Mar 30, 2018Florida blueberry growers see blueberry gall midge damage
Brittany H. Lee, president, Florida Blueberry Growers Association (FBGA), has communicated with FBGA membership identifying a threat from blueberry gall midge.
“Gall midge is a pest of blueberries, native to North America. The larvae feed inside the flower buds and destroy them, thus causing low yields. Adults are fragile flies, resembling mosquito-type insects. The legless larvae show colors from yellow to red,” Lee said.
According to a report completed by University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) Extension agent Doug Phillips, producers that have reported gall midge infestation have also reported up to 50 percent fruit loss.
The reports have focused on Emerald, Farthing and Meadowlark varieties. “There could be multiple reasons for flower bud damage and the resulting fruit loss, including hydrogen cyanamide and freeze damage. However, in several cases this year it is believed that this type of damage has been caused by blueberry gall midge,” Phillips said in the report.
Phillips and the FBGA are warning producers to be on high alert for gall midges in their production systems this season.
Oscar Liburd, UF/IFAS professor and program leader of fruit and vegetable entomology, will be releasing a bulletin with current gall midge management methods. Until then, the FBGA is asking producers to fill out this survey so it can inform retailers and consumers how much of the crop can be expected at the end of the season.
“As an industry its important to let marketers, retailers and consumers know how much of our Florida product they can expect so we can maintain market stability and pricing. Growers are reporting losses due to both pollination and gall midge,” Lee said.
“Please see the alert below from Doug Phillips, our new IFAS extension agent on gall midge and how to scout and look for damage,” Lee said.
Report from Doug Phillips:
“Several Florida blueberry growers have recently reported flower bud damage and corresponding fruit loss, in some cases up to 50 percent on certain affected cultivars. These reports have focused primarily on Emerald, Farthing and Meadowlark, although other cultivars may have also been affected to some degree.
There could be multiple reasons for flower bud damage and the resulting fruit loss, including hydrogen cyanamide and freeze damage. However, in several cases this year it is believed that this type of damage has been caused by blueberry gall midge. High populations of blueberry gall midge in blueberry can result in significant flower bud injury and reduce fruit set and yield.
Females lay eggs in floral and vegetative buds just after bud swell. Gall midge larvae then feed on developing leaf and floral buds. Affected floral buds develop a dry, shriveled appearance and will often disintegrate. Damaged leaf buds are characterized by misshapen leaves and blackened and distorted shoot tips. When the terminal bud on a shoot is injured or killed, shoot elongation growth may be inhibited with excessive later branching occurring just below the damage terminal bud.
Weather may impact the density of gall midge populations, with warmer temperatures above 60˚ F resulting in early emergence. Furthermore, re-infestation of previously infested areas is common if management action is not taken when gall midge injury is observed.
Growers should be aware of the possibility of gall midge damage in their fields this season, resulting in floral bud death and lower fruit set. Dr. Oscar Liburd, University of Florida blueberry entomologist, is preparing a bulletin to be released very soon with current gall midge management recommendations to be implemented after this season’s harvest is complete. Until this extension bulletin is ready to be published, growers can view pesticide recommendations for gall midge in The Blueberry News magazine.”