Neopestalotiopsis eucalypti, a causal agent of grapevine shoot rot in cutting nurseries in China

Abstract

Grapevine (Vitis vinifera L.) is an economically important fruit crop in the world, and China ranks first in the production of grapes with approximately 15% of the world's total yield. However, diseases that cause the death of grapevine shoots pose a severe threat to the production of grapes. In this study, the fungus Neopestalotiopsis eucalypti was identified as a causal pathogen of grapevine shoot rot based on the morphology of conidia and a phylogenetic analysis. The phylogenetic analysis was performed with three isolates based on the combined sequence of internal transcribed spacer (ITS) region of ribosomal DNA, part of the translation elongation factor 1-alpha (Tef) and the β-tubulin (Tub2) genes. The three isolates were all identified as N. eucalypti. Pathogenicity tests of the three fungal isolates were conducted on grapevines shoots in vitro and in vivo. The results showed that all three fungal isolates caused severe rot lesions on the inoculated grapevine shoots, and N. eucalypti was re-isolated from the inoculated grapevine shoots. Therefore, N. eucalypti was confirmed as a causal agent of the grapevine shoot rot. This is the first report of N. eucalypti causing grapevine shoot disease in China.