DISEASE SUPPRESSIVENESS OF VINEYARD SOILS INFESTED WITH GRAPE PHYLLOXERA
The aim of this study was: (i) to investigate the occurrence of soilborne fungal pathogens in vineyards, (ii) to study the interactions of these pathogens with phylloxera tolerant rootstocks, and (iii) to gain basic data for the development of control strategies. The trials focused on the relationship between an infestation of rootstock roots with grape phylloxera and damage to vine growth. Microbial community structures and activities in compartments of soils and roots were investigated and correlated with abiotic and biotic soil parameters. The background hypothesis was that the vineyard soils with and without vine growth damages are different in their suppressiveness against plant pathogens. The trial sites were established on phylloxera infested vineyards of the Department for Grapevine Breeding and Grafting of the Geisenheim Research Centre to investigate the influence of mineral and organic fertilizers on health of grapevines in 1998. A vineyard without grape phylloxera infestation served as the control. Qualitative and quantitative aspects of microbial communities in soil and root samples were analyzed. It was demonstrated that obligate and facultative fungal parasites are very common in all investigated vineyards. However, the soils of sites with and without vine damages differ in community structure of soil fungi, microbial biomass, activities of microorganisms or soil-pH. This implies, that the suppressiveness of vineyard soils with phylloxera infestations determine if vines will be damaged or not. Suppressiveness of vineyard soils could be correlated to soil management strategies such as application of organic matter.
Huber, L., Hoffmann, M., Rühl, E.H. and Kirchmair, M. 2009. DISEASE SUPPRESSIVENESS OF VINEYARD SOILS INFESTED WITH GRAPE PHYLLOXERA . Acta Hort. (ISHS) 816:41-52
soil fungi, microorganisms, pathogens, integrated pest management