The Effect of Hot-Water Treatment on Fungi Occurring in Apparently Healthy Grapevine Cuttings

Abstract

Many grapevine nurseries are presently employing a hot-water treatment for propagation material as a prophylactic measure. The aim of this study was thus to determine the efficacy of this treatment in eliminating fungal endophytes from grapevine cuttings. The number of fungal colonies isolated from the hot-water treated cuttings 6 months after planting were not, however, significantly different (P=0.05) from that of the untreated cuttings. This was in contrast to where isolations were made directly after treatment, when no known living fungal pathogens were found inside treated vine tissue. These results therefore indicate that the hot-water treatment is effective in eliminating the most well-known fungal pathogens and endophytes from grapevine tissue. Further research now needs to be focused on combining this treatment with biological control agents in an attempt to delay recolonisation of tissue by fungal pathogens.