Distribution of <i>Botryosphaeria</i> spp infection in different grapevine nursery materials in New Zealand

Abstract

The aim of this research was to test different grapevine nursery plant materials from different nurseries around New Zealand for presence of Botryosphaeria species Tissue samples (05 cm) were cut from surfacesterilised grapevine stem samples apparently healthy grafted plants failed grafted plants (or Grade 2 plants) scion and rootstock cuttings of different varieties collected from nine grapevine nurseries around New Zealand for isolation onto potato dextrose agar plates The Botryosphaerialike isolates were identified by conidial characteristics and molecular methods Of the propagation materials and plants received 23 had Botryosphaeria infection The majority of Botryosphaeria spp (49) were isolated 1 cm above or below the graft unions of failed/ Grade 2 and Grade 1 plants but also in the scions (10) and the rootstocks (3) of the grafted plants The scion and rootstock cuttings collected from the mothervines had 17 and 21 of the Botryosphaeria infections respectively mostly from the middle and basal parts of the cuttings The distribution of Botryosphaeria spp on different parts of the plants was statistically significant using a Pearson Chisquare test (P<005) These results show that Botryosphaeria species are present in grafted plants in New Zealand indicating that some of the infections in vineyards may originate in the propagation nurseries