Spray Penetration and Natural Enemy Survival in Dense and Sparse Plant Canopies Treated with Carbaryl: Implications for Chemical and Biological Control1

Abstract

Ornamental plant producers often rely on chemical control to manage insect pests. However, cultural practices, such as pruning, can influence plant architecture which may, in turn, affect pesticide penetration. Spray penetration was studied to determine the effect of canopy density on beneficial insect survival following insecticide application and to better understand the implications of canopy density on pest management. Regardless of canopy density or plant species, the interior position of the canopy received less than 8% spray coverage. The middle position of sparse canopies received 288 to 513% more coverage than the middle position of dense canopies. The middle and interior position of dense canopies protected greater than 50% of the convergent lady beetle (Hippodamia convergens (Guérin-Méneville) population while only the interior position of dense canopies protected greater than 50% of green lacewing (Chrysoperla rufilabris Burmeister) populations. Index words: beneficial insect, nursery crop, pesticide, plant architecture, woody ornamental. Species used in this study: China Girl® holly (Ilex ×meserveae ‘Mesog'); ‘Alice' Oakleaf hydrangea (Hydrangea quercifolia Bartr. ‘Alice'); convergent lady beetle [Hippodamia convergens (Guérin-Méneville)]; green lacewing [Chrysoperla rufilabris (Burmeister)]. Chemicals used in this study: carbaryl (1-naphthyl N-methylcarbamate, Sevin® SL, Bayer CropScience, Durham, NC).

Cultural Control of Drosophila suzukii in Small Fruit—Current and Pending Tactics in the U.S.

“…More open canopies improve harvest efficiency and thus help with sanitation measures by reducing oviposition sites [ 69 ]. Additionally, open canopies receive better spray coverage [ 70 , 71 ]. In conclusion, pruning and trellising can be important components of an IPM strategy, rendering habitats less suitable for D. suzukii while maintaining yield and fruit quality.…”

Effect of the Airblast Settings on the Vertical Spray Profile: Implementation on an On-Line Decision Aid for Citrus Treatments

“…Studies of PPP spray mass balance have reported high spray losses during application [1][2][3][4][5][6][7]. Furthermore, huge variations of spray distribution on the canopies have been observed, because pesticide deposition depends on the vegetation [8][9][10][11][12], equipment [9][10][11][12][13][14], operational parameters [15][16][17][18], weather conditions [19] and spray mix properties [20,21]. PPP losses pose risks both to people (operators, bystanders, residents, etc.)…”