Dasineura oxycoccana. [Distribution map].

A new distribution map is provided for Dasineura oxycoccana (Johnson), Diptera: Cecidomyiidae. Hosts: Vaccinium spp. Information is given on the geographical distribution in Africa (Morocco), Asia (Japan, Honshu, Korea Republic), Europe (Croatia, Czech Republic, Germany, Italy, Latvia, Lithuania, Slovenia, Switzerland, UK, England) and North America (Canada, British Columbia, New Brunswick, Nova Scotia, Quebec, Saskatchewan, USA, Florida, Georgia, Maine, Massachusetts, Michigan, Mississippi, New Jersey, Oregon, Washington, Wisconsin).

First report of Dasineura oxycoccana in Lithuania – Short Communication

Damage by the blueberry gall midge Dasineura oxycoccana (Johnson) (Diptera: Cecidomyiidae) was found on different cultivars of highbush Vaccinium corymbosum L. at different localities of Lithuania. D. oxycoccana is a serious insect pest of blueberries in North America. In 1996, unusual damage on blueberries was observed in Europe. This is the first report of the blueberry gall midge occurrence in blueberry plantations in Lithuania.

The Blueberry Gall Midge (Diptera: Cecidomyiidae): A Recent Pest of Wild Blueberry (Vaccinium angustifolium; Ericales: Ericaceae) and Its Impact on Potential Yield

Blueberry gall midge, Dasineura oxycoccana (Johnson) (Diptera: Cecidomyiidae), is an emerging pest on wild blueberry, Vaccinium angustifolium Aiton (Ericales: Ericaceae). The purpose of this study was to document the population increase of blueberry gall midge on this crop in Maine since its discovery in 2003 until 2018. Dasineura oxycoccana appears to have three generations during the prune cycle in Maine wild blueberry, although this may vary among years. Prune fields have higher infestation rates than crop fields, most likely due to the greater abundance of susceptible leaf tissue. Production system does affect infestation rates. Fields managed under a high input system exhibit lower gall midge infestation than low or medium input fields. Field infestation rates in organic fields were intermediate to high input and low and medium input fields. In seven trials conducted between 2010 and 2017, D. oxycoccana infestation of stems resulted in significantly fewer flower-bud clusters developed at the end of the prune year in four of seven trials and significantly fewer viable flowers during bloom in the crop year in four of seven trials. Two of the seven trials resulted in significantly more flowers on infested stems than noninfested stems, evidence that in some years D. oxycoccana infestation may stimulate flower-bud production, resulting in an increase in potential yield. We provide an optimal sampling plan for D. oxycoccana infestation sampling and economic thresholds for three levels of production (yield levels) and three expected prices that growers might receive.

Developing fruit inhibit the regrowth of cranberry shoots after apical meristem injury by larvae of Dasineura oxycoccana (Diptera: Cecidomyiidae)

Larvae of gall making tipworm feed on and injure the apical meristems of cranberry shoots/uprights, disrupting vegetative growth. The majority of tipworm-injured flowering uprights do not resume vegetative growth via activation of lateral axillary buds (side-shoots) before the onset of dormancy. Furthermore, growth and flowering of uprights that fail to produce side-shoots after injury may be inhibited in the following year. In cranberry, limited availability of total nonstructural carbohydrates during fruit development has been reported. Thus, competition between developing fruit and lateral axillary buds for available resources may suppress vegetative regrowth in tipworm-injured flowering uprights. We carried out deblossoming experiments in the field and greenhouse to determine if presence of developing fruit inhibited the growth of side-shoots in tipworm-injured flowering uprights. We also compared tipworm-injured flowering and vegetative uprights to determine if growth form of an upright influenced regrowth after injury. Removal of flowers from tipworm-injured flowering uprights increased the production of side-shoots in three cultivars of cranberry (Ben Lear, Howes, and Stevens). In addition, more tipworm-injured vegetative uprights resumed growth by producing side-shoots, as compared with flowering uprights (Howes and Stevens). Our results suggest that unequal partitioning of resources between developing fruit and lateral axillary buds inhibits regrowth in tipworm-injured flowering uprights of cranberry.