Grapevine Red Blotch Virus May Reduce Carbon Translocation Leading to Impaired Grape Berry Ripening

Abstract

Grapevine red blotch virus (GRBV) is suspected to alter berry ripening and chemistry. This study performed a physiological characterization of GRBV infected grapevines with attention to the factors leading to chemical changes during ripening of Cabernet Sauvignon in two rootstocks, 110R and 420A. RB­(+) grapevines had transiently lower net photosynthesis; however, berry total soluble solids (TSS) accumulation was consistently reduced in the two years of study. Accumulation of anthocyanins and loss of titratable acidity and proanthocyanins were also delayed in RB­(+) plants. However, the comparison of samples with the same TSS led to lower pH and anthocyanins content. The reduction in carbon import into berries under mild and transient reductions in carbon fixation suggested an impairment of translocation mechanisms with RB­(+), leading into a desynchronization of ripening-related processes.

The impact of grapevine red blotch disease on Vitis vinifera L. Chardonnay grape and wine composition and sensory attributes over three seasons

“…RB(+) grapes were 4.2%, 8.2%, and 4.4% °Brix lower than RB(−) grapes at harvest in 2014, 2015 and 2016 seasons, respectively. These results confirmed what was found in other studies regarding the impact of GRBD on grape sugar concentration in red cultivars . The reduced accumulation of sugar has been demonstrated to be one of the most typical impacts of viral diseases in grapevines .…”

“…Another study showed that berry weight was higher in grape berries from V. vinifera L Albariño grapevines infected by GLRV . However, in Cabernet Sauvignon, no impact was observed regarding berry weight from grapevines infected by GRBV . Unfortunately, the number of berries per cluster was not determined in this study.…”

“…Grape berry development and metabolism were shown to be altered due to GRBV infection by interfering with transcription and hormonal regulation of ripening in Zinfandel grapes, including abscisic acid, a hormone closely related to the start of sugar accumulation at veraison . Another study concluded that the reduction in carbon import from leaves into berries under mild and transient decreases in carbon fixation suggested an impairment of translocation mechanisms with GRBV leading into a desynchronization of ripening‐related processes …”

“…Similar to other viruses known for causing negative impacts on grapevine physiology and fruit quality, GRBV was shown to impact grapevine leaf metabolism, reduce yield and pruning weight, decrease grape sugar and color accumulation, and alter transcription factors and hormone networks during grape ripening . To date, limited information is available regarding the effects of GRBD on wine composition, sensory properties, and consumer perception.…”

“…Seasonal conditions may also influence how GRBD impacts grape composition . Environmental and weather parameters such as air temperatures, growing degree days (GDD), precipitation, and light may modify not only grape and wine composition from 1 year to another but also alter the interaction between GRBV and the grapevines.…”