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

Abstract

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.

Bottom‐up and top‐down forces in plant‐gall relationships: testing the hypotheses of resource concentration, associational resistance, and host fitness reduction

“…When attacked by bud galling aphids, the host increased the number of branches while fruit production was not affected (Kurzfeld-Zexer et al, 2010). In stem galls induced by Cecidomyiidae, the host reduced the number of flowers in 57% of the crops, but increased the number of flowers during the second flower bloom (Collins & Drummond, 2019).…”

“…Although galling insects attack only a small part of the plant, they can often reduce foliar area (de Silva et al, 2015), cause cytological and metabolic damage to the host plant (Nyeko, 2005;Moens et al, 2009;Oliveira et al, 2016), and change the sink and source relationships between plant tissues (Oliveira et al, 2017;Martini et al, 2020). These metabolic changes can lead to shifts in host architecture and reduce the production of reproductive structures (Leege, 2006;Collins & Drummond, 2019). These findings demonstrate a need to clarify the impact of galling insects on host fitness, which may include the gall system as a driver of ecosystem productivity.…”

Will Climate Warming Alter Biotic Stresses in Wild Lowbush Blueberries?

“…For overall leaf spot disease, the percentage of powdery mildew, Sphaerulina leaf spot, and leaf rust incidences were pooled and treated as a single category of leaf spot [48]. The insect pest observations of incidence were based on the symptoms of infestation on leaves for the blueberry gall midge and the red-striped fireworm [36,49]. The percentage of leaves infested was rated visually on a rank scale.…”

“…The percentage prevalence of Sphaerulina leaf spot, powdery mildew, leaf rust, and Phomopsis twig blight were determined separately based on their symptoms (Figure 2) in a 0.25 m × 0.25 m area within each plot on 21 August in 2019, and 28 August in 2020, respectively. incidence were based on the symptoms of infestation on leaves for the blueberry gall midge and the red-striped fireworm [36,49]. The percentage of leaves infested was rated visually on a rank scale.…”

“…Secondly, the most common native insect pests in Maine wild blueberries fields are blueberry gall midge (Dasineura oxycoccana Johnson), blueberry spanworm (Itame argillacearia Packard), blueberry fea beetle (Altica sylvia Malloch), the blueberry thrips complex (Frankliniella vaccinii Morgan, Catinathrips vaccinophilus Hood, and Catinathrips kainos O'Neill), blueberry maggot fly (Rhagoletes mendax Curran), and grasshoppers of many species (primarily Melanopus spp.). These pests are directly or indirectly related to yield variation [33][34][35][36][37]. Another pest, the red-striped fireworm (Aroga trialbamaculella Cham.)…”