Biological control of Diatraea spp. (Lepidoptera: Pyralidae) in sugarcane crops in Central Venezuela.

In 1990-1996, we evaluated the relative importance of the Amazonian fly (Metagonystilum minense) and the wasp (Cotesiaflavipes), in sugarcane crops, in Central Venezuela. We observed a significant decrease in relative abundance of Diatraea spp. when the Amazon fly abundance increased but not with the wasp abundance. Diatraea spp. abundance in presence of both parasitoids was similar to its abundance throughout the last 45 years, when only inundations of M. minense occurred. However a net effect by using both parasitoids was not evident. M. minense is probably the stronger pest control, because its more efficient in its host searching than C. flavipes and is better as competitor than the wasp.