Spread parameters of the borer<i>Xylotrechus Arvicola</i>(Olivier) (Coleoptera: Cerambycidae) in a ‘Tempranillo’ vineyard in La Rioja (Spain): A long-term study
Journal
Ciência e Técnica Vitivinícola
ISSN
2416-3953
Date Issued
2020
Author(s)
Rafael Ocete
Ignacio Armendáriz
Carlos A. Ocete
Lara Maistrello
José M. Valle
Álvaro Rodríguez
Leire Usategui
Abstract
<jats:p><jats:italic>Xylotrechus arvicola</jats:italic>(Olivier) (Coleoptera: Cerambycidae) is a polyphagous xylophagous beetle that is becoming a pest of increasing importance for vineyards in Spain, also because of the wood fungi developing in the galleries excavated by its larvae, which cause a progressive decline of the affected grapevines, until death. Between 1993 and 2015, a survey of the infestation caused by<jats:italic>X. arvicola</jats:italic>and the symptoms caused by pathogenic wood fungi was performed in a ‘Tempranillo’ variety vineyard in La Rioja region (Spain). Maps showing the overtime spread of the borer and the diffusion of symptoms of grapevine decline and<jats:italic>Eutypa</jats:italic>dieback were obtained. Results indicated that the borer colonization began in the centre of the plot, followed by the first symptoms caused by the wood fungi a few years later. The statistical analysis showed that the evolution of infestation is characterized by a linear increase of new holes whereas the pattern of their allocation in the vines follows a bimodal distribution which, to some extent, can be simulated by a Poisson’s model. Based on these observations, a methodology to estimate the state of the infestation over time is proposed. The procedure - based on a linear regression of the average number of holes per vine over a set of years - can be applied in a relatively simple way and provides the probability for a grapevine to have a certain number of exit holes in a definite year with a mean error of around 5%.</jats:p>
