UC Davis

Quarantine insects can be major barriers to international trade if the commodities must bedisinfested according to importer biosecurity regulations. Here we report case studies for the development of phytosanitary approaches to control blueberry maggot (BBM), Rhagoletis mendax (Curran), and brown marmorated stink bug (BMSB), Halyomorpha halys (Stål), in regulated articles, horticultural and non-horticultural respectively. Blueberry maggot, a fruit fly native to Eastern North America, is a major pest of blueberries in this region that can prevent the trade of fresh blueberries across political borders, domestic and abroad. A novel method for quantitatively tracking the development of BBM in blueberries is described with application toward a systemsbased approach for pest control at the probit 9 level, which includes a postharvest methyl bromide fumigation already familiar to industry. BMSB is an agricultural and urban pest that can cause damage to over 300 hosts. Overwintering BMSB, which enter diapause and aggregate in homes, vehicles, and other non-horticultural goods, are a major concern to Australia and New Zealand who demand imported consignments of refugia are fumigated. We report the efficacy of ethyl formate (EF), applied as a 16.7% by mass dilution in carbon dioxide, for controlling BMSB. A difference was identified in the relative tolerance between diapausing and non-diapausing BMSB, whereby non-diapausing BMSB are more tolerant to EF at durations less than 5.9 hours, but less tolerant than diapausing BMSB at longer durations.