Fumigant toxicity of essential oils against Sitophilus zeamais (Motschulsky) (Coleoptera: Curculionidae): a systematic review and meta-analysis

Our aim was to perform a qualitative review and a meta-analysis with 57 scientific articles (108 assays) published from 1 January 2000 to 31 June 2021 dealing with fumigant toxicity of essential oils (EOs) against Sitophilus zeamais. The studies were obtained from four electronic databases: Web of Science, SCOPUS, PubMed, and Google Scholar. The survey comprised 107 plant species belonging to 26 different families. Lethal concentration values (LC₅₀) of EOs were included in a random-effect model, and two subgroups were defined: “until 24 h” and “more than 24 h”. The EOs more frequently evaluated were those belonging to Lamiaceae (20.18%), Asteraceae (17.43%), Apiaceae (9.17%), and Rutaceae (6.42%). The global mean value was 21.37 (CI₉₅ 16.84–27.12), while the summary mean values of the subgroups were 41.45 (CI₉₅ 31.10–55.26) for “until 24 h” and 8.45 (CI₉₅ 5.72–12.48) for “more than 24 h”. Most species belonging to Apiaceae, Lamiaceae, Asteraceae, and Schisandraceae reported the highest insecticidal effects with mean values that ranged from 1.31 to 27.39 for “until 24 h” and from 0.57 to 5.31 for “more than 24 h”. Additionally, the toxicity of the most effective EOs was discussed by addressing their chemical composition and their major pure compounds chemical features.