Plant essential oils: the way forward for aphid control?

Over the past decade or so, there has been an increasing concern that the use of conventional synthetic pesticides may be having a detrimental effect not just on pollinators and other beneficial insects (Goulson et al., 2015; Regan et al., 2017), but also on insects in general (Sorg et al., 2013; Pisa et al., 2015; Leather, 2018; Main et al., 2018). In addition, the problem of insect resistance to insecticides is a serious problem, with almost 600 arthropod species‐resistant to one or more of the chemical groups commonly used in crop protection products (Sparks & Nauen, 2015). Aphids are particularly good at evolving resistance to insecticides, with the peach–potato aphid, Myzus persicae displaying six types of resistance (Simon & Peccoud, 2018). There is obviously a need to develop new crop protection products that are fully compatible with modern Integrated Pest Management approaches. Biopesticides based on entomopathogenic fungi have been used for many decades but their development and use has been hampered by legislation and, in some cases difficulties with formulation and delivery (Chandler et al., 2011).