Our program was initiated in the fall 2001 with a blueberry grower pest survey, which was sent out to the various counties throughout the state of Florida. The purpose of the survey was two-fold: 1) to determine the major insect pest problems affecting blueberry growers in Florida and 2) to determine how we should allocate our research and extension efforts throughout the state. Approximately 50% of the surveys that were sent out were returned. Blueberry growers indicated that the major pest problems were blueberry flower thrips, blueberry gall midge, blueberry bud mite, cranberry fruitworm and blueberry maggot. Flower thrips and gall midge were identified as the two most important insect pests in blueberries. The survey was followed-up with several on-farm visits to blueberry growers throughout the state. Because flower thrips and gall midge were identified as the two most important insect pests in blueberries, most of our research efforts over the last six months were directed against these two insect pests.

Flower Thrips. Our goals were 1) to identify thrips species that were abundant in Florida blueberries and 2) to initiate sampling protocols for detecting thrips within blueberry plantings. A third objective was to investigate reduced-risk insecticides that can potentially be used for controlling flower thrips. Our lab worked closely with Dr. Joseph Funderburk from the North Florida Research and Education Center and Dr. Kenna MacKenzie from Agriculture Canada to identify thrips species affecting Florida blueberries. Dr. MacKenzie also played an integral role in helping to develop sampling protocols for thrips. Our preliminary results have indicated that the Florida flower thrips, Frankliniella bispinosa (Morgan) is the main species that occurs in the north-central region (Highlands County to Columbia County). The data also indicated that thrips density peaks during the flowering periods for southern highbush and Rabbiteye cultivars. Thrips have sucking/rasping mouth parts and are believed to interfere with flower bud development and potentially reduce fruit-set. Thrips may also damage fruit by scarring, which is particularly problematic for a high value crop such as southern highbush blueberry. In our reduced-risk insecticide trials the data indicate that SpinTor at 6 oz per acre significantly reduced thrips population. However, thrips tend to move back into the planting after 72 hours (3 days) post application. The removal of thrips host from surrounding blueberry plantings or using additional management tools such as biological control with minute pirate bugs, Orius spp. may help in reducing thrips population. Further research will be required to confirm this hypothesis. Our work on developing sampling protocols involved investigating simple techniques that included the use of sticky colored boards as well as destructive sampling of blueberry shoots. Preliminary results have indicated that blue and white sticky boards are highly attractive to thrips. However, counting thrips on sticky boards could be very difficult when populations are high.

Gall Midge. Our work on gall midge paralleled our thrips research. Our initial goal was to study blueberry gall midge phenology and develop sampling protocols for detecting midges in blueberry plantings. Secondly, we wanted to quantify blueberry gall midge damage within rabbiteye and southern highbush plantings and to identify potential reduced-risk insecticides for control of blueberry gall midge. Our gall midge research started by investigating suspected cecidomyiid species believed to be feeding on young blueberry shoots. After much taxonomic research, we were able to effectively rear blueberry gall midge Dasineura oxycoccana (Johnson) from infested Rabbiteye blueberry shoots in the laboratory. We were also able to rear all stages of the blueberry gall midge life cycle in the laboratory using samples taken from various plantings. Although anecdotal evidence has previously suggested that midges favor flower buds as opposed to leaf buds, we are attempting to confirm this observation using results from our field experiments. With respect to reduced-risk insecticides, the results indicated that Provado 1.6 F may reduce blueberry gall midge densities. Provado 1.6 F is currently not registered for blueberries, although there is potential for it to be registered in the future if data continue to support its efficacy in suppressing blueberry pests. Field data on gall midge phenology continues to be collected from blueberry plantings on a weekly basis.

Other Pests. Several occasional pests, including leaf-footed bug, stink bug and fall webworm have been found at several plantings throughout Florida. These pests vary in numbers and may be dependent upon growers’ management practices. We will continue to monitor for these pests in upcoming years. If any of these occasional pests change status to "key pest," we will redirect our attention to develop additional management practices for their control.

Research Grants. Our project recently received national funding from USDA Pest Management Alternatives.