Anti-GFKV polyclonal antibody

Grapevines from six Chilean regions were surveyed for virus diseases and tested for the presence of the most important viruses. ELISA testing of 2535 samples and confirmatory RT-PCR of some ELISA-negative samples from symptomatic and symptomless vines gave the following infection rates: 6.36% for Grapevine fanleaf virus (GFLV); 4.67% for Grapevine leafroll associated virus 1 (GLRaV-1); 16.05% for Grapevine leafroll associated virus 2 (GLRaV-2); 6.41 % for Grapevine leafroll associated virus 3 (GLRaV-3); 0.26% for Grapevine leafroll associated virus 7 (GLRaV-7); 14.99% for Grapevine fleck virus (GFkV); 5.57% for Grapevine virus A (GVA) and 0.78% for Grapevine virus B (GVB). Strawberry latent ringspot virus (SLRSV) Tomato ringspot virus (ToRSV) and Arabis mosaic virus (ArMV) were not detected. Overall infection in the surveyed Chilean grapevines, considering ELISA and RT-PCR, was 32.35%. Virus infection ratio obtained from ELISA analysis in the six regions, varied between 21.19% (Region Metropolitana) and 74.26% (Coquimbo). RT-PCR was used for detection of the Red Globe strain of GLRaV-2 and Grapevine rupestris stem pitting associated virus (GRSPaV), and to confirm and extend ELISA results. GVB, GFkV, GRSPaV, GLRaV-2 RG and GLRaV-7 are new records for Chile.

Modifications in grape quality parameters induced by mixed infection with GFLV and GFkV, GLRaV-1 and GVA, and GLRaV-3 and GVA in three Nebbiolo clones were compared against healthy plants of the same clones in two experimental vineyards in Piemonte, northwest Italy. The aim of the study was to evaluate the effect of virus infection on the mechanical properties of the berry skin and the whole berry as assessed by texture analysis tests, and on the amount and quality of berry skin phenols. Differences were observed in grapevine vigour, yield and juice composition, depending on the viral status of the plants. The anthocyanin profile of the vines infected with GFV and GFkV and those infected with GLRaV-1 and GVA showed a lower percentage of the more stable tri-substituted malvidin-3-glucoside and a higher percentage of cyanidin and peonidin-3-glucosides. Texture analysis showed that the viruses may increase berry-skin thickness and reduce phenol extractability. These effects carry practical implications for wine quality.