Thrips (Thysanoptera: Thripidae) communities in agroecosystems are poorly known, particularly in Québec, Canada, where thrips can cause damage in strawberry crops. The phenology of anthophagous thrips and their use of cultivated and wildflower resources were monitored in strawberry agroecosystems, encompassing strawberry (Rosaceae) fields and adjacent uncultivated margins, on Orléans Island, Québec, Canada. A community comprised of 11 thrips species was described, dominated during the whole season by pest species Frankliniella tritici and F. intonsa, which is a first mention in Eastern Canada. Surprisingly, the major strawberry pest F. occidentalis was absent in our samples. Thrips species richness and abundance on wildflowers varied, with few flowering plant species supporting a majority of the community. Sampling sites and local wildflower presence influenced the thrips species assemblage observed on strawberry crops. Such a high thrips diversity was unexpected in this agroecosystem. The identified associations between pest thrips and wildflower species will be useful to develop better control programmes in strawberry crops.

Narrow-spectrum insecticides are currently used to control populations of spruce budworm, Choristoneura fumiferana Clemens (Lepidoptera: Tortricidae), in eastern Canada. However, these could have nontarget impacts on other caterpillars – some of which may serve as alternative or alternate hosts to key parasitoids – that are also susceptible to control tactics. This study was conducted to determine how the insecticides, Bacillus thuringiensis variety kurstaki (Btk) and tebufenozide, used to control spruce budworm populations, impact caterpillar communities and associated parasitism rates. Post-treatment field sampling of caterpillars was conducted in 2018 and 2019 in New Brunswick, Canada, at sites treated with either Btk or tebufenozide and at control sites. Caterpillar species richness and abundance, community structure, and parasitism rates were assessed using molecular analyses for 659 collected caterpillars. We found that insecticide applications had no significant impact on abundance, species richness, or parasitism rate relative to the measurements made in the control sites. Nonetheless, a significantly higher caterpillar abundance and lower parasitism rate occurred in Btk-treated sites than in tebufenozide-treated sites. Overall, however, Btk and tebufenozide treatments did not negatively affect the non-budworm caterpillar community under the present conditions of low caterpillar densities, suggesting that parasitoids have alternative and alternate hosts after treatments that target the spruce budworm.

Understanding movements of Drosophila suzukii (Diptera: Drosophilidae) into berry fruit crops from wild-fruit hosts in borders of semi-natural agroecosystems, such as lowbush blueberry, is important to determining harvesting time and managing wild-fruit diversity near crops. This study aimed to inventory the wild-fruit hosts associated with lowbush blueberry (Ericaceae) production in Québec, Canada, near the limits of lowbush blueberry’s eastern North American range. We also tested the hypothesis that fruit traits of berry fruit species present in or near lowbush blueberry fields might explain field infestation levels. Flies of both sexes emerged from five wild-fruit species in 2016, to which six more species were added in 2017. The most productive wild-fruit hosts were Cornus canadensis (Cornaceae) and Aralia hispida (Araliaceae) (> 100 emerged flies/100 g of fruit) in 2016, to which Prunus pensylvanica (Rosaceae) and Rubus idaeus (Rosaceae) were added in 2017. Among nine variables considered in statistical modelling (fruit size, sugar content, and reflected colour bands) and taxonomic family (a nominal variable), none could explain field infestation levels over two years. In lab tests comparing fruits of Cornus canadensis, a common weed within fields, and lowbush blueberries, mated D. suzukii females laid twice as many eggs on blueberries, but both species were equally suitable for development.

The foxglove aphid, Aulacorthum solani (Kaltenbach) (Hemiptera: Aphididae), and the melon aphid, Aphis gossypii Glover (Hemiptera: Aphididae), are among the serious insect pests found in greenhouses. The efficacy of microbial control against these insects has been demonstrated and can be enhanced by the combination of different microbial agents. This study evaluated the efficacy of Bacillus pumilus Meyer and Gottheil PTB180 and Bacillus subtilis (Ehrenberg) Cohn PTB185, used alone and together, to control these two aphids both in the laboratory and in greenhouse on tomato, Solanum lycopersicum Linnaeus (Solanaceae), and cucumber, Cucumis sativus Linnaeus (Cucurbitaceae), plants. The results from the laboratory tests showed an increase in mortality induced by all biological treatments. In the greenhouse, all treatments induced mortality rates significantly higher than that of the control for A. solani. Similarly, all treatments performed better than the control against A. gossypii, significantly reducing its reproduction. Furthermore, we found no additive effects when mixing products nor negative interactions affecting survival for the bacteria investigated. These microorganisms therefore have potential for use in biological control.

Field-acclimated Drosophila suzukii (Diptera: Drosophilidae) from the Saguenay–Lac-Saint-Jean region, Québec, Canada, were examined over two years for winter survival, under the hypothesis that flies select protected overwintering microhabitats. In 2016–2017, flies trapped alive in the field or emerged from infested fruits were submitted to four winter regimes of either constant or daily fluctuating temperatures of 5 °C (2–8 °C) or 10 °C (7–13 °C). In 2017–2018, two fluctuating regimes averaging either 1 °C (–2 to 4 °C) or 3 °C (0–6 °C) were tested. Survival was modelled using Cox proportional hazard models testing probability that mortality risk varies with cold winter regime, fly sex, and fly provenance. Hazard ratios were about 1.7 times higher for males than for females. Models indicate that flies in constant and fluctuating 10 °C, in constant 5 °C, or in fluctuating 1 °C with daily exposure to –2 °C would not survive a six-month winter. Female survival extended to the next summer in fluctuating regimes averaging 5 °C or 3 °C. Estimates of 0.95 quantile survival (5%) indicate that overwintering D. suzukii experiencing such cold temperature regimes during winter, with no prolonged sub-zero temperatures, could survive until July of the following year, which is likely at the high population densities observed.

Exclusion netting systems are effective in various contexts and are increasingly used to control crop pests. However, factors affecting pollination management under nets are poorly known. The pollination effectiveness of commercial bumble bee hives of Bombus impatiens Cresson (Hymenoptera: Apidae) was studied for apple production under exclusion netting systems in a research orchard located in Quebec, Canada during 2016–2017. Sixteen single-row plots of apple trees (plot length: 18.5 m, cultivar GingerGold) were subjected to one of the following four treatments during bloom: (1) introduction of a bumble bee hive placed at the end of the row, under nets; (2) introduction of a bumble bee hive placed in the middle of the row, under nets; (3) negative control with no pollinators, under nets and (4) agronomic control with nearby bee hives (<50 m), without nets. Resulting post-harvest fruit quality (e.g., fruit weight, size, number and distribution of seeds) was evaluated, as well as correlations between bumble bee visitation rates and fruit quality parameters were evaluated. Results suggest that bumble bees provided adequate pollination under exclusion netting systems and that resulting fruit quality was equivalent to that of apple fruit conventionally pollinated by honey bees and wild bees community (bumble bees and other bees) in the orchard environment. Positioning bumble bee hives in the middle of the row provided better fruit load homogeneity in pollinated trees. Additional discussion on bumble bees as apple pollinators and on pollen distribution methods is also included.

The growth of the commercial pollination industry raises important concerns regarding honey bee (Apis mellifera Linnaeus; Hymenoptera: Apidae) health and development. While providing such services, honey bees are often exposed to undiversified pollen sources that may contribute to nutritional deficiencies, notably in protein and amino acids. To understand how honey bees are affected during provision of pollination services, we compared honey bee colonies that pollinated lowbush blueberry (Vaccinium angustifolium Aiton; Ericaceae) and/or cranberry (Vaccinium macrocarpon Aiton; Ericaceae) crops (management strategies) with control colonies in a diversified farmland environment. We identified the floral species of pollen collected by honey bee colonies in those crops compared to pollen collected by control colonies. We also analysed the protein and essential amino acid content of collected pollen and bee bread and measured the nutritional impact of pollination services on honey bee colonies. We found that honey bees providing blueberry and/or cranberry pollination services are exposed to a less diversified pollen diet than colonies located in a farmland environment, especially in a cranberry field. There was a significantly lower proportion of crude protein content in collected and stored pollen during provision of blueberry pollination services, which led to a smaller brood population. Many nutritional deficiencies were measured with regards to essential amino acids.

Drosophila suzukii (Matsumura) (Diptera: Drosophilidae), the spotted-wing drosophila, is an invasive pest of fruit crops, which appeared in eastern Canada in 2010. It represents a major threat to lowbush blueberry (Vaccinium angustifolium Aiton; Ericaceae) in the Saguenay-Lac-Saint-Jean region, Québec, Canada, at the northern limits of its distribution. The dynamics, overwintering capacity, population fluctuations, and damage to lowbush blueberry of D. suzukii are unknown in Saguenay-Lac-Saint-Jean. We aimed to 1) document D. suzukii abundance and phenology in lowbush blueberry in separate localities; 2) evaluate the potential of D. suzukii to overwinter and examine population dynamics over three seasons; and 3) study the spatial distribution of D. suzukii in lowbush blueberry fields with respect to forested borders. Drosophila suzukii is abundant in lowbush blueberry fields of Saguenay-Lac-Saint-Jean. In spring, D. suzukii were absent until late June, when few summer-morph females appeared. Drosophila suzukii densities started to increase regularly in August, with increasing male proportions, to culminate in fall at high levels with balanced sex ratios. Overwintering remains uncertain, D. suzukii being undetectable in spring despite intensive trapping. Appearance of diapausing winter morphs at high densities indicates that D. suzukii responds appropriately to local conditions preceding cold winter. Models of variation of D. suzukii densities and lowbush blueberry fruit infestation with distance from borders indicate that forest borders are favoured habitats over lowbush blueberry fields and the source of D. suzukii moving to some extent into lowbush blueberry fields.

The cyclamen mite (Phytonemus pallidus Banks; Acari: Tarsonemidae) has recently become a more important pest in Canadian strawberry (Fragaria × ananassa Duchesne ex Rozier; Rosaceae) production with the withdrawal of the pesticide endosulfan in 2016, yet its phenology under field conditions in Canada is poorly known. Moreover, while its biological control with predatory mites has shown potential, the effectiveness of this method has never been investigated under eastern Canadian field conditions. The objectives of this study were to (1) monitor populations of P. pallidus in strawberries for two consecutive years; and (2) evaluate the in-field potential of the predatory mite Neoseiulus cucumeris Oudemans (Acari: Phytoseiidae). Monitoring cyclamen mite populations in the field revealed new critical knowledge about its phenology in eastern Canada, such as activity until late November. The predator N. cucumeris was able to effectively suppress cyclamen mites the first year, but appeared to be too cold-sensitive to maintain adequate control towards the end of the season. Furthermore, the high rates of predator release required would most likely be cost prohibitive for commercial use. Control of the cyclamen mite in strawberries remains a complex issue that will require further research.

Strawberry decline disease, predominantly viral in origin, was a serious threat to the strawberry (Fragaria x ananassa Duchesne ex Rozier; Rosaceae) fields of Québec, Canada, between 2012 and 2014. Our aim was to monitor the abundance and activity of the main insect vectors: the strawberry aphid, Chaetosiphon fragaefolii (Cockerell) (Hemiptera: Aphididae) and the greenhouse whitefly, Trialeurodes vaporariorum Westwood (Hemiptera: Aleyrodidae). First, we compared the effectiveness of two trapping techniques, the yellow sticky trap and the yellow pan trap. Results showed that the sticky traps are more effective in capturing alates in flight. Second, we determined the peak flight period for each of the two vectors in several locations within the province of Québec. Results suggest that the peak abundance of winged C. fragaefolii is during the first two weeks of August, while the peak abundance of T. vaporariorum is in the last two weeks of September. Overall trap captures also found 53 different species of winged aphids, and we documented a new distribution record on commercial strawberry fields in Québec, Aleyrodes spiraeoides (Quaintance) (Hemiptera: Aleyrodidae). Species composition and significant information of flight periods will be useful for the management of virus-transmitting insects associated with strawberry decline disease in Québec.

A honey bee (Apis mellifera Linnaeus; Hymenoptera: Apidae) queen’s life expectancy is strongly dependent on the number of sperm she obtains by mating with drones during nuptial flights. Unexplained replacement of queens by the colony and young queens showing sperm depletions have been reported in North America, and reduced drone fertility has been a suspected cause. The aim of this study was to evaluate drone reproductive qualities during the queen-rearing season, from May to August. Drones from two different genetic lines were reared six times during the 2012 beekeeping season at our research centre in Québec (Canada). Semen volume as well as sperm number and viability were assessed at the ages of 14, 21, and 35 days. Results showed (1) a greater proportion of older drones with semen at the tip of the genitalia after eversion; (2) an influence of rearing date on semen production; and (3) no influence of drone genetic line, age or time of breeding on sperm viability. These results highlight the necessity of better understanding drone rearing and how it can be improved to ensure optimum honey-bee queen mating.

Lowbush blueberry (Vaccinium angustifolium Aiton (Ericaceae)) production is highly dependent on insect pollination to maximise yields. The current losses in honey bee (Apis mellifera Linnaeus (Hymenoptera: Apidae)) colonies pose a serious threat to the blueberry industry, raising interest in alternative pollinators. Abundance and diversity of native pollinators usually decreases with distance from natural habitats. In this study, we evaluated the effects of distance from wooded habitats such as windbreaks and forest borders on the presence of native pollinators in blueberry fields in Lac-St-Jean (Québec, Canada). Four treatments were compared: single-row, double-row, natural windbreaks, and forest borders. Pan-traps were placed at 5, 30, and 60 m from the windbreak or forest border. A total of 3878 native pollinators were collected and 81% were ground-nesting bees. The forest border was the only treatment with higher abundance and species richness on the periphery (5 m) of the field than at further distances, supporting the hypothesis that the presence of pollinators is favoured by habitats potentially offering more abundant and diverse nutritional resources. Our overall results reveal that native pollinators are distributed quite homogeneously in blueberry fields, suggesting that windbreaks are beneficial to native pollinator communities.

The small hive beetle (SHB), Aethina tumida Murray (Coleoptera: Nitidulidae), is a non-native pest of honey bees (Apis mellifera Linnaeus (Hymenoptera: Apidae)) newly introduced to Canada. The effectiveness of three in-hive traps was tested in springtime in West-Montérégie (southern Québec, Canada) and in late summer in Essex County (southern Ontario, Canada): AJ’s Beetle Eater™ (AJ’s Beetle Eater), Beetle Barn™ (Rossmann Apiaries), and Hood™ trap (Brushy Mountain Bee Farm). Traps were placed in the brood chamber of 12 colonies in West-Montérégie, and in 48 colonies in the top honey super in Essex County. In-hive traps were effective in reducing SHB populations without compromising the bee population or colony weight gain. In West-Montérégie, the Beetle Barn™ was the most effective trap during the first week, when SHB populations were high. It was less effective when honey bees sealed trap openings with propolis. In Essex County, the AJ’s Beetle Eater™ was the most effective throughout the trial. There was no difference in efficacy between the various solutions used in the Hood™ trap (mineral oil versus mineral oil and apple cider vinegar).