ON THE POSSIBLE RELATIONSHIP BETWEEN KOBER STEM GROOVING AND GRAPEVINE VIRUS-A

Investigations were carried out to establish possible correlations of two diseases of the rugose wood complex, i.e. Rupestris stem pitting ( RSP) and Kober stem grooving (KSG) with grapevine virus A (GVA) and gr apevine leafroll associated viruses I (GLRaV I) and III (GLRaV III). T o this purpose 84 clonal accessions of different wine grape cultivars were analyzed by ELISA and by indexing onto the indicators Vitis rupes tris, Kober 5BB and LN 33. The results obtained clearly indicated that none of the viruses taken into consideration is apparently involved i n the etiology of RSP. Conversely, a remarkably close association of G VA with KSG was discovered.