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.

摘要

玉米是世界上最重要的作物之一，特别是在墨西哥，它被驯化并且是传统文化的核心。秋粘虫（Spodoptera frugiperda [JE Smith]）是一种主要害虫，可大大降低这种作物的产量。气候变化也威胁着玉米生产，因为预测估计秋粘虫爆发会增加。由于这些原因，（1）我们评估了S. frugiperda的变化沿 23 °C 至 31 °C 温度梯度的生命周期，以及 (2) 评估了以两种墨西哥地方品种为食的幼虫的发育以及每种地方品种在当前和预测的气候条件下对食草动物的反应；两项评估都是在实验室条件下进行的。开发速度更快，每个生命周期阶段在更高温度下更短。草食性的影响因地方品种而异。食草动物对 White Ranchero 的危害大于对 Yellow 的危害。由于预计本世纪将出现更温暖和更干燥的条件，因此种植能够在气候变化下应对食草动物的适当玉米地方品种可以减轻潜在的经济损失。