Efficacy of sulfuryl fluoride on stored-product insects in a semolina mill trial in Italy

摘要

An experimental fumigation was undertaken in a semolina mill in Italy in July 2001 to validate the activity of sulfuryl fluoride determined from laboratory chamber fumigations. The field trial formed part of a series of fumigations completed in Europe and the United Slates. The nine-floor, 16,250-m~3 mill had a concrete basement, clay brick walls and a concrete slab roof. It contained various types of milling machinery typical of modern mills in Europe. The structure was sealed using rigid polycarbonate sheeting, sprayable foam, polyethylene and tape. Seventeen stored-product insect bioassays were introduced throughout the mill priorto fumigation. Insect species and life stages included in the bioassays were mixed cultures of Sitophilus oryzae, Rhyzopertha dominica, Stegobium paniceum, eggs and pupae of Plodia interpunctella, Ephestia kuehniella, eggs and adults of Tribolium confusum and Tribolium castaneum. Monitoring lines to measure gas concentration were placed in close proximity to each bioassay location together with data loggers for recording temperature. The structure was fumigated for 22h 15min, and a range of concentration X time (Ct) products from 1101 to 1501g/h/m~3 were recorded. Following aeration of the structure, the bioassays were removed and incubated under laboratory conditions at 27 deg C and 70 percent r.h. for mortality assessments. No insect survival was recorded following 30 days of incubation, confirming previously determined efficacy findings from sulfuryl fluoride chamber fumigations.