增量螟虫是用来确定树龄的一个。

An increment borer is used to determine the age of a tree.

他需要一种能消灭玉米螟虫的杀虫剂。

He needs a pesticide that will kill corn borers.

研究了宁虫素对水稻螟虫的毒力及防治效果。

Toxicities and control effects of Ningchongsu against rice stem borers were tested.

稻瘟病和螟虫等病虫害严重危害着水稻生产，导致水稻产量下降，稻米品质变劣。

Rice blast and stem borers have done harm to rice production, led to decreased rice yield and inferior grain quality.