Exotic insectpests can produce both short-and long-term effects on forest ecosystems.
外来害虫可以对森林生态系统产生短期和长期的影响。
2
Scientists have made genetic modifications to cotton to increase its resistance to insectpests.
科学家对棉花进行了基因改造，以增强其对害虫的抵抗力。
3
According to farmers' report, the amount of insecticide needed per acre to control insectpests was only slightly lower for those who tried the modified seed than for those who did not.