Indicating an optimal time of Oulema spp. chemical control on cereals

Abstract

Cereal leaf beetles commonly occurring in numerous countries are pests of economic significance to cereal crops. In Poland two species that are morphologically different Oulema melanopus and Oulema gallaeciana from the Chrysomelidae family have been recorded. Every year beetles and larvae of Oulema spp. significantly damage leaf tissues of cereal leaves, which causes high losses in yields. Extended duration of egg laying and larval development are the main reasons making determination of optimum timing of leaf beetles chemical control very difficult. For determining the accurate time of leaf beetles control, five years’ experiment in a growth chamber and three years under field conditions were performed. Two species of Oulema spp. were reared in order to evaluate impact of temperature and air humidity on the length of egg incubation. On the basis of the obtained results and statistical analysis a mathematical model in the form of multiple regression equation was created. The model supports determining optimal time of chemical control against cereal leaf beetles.