Validating the use of a laser-guided intelligent sprayer for management of Japanese beetles on grapes

Japanese Beetles (JB) are one of the most common pests attacking grapevines. They typically appear in the vineyard around bloom and persist through veraison, damaging foliage at its most vulnerable stages.  Growers typically spray insecticides with conventional, constant-rate airblast sprayers, which apply excessive pesticides, resulting in costly over spraying and risks to the environment. However, a more sustainable alternative exists in laser-guided, variable-rate intelligent sprayer technology (IST), which visualizes canopy architecture to optimize spray volume based on vine height, width, spacing, and density.

The goal of this study was to compare the efficacy of JB management on grapevines using either airblast or IST systems.  We applied the insecticide Sevin 4F to grapevines using an airblast sprayer or an airblast sprayer equipped with IST.  We assessed JB damage by evaluating five terminal leaves on five randomly selected shoots in each plot for the presence of skeletonized leaves.  Herbivory was highest in non-treated plots (P=0.002), but there was no difference in JB herbivory on grapevines treated with either airblast or IST systems.  Although grape yields were statistically similar across airblast and IST treatments (P=0.0572), yield from the IST treatment was, overall >2000 lb/A greater than that from the airblast sprayer.  Furthermore, IST used five times less insecticide volume than the airblast sprayer (P=0.0161) such that using IST in the vineyard was twice as profitable compared to the airblast system without IST.  Thus, IST successfully managed Japanese Beetles on grapevines and proved to be just as effective as the airblast sprayers.