Impact of mycorrhizal colonisation on grapevine establishment in <i>Cylindrocarpon</i> infested soil

Abstract

The effects of arbuscular mycorrhizae (AM) Glomus mosseae and Acaulospora laevis on growth of six grape rootstock varieties and their infection by Cylindrocarpon species were investigated in a greenhouse experiment that challenged the mycorrhizal plants with a mixed inoculum of Cylindrocarpon spp Both species of AM had beneficial effects (P<005) on rootstock growth but this effect was specific for particular rootstock and AM combinations Generally G mosseae had a more consistent positive effect and A laevis was the only species to decrease plant growth in some rootstock varieties Subsequently two field trials conducted in Auckland and Blenheim used a mixture of the two AM species and two rootstock varieties After 9 months compared to control plants mycorrhizal plants had similar incidence of Cylindrocarpon infection at both sites (P>005) but greater root dry weights in Auckland (214; P<005) and Blenheim (only 22; P>005) G mosseae clearly has potential for improving health and growth of young grapevine plants