Biocontrol of invasive alien weeds has produced great benefits, but concerns over undesirable impacts on non-target plants and/or indirect interactions between biocontrol agents and other biota impede the implementation of biocontrol in some countries. Although great strides have been made, continuing uncertainties predicting the realized host range of candidate agents is probably resulting in some being erroneously rejected due to overestimation of risk. Further refinement of host-range testing protocols is therefore desirable. Indirect interactions are inherently harder to predict, and the risk of both direct and indirect non-target impacts may change over time due to biocontrol agents evolving or expanding their range under climate change. Future research directions to better understand the risk of non-target impacts over time are discussed.

入侵性外来杂草的生物防治产生了巨大的好处，但对非目标植物的不良影响和/或生物防治剂与其他生物群系之间间接相互作用的担忧阻碍了某些国家实施生物防治。尽管已经取得了长足的进步，但是持续的不确定性预测候选代理的实际宿主范围可能会由于风险的高估而导致一些错误地被拒绝。因此，需要进一步完善主机范围测试协议。间接相互作用本来就更难预测，而且由于生物控制剂在气候变化下不断演变或扩大其范围，直接和间接非目标影响的风险可能会随着时间而改变。讨论了未来的研究方向，以更好地了解随时间推移非目标影响的风险。