Composted winery waste and its influence on grape Phylloxera in ungrafted vineyards

A field-based study was conducted over three consecutive grapevine growing seasons in the hot climate Nagambie region of Central Victoria, Australia. The study assessed the effect of composted winery waste (grape mare or pomace) on the population dynamics and risk of dispersal of root-feeding grape phylloxera Daktulosphaira vitifoliae on ungrafted Vitis vinifera 'Semillion' grapevines. Grape yield and quality was also assessed to determine the effect of compost application. Root-galling populations of phylloxera, assessed in winter and late summer were not significantly affected by application of composted grape marc. Phylloxera emergence at the soil surface was significantly reduced by a single application of two composted marc formulations. The implications of these results for phylloxera management on ungrafted V. vinifera grapevines, and reuse of winery waste in phylloxera-infested regions is discussed.