SUSCEPTIBILITY OF HIGHBUSH BLUEBERRY CULTIVARS TO LARVAL INFESTATION BY RHAGOLETIS-MENDAX (DIPTERA, TEPHRITIDAE)

Eighteen highbush blueberry, Vaccinium corymbosum L., cultivars were e valuated for larval infestation by the blueberry maggot fly, Rhagoleti s mendax Curran. Most cultivars were evaluated during 3 field seasons. Significantly fewer maggots were found in berries of early-ripening c ultivars, 'Earliblue' and 'Bluetta', than in later maturing cultivars such as 'Bluehaven', 'Coville', 'Darrow', 'Elizabeth', and 'Lateblue'. The oviposition period of R, mendax is synchronized with the ripening dates of mid-season cultivars (late July to early August) in Rhode Is land. This results in more oviposition and higher larval infestations in mid- and late-season susceptible cultivars. Among the mid- to late- season cultivars, 'Northland' and 'Herbert' berries had consistently f ewer maggots than other cultivars. These cultivars, along with Bluetta and Earliblue appear to be good candidates for inclusion into integra ted pest management programs.