Oviposition and Survivorship of Sugarcane Grubs (Coleoptera: Scarabaeidae) at Different Soil Moistures

Abstract

The oviposition of the sugarcane grubs. Cyclocephala parallela Casey and Ligyrus subtropicus (Blatchley), was measured at different soil moistures. In addition, the flood tolerance of third instars of these two species was also measured. Oviposition of both species was defined by Gaussian models that showed oviposition rates approaching zero at soil moisture extremes and the optima at the midrange of soil moistures. However, our data showed that C. parallela oviposited in wetter soils than L. subtropicus. This ovipositional behavior corresponds to the greater flood tolerance of third instar C. parallela compared with L. subtropicus.