Testing Biological Controls for \u3cem\u3eHeliothrips haemorrhoidalis\u3c/em\u3e (Thysanoptera: Thripidae), a Serious Pest of the Morris Arboretum Greenhouse Complex

The greenhouse thrips (Heliothrips haemorrhoidalis) is a serious pest of fruits and ornamental plants. In the Morris Arboretum’s greenhouse complex, this thrip has been prevalent, and could cause major damage to the young plants that are being propagated. The purpose of this project was to search for a suitable biological control of the thrips since chemicals have only been marginally effective. A predatory spider mite (Amblyseius cucumeris) and minute pirate bugs (Orius insidiousus) were chosen for the study. The results suggest that the minute pirate bugs are highly effective at hunting thrips, while the spider mites had no measurable effect

Blueberries infected with the fungal pathogen Colletotrichum fioriniae release odors that repel Drosophila suzukii

Spotted-wing drosophila, Drosophila suzukii, is a serious pest of thin-skinned fruits. Alternative methods to control this pest are needed to reduce insecticide use, including new repellents. Previous research demonstrated that D. suzukii adults use odor cues to avoid blueberries infected with the fungal pathogen Colletotrichum fioriniae, which causes the disease anthracnose. To identify novel D. suzukii repellents, we investigated the volatile emission from experimentallyinfected fruit, which were inoculated with C. fioriniae isolates in the laboratory, and from field-collected fruit, which were naturally infected and harvested from a field. We then tested the pathogen-induced volatiles on D. suzukii adult behavior.hanks to Arthur Rudolph for his help operating the GC–MS during pandemic work restrictions, Chelsea Abegg for providing field-collected blueberry fruit infected with anthracnose, to Mustafa Wasti, Robert Holdcraft, and Vera Kyryczenko-Roth for technical assistance. Authors CCR and JJB were supported by USDA ARS CRIS 6036-224300-001-000D and CR-S and AQ were supported by USDA SCRI 2020-51181-32140, The Sridhar Polavarapu Memorial Endowment for Vaccinium Research, and USDA Sustainable Agriculture Research and Education (grant no. LNE22-455R).info:eu-repo/semantics/publishedVersio

Elicitors of plant defenses as a standalone tactic failed to provide sufficient protection to fruits against spotted-wing drosophila

Spotted-wing drosophila, Drosophila suzukii (Matsumura), is a globally important invasive pest of soft-skinned fruits including raspberries, blueberries, and strawberries. Current control measures for this pest primarily rely on calendar-based insecticide sprays; therefore, more sustainable methods are desirable. Adults of D. suzukii use cues derived from fruits and symbiotic microbes to identify optimal sites for feeding, mating, and oviposition. We hypothesized that modifying any of these cues could influence D. suzukii adult behavior, making them less likely to select suitable fruits. One approach involves applying synthetic elicitors of the salicylic acid (SA) and jasmonic acid (JA) plant defense pathways, which are associated with defenses against pathogens and herbivores, respectively, or the use of crop sterilants, employed for microbial control, to reduce D. suzukii attraction, oviposition, and larval performance in fruits. Here, the preference and performance of D. suzukii was investigated in blueberry fruits treated exogenously with four commercial elicitors of plant defenses – three that primarily activate SA-related defenses (Actigard, LifeGard, and Regalia) and one activator of JA-related defenses (Blush) – and the crop sterilant OxiDate. A series of choice and no-choice experiments were conducted in laboratory, semi-field, and field settings that were performed at various time intervals to assess the residual effects of each treatment. Our results showed no consistent repellent, oviposition deterrent, or larval toxicity activity for any of the products tested. As a result, our findings do not provide sufficient support to recommend the use of these elicitors or the crop sterilant as viable standalone options for D. suzukii management.info:eu-repo/semantics/publishedVersio