A study published in Journal of Pest Science examined salicylic acid (SA)- and jasmonic acid (JA)-mediated defences in oilseed rape (Brassica napus) against three aphid species: Brevicoryne brassicae, Lipaphis erysimi and Myzus persicae. Researchers compared hormonal treatments alone and combined with natural enemies, the parasitoid Diaeretiella rapae and the predator Coccinella septempunctata. Hormonal treatments alone produced only moderate aphid reduction, while combining methyl jasmonate (MeJA) with natural enemies gave the most consistent suppression.