Mini munchers to control powdery mildew and botrytis bunch rot in grapes

Abstract

The use of mycophagous (fungal feeding) invertebrates has potential to contribute to disease management in both organic and conventional wine production systems in New Zealand The New Zealand wine industry is actively working towards producing ultralow residue wines This involves removing all late season botrytis fungicide sprays from the vineyard spray programme In organic wine production systems in New Zealand the only products available to control powdery mildew and botrytis bunch rot are protectants In both these systems when fungicides are not available mycophagous invertebrates may reduce the amount of inoculum available to cause disease A survey of leaf material in 19 vineyards in Canterbury and Marlborough over the 20082009 growing season identified populations of beetles in two vineyards in sufficient numbers to justify further research In the laboratory fieldcollected beetles that were starved for 2 days fed on spores of Botrytis cinerea (botrytis bunch rot) growing on blackcurrant flowers Podosphaerea leucotricha (apple powdery mildew) on apple leaves and Erysiphe necator (grape powdery mildew) on grape leaves Beetles were identified as Aridius bifaciatus (Reitter) A nodifer (Westwood) and Cortinicara hirtalis (Broun)