Corn borers (Lepidoptera : Noctuidae; Crambidae) in Northwestern Spain: Population dynamics and distribution

Abstract

Corn borers are an important maize (Zea mays L.) pest in northwestern Spain. In order to use meth- ods of control or to breed plant material against corn bor- ers it is necessary to know the life cycle and behavior of this pest. The objectives of this work were to complete the study of the incidence of corn borers in northwestern Spain, to study the behavior of the two species of corn borers inside the plant, and to relate the abundance of borers with climatic factors. To monitor the incidence of the corn borers, data were taken in four localities of the northwest of Spain, during seven years (1997-2003). Sesamia nonagrioides is the most important pest in the coast. Ostrinia nubilalis is as important as S. nonagrioides in the inlands. There were two generations of both borers but a third generation can occur. Damage could hardly be predicted from studying the abundance of adults. S. nona- grioides and O. nubilalis had the same distribution inside the plant and it seems that both species can coexist.