臺灣目前作物田內及非耕地上均已普遍發現對巴拉刈具抗性之加拿大蓬品系，但在中南部各山區仍舊可以找到不同程度之感性品系。施用3l/ha藥量之巴拉刈於抗感品系之加拿大蓬植株上，發現感性品系內之有效葉面積，葉綠素含量和植株地上部乾重會顯著降低，而抗性品系者則與對照無顯著差異。另外以嘉磷塞防治此抗性草可達完全防治之效果。

paraquat resistant biotypes of Erigeron canadensis were prevalent in Taiwan. Plants of different degrees could be collected from the fields where paraquat has been used commonly. However. more susceptible biotypes of E. canadnsis would be collected on the mountain areas where less application of araquat was suggested. Leaf area, chlorophyll content and plant dry weight of the susceptible biotypes decreased significantly when applied with paraquat at 3L/ha, but those from the resistant biotypes did not differ markedly with controlled plants. Glyphosate could attain total control of paraquat nesistant biotypes of E. canadensis.