Impacts of Grapevine Leafroll Disease on Fruit Yield and Grape and Wine Chemistry in a Wine Grape (Vitis vinifera L.) Cultivar

PLoS One. 2016 Feb 26;11(2):e0149666. doi: 10.1371/journal.pone.0149666. eCollection 2016.

Abstract

Grapevine leafroll disease (GLD) is an economically important virus disease affecting wine grapes (Vitis vinifera L.), but little is known about its effect on wine chemistry and sensory composition of wines. In this study, impacts of GLD on fruit yield, berry quality and wine chemistry and sensory features were investigated in a red wine grape cultivar planted in a commercial vineyard. Own-rooted Merlot vines showing GLD symptoms and tested positive for Grapevine leafroll-associated virus 3 and adjacent non-symptomatic vines that tested negative for the virus were compared during three consecutive seasons. Number and total weight of clusters per vine were significantly less in symptomatic relative to non-symptomatic vines. In contrast to previous studies, a time-course analysis of juice from grapes harvested at different stages of berry development from symptomatic and non-symptomatic vines indicated more prominent negative impacts of GLD on total soluble solids (TSS) and berry skin anthocyanins than in juice pH and titratable acidity. Differences in TSS between grapes of symptomatic and non-symptomatic vines were more pronounced after the onset of véraison, with significantly lower concentrations of TSS in grapes from symptomatic vines throughout berry ripening until harvest. Wines made from grapes of GLD-affected vines had significantly lower alcohol, polymeric pigments, and anthocyanins compared to corresponding wines from grapes of non-symptomatic vines. Sensory descriptive analysis of 2010 wines indicated significant differences in color, aroma and astringency between wines made from grapes harvested from GLD-affected and unaffected vines. The impacts of GLD on yield and fruit and wine quality traits were variable between the seasons, with greater impacts observed during a cooler season, suggesting the influence of host plant × environment interactions on overall impacts of the disease.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Anthocyanins / analysis
  • Closteroviridae / isolation & purification*
  • Fruit / chemistry*
  • Fruit / virology
  • Phenols / analysis
  • Plant Diseases / virology*
  • Vitis / chemistry*
  • Vitis / virology
  • Wine*

Substances

  • Anthocyanins
  • Phenols

Grants and funding

This study was funded, in part, by the Agriculture Research Center, Washington State University College of Agriculture, Human and Natural Resource Sciences, the Wine Advisory Committee, the Washington Wine Commission, and Washington State Grape & Wine Research Program, USDA-NIFA-Specialty Crop Research Initiative (Award No. 2009-51181-06027) and USDA Northwest Center for Small Fruits Research. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.