Lobesia botrana males mainly fly at dusk: video camera-assisted pheromone traps and implications for mating disruption

Pheromone-mediated mating disruption (MD) is currently considered an effective strategy to control the European grapevine moth (EGVM), Lobesia botrana, with a successful interference on natural female calling during the male searching flight. However, little is known on the impact of the hour of the day on EGVM male flight. While various models forecasting the day of maximum presence of males per flight have been developed, field research on the male flight activity over 24 hours is scarce. Hence, we used video camera-assisted pheromone traps to allow a continuous monitoring of EGVM flights over daylight and night hours, quantifying captures of males. Experiments were carried out in three vineyards located in northern Spain over two years (2016 and 2017). Results showed that EGVM flight mainly occurred between 21:00 and 23:00 h (GMT+1, daylight saving time). Furthermore, male catches significantly differed over the study year, annual flight period and vineyard. Most of the dispensers used worldwide for EGVM MD continuously release the main sex pheromone component [(7E,9Z)-7,9-dodecadien-1-yl acetate], except for some automatic devices releasing puffs of sex pheromones at selected time intervals. The findings presented here can be useful to optimize the MD technique, identifying selected time intervals when the release of EGVM synthetic pheromones can be concentrated, boosting MD efficacy against this important pest, minimizing the release of synthetic sex pheromone molecules in the environment and reducing application costs.