Foliar application of entomopathogenic nematodes for the control of vine mealybug (Planococcus ficus) in vineyards
The grapevine mealybug, Planococcus ficus (Hemiptera: Pseudococcidae), is the dominant mealybug on grapevines in South Africa. It causes direct damage to wine and table grapes and it is the primary vector of grapevine leafroll virus. The risk of developing resistance to insecticides and consumer demands for sustainably produced, residue-free fruit have led to a search for alternative control methods.
Mealybug management currently relies heavily on chemical control. Success is hampered by the inability of the chemicals to come into direct contact with the mealybugs because of their wax secretions and cryptic habits. Chemical control before budding is often not possible because vineyards are waterlogged and post-harvest chemical control is harmful to natural enemies. Entomopathogenic nematodes (EPNs) belonging to the families Heterorhabditidae and Steinernematidae, have been shown to be effective against grapevine mealybugs in laboratory studies. Application of EPNs to grapevines after harvest or in autumn when leaves have fallen would provide an environmentally acceptable alternative to insecticide applications before budding for mealybug control.
The aim of this project is to investigate the use of EPNs to control grapevine mealybug on the leaves, cordon arms and stems of grapevines. The ultimate aim is to incorporate the use of EPNs in an IPM system for mealybug.