RESUMO
BACKGROUND: The phorid fly Megaselia halterata Winnertz (Diptera: Phoridae) is the principal vector of Microdispus lambi (Acari: Pygmephoroidea) in Spanish Agaricus bisporus Lange (Imbach) mushroom farms. This myceliophagous mite does not appear to be a pest in Agaricus bitorquis (Quél.) Sacc mushroom crops. This study explores the role of phorid flies as vectors of Microdispus lambi in Agaricus bitorquis mushroom crops. RESULTS: The incidence of M. lambi in A. bitorquis growing substrates did not reach appreciable levels at any point during the growing cycle. The presence of phorid flies in A. bitorquis farms was normally higher than that in the case of Agaricus bisporus Lange (Imbach) species. The percentage of phorid vectors did not statistically differ between both Agaricus crops during infection periods. However, by the end of the crop, this percentage had increased only in A. bisporus crops, coinciding with a high incidence of mites in the substrate of this mushroom species; Megaselia halterata emerging from the mushroom substrate of A. bitorquis summer crops did not carry mites as they were absent from compost and casing. CONCLUSION: M. halterata is a pest in Spanish A. bitorquis mushroom crops, meanwhile M. lambi, its phorectic mite, has shown not to be a pest of this species mushroom farms during the spring-summer growing season. A. bitorquis crops could potentially be used as an IPM measure to decrease the incidence and prevent the propagation of the myceliophagous mite M. lambi in A. bisporus mushroom growing farms. © 2020 Society of Chemical Industry.