Incidence of grapevine trunk diseases on four cultivars in Sardinia, Southern Italy
DOI:
https://doi.org/10.5073/vitis.2021.60.35-42Keywords:
Botryosphaeria dieback; 'Cabernet Sauvignon'; 'Cannonau'; esca proper; 'Merlot'; 'Sauvignon Blanc'.Abstract
Esca proper and Botryosphaeria dieback are among the most widespread Grapevine trunk diseases (GTDs), characterized by similar decline symptoms. In the present work, chronic, apoplexy and death symptoms were analysed separately in four vineyards and four different cultivars, on more than 1,000 vines per cultivar, taking into account ten-year annual surveys. The cumulative incidence of plants with chronic symptoms (CHR) reached high values on 'Sauvignon Blanc' (81.9 %), 'Cabernet Sauvignon' (79.4 %) and 'Cannonau' (66.5 %), but it was low on 'Merlot' (25.1 %). 'Sauvignon Blanc' showed the highest cumulative incidence of apoplectic events (23.1 %) and dead cordons (49.2 %), while 'Cannonau' had the greatest number of dead plants (28.8 %). In each symptom category, incidence among cultivars differed significantly according to χ2 test at P ≤ 0.05. Annual incidence of foliar symptoms fluctuated over ten years (ranging from 0.9-9.5 % in 'Merlot' to 6.3‑59.1 % in 'Cabernet Sauvignon'), mostly with regard to CHR. On average, every year only 33.9 % of plants showing CHR had expressed symptoms in the previous year, while 48.6 % did not show symptoms the following year. Conversely, most of the plants exhibiting apoplexy or death were symptomatic the previous year. According to Tuckey HSD test (P ≤ 0.05) 'Merlot' had the highest incidence of plants showing CHR symptoms for the first time (72.1 %) and of apparently recovered plants (76.3 %), while 'Cabernet Sauvignon' exhibited the highest incidence of plants showing CHR symptoms also the previous year (50.0 %). The 'Cabernet Sauvignon' attitude to show chronic symptoms with a certain continuity was also confirmed by the low incidence of plants with hidden symptoms (lack of symptoms in previously symptomatic vines). On the contrary, the incidence of acute symptoms (apoplectic events and dead plants) was quite low on 'Cabernet Sauvignon'. The present study confirms that GTD incidence is influenced by cultivar. All the cultivars assessed were susceptible, but with differences in intensity, type (chronic or acute) and fluctuation of symptoms. It cannot be excluded, however, that besides the genotype also external factors, as the vigour conferred by the type of soil or the combination with the rootstock, may have influenced the results.
Downloads
Published
Issue
Section
License
Copyright (c) 2021 The Author(s)
This work is licensed under a Creative Commons Attribution 4.0 International License.
The content of VITIS is published under a Creative Commons Attribution 4.0 license. Any user is free to share and adapt (remix, transform, build upon) the content as long as the original publication is attributed (authors, title, year, journal, issue, pages) and any changes to the original are clearly labeled. We do not prohibit or charge a fee for reuse of published content. The use of general descriptive names, trade names, trademarks, and so forth in any publication herein, even if not specifically indicated, does not imply that these names are not protected by the relevant laws and regulations. The submitting author agrees to these terms on behalf of all co-authors when submitting a manuscript. Please be aware that this license cannot be revoked. All authors retain the copyright on their work and are able to enter into separate, additional contractual arrangements.