Submitted to: BMC Research Notes
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/7/2022
Publication Date: 6/20/2022
Citation: Wallis, C.M. 2022. Potential effects of Grapevine leafroll-associated virus 3 or Grapevine red blotch virus infection on foliar phenolic and amino acid levels. BMC Research Notes. 15. Article 213. https://doi.org/10.1186/s13104-022-06104-1.
Interpretive Summary: Grapevine leafroll-associated virus 3 (GLaV-3) and Grapevine red blotch-associated virus (GRBaV) infections of grapevine significantly reduce yield and fruit quality over time, resulting in vineyard replanting. Changes in physiology are likely associated with such reductions, but measurements of phenolic and amino acid compounds in foliage have not been comprehensively done. Therefore, total phenolic and amino acid levels were measured in grapevines grown on different rootstocks that were healthy or infected at three times during the growing seasons of 2018 and 2019. Results showed that viral infections did not cause as much variation in phenolic and amino acid levels as sampling time or rootstock cultivar, albeit specific phenolics were lower in infected than healthy plants. For amino acids, overall levels were greater in plants infected with GLaV-3 than healthy plants but did not differ among healthy and GRBaV infected vines. These results improve understanding of viral infection progression in grapevines and suggest host chemistry diagnostics would be difficult to develop.
Technical Abstract: Grapevine (Vitis spp.) viral infections, including those by Grapevine leafroll-associated virus 3 (GLaV-3) and Grapevine red blotch-associated virus (GRBaV), greatly reduce yield and fruit quality. Evidence exists that host chemistry shifts result in reductions in fruit quality. However, changes over the season in foliar chemistry has not been well examined. Therefore, phenolic and amino acid levels were examined in leaves collected in grapevines with different rootstocks that were healthy or infected with GLaV-3 or GRBaV. Month and year accounted for the greatest variability in grapevine foliar phenolic or amino acid levels, followed by differences in rootstock type, and then differences in infection status. GLaV-3 infection significantly lowered levels of total and individual hydroxycinnamic acid derivatives, and GRBaV infection lowered total phenolic levels, total and individual hydroxycinnamic acids. Amino acid levels were increased over controls in vines infected by GLRaV-3, but not with GRBaV. Overall, changes within grapevine leaves due to viral infection were likely too small to overcome variability due to sampling time or rootstock cultivar, and therefore diagnostics to determine infection status based on analyzing foliar chemistry would be difficult.