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Grape berry moths, particularly Lobesia botrana Denis & Schiffermüller (Lepidoptera: Tortricidae), and vinegar flies, such as Drosophila melanogaster Meigen and Drosophila suzukii Matsumura (Diptera: Drosophilidae), are important vineyard pests, causing severe quality loss of grapes. Several arthropod taxa may be involved in the natural control of these pests. However, the role of arthropod predators in the natural control of vineyard pests remains unclear. We investigated 32 vineyards in the Palatinate region, southwest Germany, under organic and conventional management, which in both cases received either full or reduced fungicide applications (2 × 2 design). Predation of L. botrana eggs and pupae and D. melanogaster pupae on sentinel cards exposed in the vineyards was observed with infrared cameras. In total, nine predator taxa could be identified. The most dominant predator was the European earwig, Forficula auricularia L. (Dermaptera: Forficulidae), with 90% of all predation events. We conclude that F. auricularia is likely a key predator of vineyard pests, and that special attention should be paid to maintain it at high population densities. [ABSTRACT FROM AUTHOR]

The European grapevine moth (Lobesia botrana) is currently the most damaging pest in many viticultural regions of South and Central Europe and is highly responsible for the development of secondary infections by Botrytis cinerea to both table and wine grapes. Entomopathogenic fungi (EPF) are considered as substantial biological control agents of insect pests. However, they are able to infect their hosts only under a narrow spectrum of environmental conditions. In this study, the effects of temperature on pathogenicity of EPF for the control of L. botrana are reported. Among a collection of 33 EPF isolates, six virulent isolates were selected for the experiments. The bioassays took place at controlled conditions, under the temperature regimes of 20, 22.5, 25, 27.5, 30, and 32.5 °C. A conidial concentration of 1 × 108 conidia/ml was prepared for each isolate, and fungi were applied by spraying them on third-instar larvae (L3) of L. botrana. Both factors, fungal isolate and temperature, significantly affected mortality of L. botrana. Most fungal isolates exhibited their highest larval mortality rates seven days post-treatment at the temperatures of 25 and 27.5 °C. Some isolates caused considerably high larval mortality that exceeded 90% under specific temperature conditions. Overall, EPF showed great potential as bio-control agents for controlling larval populations of L. botrana. [Display omitted] • Entomogenous fungi showed great potential as biocontrol agents of Lobesia botrana. • Temperature significantly influenced all fungi on larval mortality of L. botrana. • An isolate from a cool region (Isaria fumosorosea EBAC01) was the most virulent. • Most fungal isolates demonstrated their highest efficacy at 25 and 27.5 °C. [ABSTRACT FROM AUTHOR]

The vine mealybug, Planococcus ficus, is a global pest of grapes, leading to lower yields and transmission of damaging viral pathogens. Insecticides are the predominate method of P. ficus management, but some pesticide options have been lost in many of the world's vineyard regions and other economically viable options are now critically needed. Mating disruption is commercially available for P. ficus , however recommended deployment rates can be costly. To reduce costs, the effectiveness of lower dispenser deployment rates should be fully explored. In 2018–2019, we tested a novel high-density passive dispenser at 494 dispensers per ha. In 2020–2022 variable rates of the high-density dispenser were tested and a novel meso passive dispenser at variable rates was also tested in separate trails. An insecticide was applied to all treatments in 2018–2019 and to two of four blocks in 2020. All trials occurred in central California, US. The high-density dispensers (494 dispensers per ha) reduced male P. ficus captures and crop damage in both years. High-density dispensers at variable deployment rates (62–370 dispensers per ha) and meso dispensers (62–270 dispensers per ha) reduced P. ficus trap captures, with increasing dispenser density decreasing trap captures. Crop damage, amount of P. ficus per grape cluster, was significantly reduced only in the second year of the meso trial. Mating disruption is an effective method of suppressing P. ficus and current recommend rates could be lowered, which would reduce costs for growers and increase adoption of this sustainable tactic. • Mating disruption dispensers reduced Planococcus ficus trap catches with little to no insecticide application. • Mating disruption dispensers caused season long trap shutdown in three of the six trial/years. • One dispenser application was enough to affect trap catches for the entire season. • Grape cluster infestations were only reduced by mating disruption in one year. [ABSTRACT FROM AUTHOR]

Simple Summary: The vine mealybug is a key insect pest of vineyards that currently is controlled by one or more insecticide applications per season. Here, we sought to develop a more sustainable control tool by using the mealybug's sex pheromone to reduce mating and thereby lower pest damage. The mature female mealybug emits a sex pheromone that the winged adult male uses to find and mate with females. Synthetically produced sex pheromone, specific to the vine mealybug, was enclosed in commercial dispensers and deployed in vineyards in 2004–2007 studies to determine if mating disruption could provide a viable control option. Trials were conducted in commercial vineyards with cooperating farmers. Across all trials, mating disruption reduced pheromone trap captures of adult male mealybugs—an indication that the population numbers were lowered—and there was often a reduction mealybug numbers on vines and/or crop damage. There was not a clear reduction in the proportion of female mealybugs with ovisacs (a cottony-like mass containing mealybug eggs), but this may have resulted from the production of non-viable ovisacs that were not differentiated in the field samples. Pheromone trap captures were never lowered to zero (often called trap shut down), possibly because trials were conducted in vineyards with unusually high mealybug densities. Trap capture patterns commonly began low in April-May, increased in mid-July or August, and often decreased in September–October when post-harvest insecticides were applied. Results over all years suggest season-long coverage or late season coverage may be as or more important than dose per hectare. This research was used to help initiate the commercialization of mating disruption products for the vine mealybug, which are now being successfully used throughout the world's grape-growing regions where this pest is found. The vine mealybug (VMB), Planococcus ficus (Hemiptera: Pseudococcidae), is a key insect pest of vineyards, and improvements in sustainable control of this pest are needed to meet increasing consumer demand for organically farmed products. One promising option is mating disruption. In a series of experiments conducted from 2004 to 2007, we tested the effects of mating disruption on trap captures of Pl. ficus males in pheromone-baited traps, on Pl. ficus numbers and age structure on vines, and on damage to grape clusters. From 2004 to 2005, the effects of dispenser load (mg active ingredient per dispenser) were also assessed, and dispensers were compared to a flowable formulation. Across all trials, mating disruption consistently reduced pheromone trap captures and often reduced mealybug numbers on vines and/or crop damage, regardless of the pheromone dose that was applied. Reductions in Pl. ficus densities in mating disruption plots were not accompanied by clear effects on mealybug population age structure; however, production of non-viable ovisacs by unmated females may have obscured differences in proportional representation of ovisacs. Pheromone trap captures were never lowered to zero (often called trap shut down), possibly because trials were conducted in vineyards with unusually high Pl. ficus densities. Trap-capture patterns in both treated and control plots commonly began low in April–May, increased in mid-July or August, and often decreased in September–October when post-harvest insecticides were applied. During the four-year trial, the release rate from plastic sachet dispensers was improved by industry cooperators as pheromone was released too quickly (2004) or not completely released during the season (2005–2006). The flowable formulation performed slightly better than dispensers at the same application dose. Results over all years suggest season-long coverage or late-season coverage may be as or more important than dose per hectare. Development of a dispenser with optimized season-long pheromone emission or targeted seasonal periods should be a future goal. [ABSTRACT FROM AUTHOR]