Climate change can trigger fall armyworm outbreaks: a developmental response experiment with two Mexican maize landraces
Edison A. Díaz−Álvarez, J. P. Martínez-Zavaleta, E. E. López-Santiz, Erick de la Barrera, John Larsen, Ek del‐Val
Abstract
Maize is one of the most important crops in the world, particularly in Mexico where it was domesticated and is central to traditional cultures. The fall armyworm (Spodoptera frugiperda [J.E. Smith]), is a major pest that can greatly reduce production of this crop. Climate change also threatens maize production, as projections estimate an increase of fall armyworm outbreaks. For these reasons, (1) we assessed the changes in the S. frugiperda life cycle along a temperature gradient ranging from 23 °C to 31 °C, and (2) assessed the development of larvae feeding on two Mexican landraces and the responses of each landrace to herbivory under current and predicted climatic conditions; both assessments were conducted under laboratory conditions. Development was faster and each life cycle stage was shorter at higher temperatures. The effect of herbivory differed between the landraces; herbivory was more harmful for White Ranchero than for Yellow. As warmer and drier conditions are expected during this century, sowing appropriate maize landraces that can cope with herbivores under climate change could mitigate potential economic losses.