Combined effect of an antifeedant α‐amylase inhibitor and a predator Cheyletus malaccensis in controlling the stored‐product mite Acarus siro

Acarus siro is the most abundant and frequent mite to infest stored‐food products, causing allergies and transmitting mycotoxin producing fungi. The predatory mite Cheyletus malaccensis is a candidate species in the biocontrol programme for this pest. In vitro , the α‐amylase inhibitor acarbose is effective against the α‐amylase of A. siro but not against that of C. malaccensis . In vivo , the impact of acarbose on a population of A. siro is investigated along with the interaction with the predator. Various densities of adult parthenogenetic females of C. malaccensis are reared on A. siro feeding on either a control diet or a diet containing different acarbose concentrations. The combined action of both factors significantly improved the final biocontrol efficiency with C. malaccensis , compensating for the lower energetic content of the prey on acarbose by increasing the number of prey caught. Acarbose had no negative effects on the longevity and the length of oviposition period of C. malaccensis but partially reduced its fecundity. The results are discussed in the context of the integrated control of stored‐product mite pests.