocoon production on Eldana at all.
Species 1: Hymenoptera Braconidae Macrocentrus grandii
Species 2: Lepidoptera Pyralidae Diatraea saccharalis (sugarcane borer)
Species 3: Lepidoptera Pyralidae Diatraea grandiosella (southwestern corn borer)
Keywords: biogical control, host suitability
The ESA 2001 Annual Meeting - 2001: An Entomological Odyssey of ESA