PA treatment reduces the population growth of arthropod herbivores on tomato
The reproduction of three arthropods pests of tomato, the mites T. urticae and A. lycopersici (Vervaet, De Vis, De Clercq & Van Leeuwen 2021) and the insect F. occidentalis , was significantly lower on PA-pretreated tomato plants. As shown in Figure 2 ,T. urticae had 54% fewer living offspring (P < 0.001) on PA-treated plants, A. lycopersici 63% fewer (P = 0.002) andF. occidentalis 40% fewer (P < 0.001). PA similarly induced resistance against F. occidentalis in pepper (Capsicum annuum L. ‘Cayenne Long Slim’), as shown inSupplementary Figure S4. As PA is not acutely toxic to these arthropods (Table 1 ), their reduced reproductive rate is likely caused by PA-IR.