中文摘要：

粘虫Mythimna separata是我国玉米、小麦和水稻三大主粮作物上的重大害虫,对我国粮食安全有重大威胁,每年在我国南北往返迁飞危害。近年来,粘虫在我国的发生危害呈现出新的特点,主要体现为：一是受害严重区域发生变化,各世代危害范围扩大;二是主要危害世代发生变化,2代、3代粘虫发生较重;三是主害作物发生变化,玉米成第一大危害作物;四是迁飞规律发生变化,南北往返迁飞格局不变;五是田间种群抗药性明显增强,防治困难程度加重;六是生物学习性发生变异,适应能力增强。针对以上发生危害新特点的形成原因和未来趋势进行了分析与讨论。

英文摘要：

The oriental armyworm, Mythimna separata （Walker） is a key agricultural insect pest that damages important food crops, including maize, wheat and rice, and which consequently poses a major threat to food security in China. Aspects of the ecology of this species have changed in recent years. First, the area most seriously affected by this species has changed and its range has expanded. Second, the main generations causing crop damage have changed; the second and third generations are now the most serious infestations. Third, the extent to which different crops are damaged has changed; maize has become the most seriously damaged host plant. Fourth, although the general pattern of cyclical migration between South and North China remains unchanged, aspects of its migration have changed. Fifth, pesticide resistance has increased making the species more difficult to control. Sixth, aspects of its biology have changed resulting in stronger adaption to the environment. The reasons for these changes are analyzed and discussed.