Cover crop differentially affects arthropods, but not diseases, occurring on grape leaves in vineyards

Abstract

Background and Aims Cover crop has become a common management practice in viticulture. It improves the structure and protects the soil, enhances natural enemy populations and also reduces the vigour of the vine. Here, we investigated the effect of cover crop in vineyards on grapevine diseases and arthropods present on leaves. Methods and Results We measured the presence of the pathogens Plasmopara viticola, Uncinula necator and Guignardia bidwellii and monitored six common beneficial/pest arthropods: Panonychus ulmi, Orthotydeus lambi, Typhlodromus pyri, Scaphoideus titanus and Phalangium opilio in vineyards with cover crop or bare soil in 2014 and 2015. The density of the two pests P. ulmi and S. titanus and the beneficial mite O. lambi was lower in cover crop, while the density of the beneficial predatory mite T. pyri was higher in cover crop. We found no influence of cover crop on P. opilio and on the presence of grapevine diseases. Conclusions These findings point to a simple way to increase the population of beneficial arthropods and reduce pest arthropods, which could help integrated pest management programs. Significance of the Study To our knowledge, this is the first study monitoring the cover crop influence on both diseases and arthropods. It would help growers to optimise space management between rows to enhance their natural enemy populations while reducing pesticide application.