Evaluation of crown gall resistance in Vitis vinifera and hybrids of Vitis spp.

Relative levels of crown gall susceptibility were determined in 17 genotypes of Vitis spp. by inoculating a diverse set of Agrobacterium vitis strains, measuring gall size and weight, and percentage of inoculated sites with galls. Hybrids of Vitis vinifera cv. Jighjigha x Vitis riparia “Gloire” (NAZ4) and V.vinifera cv. Alibaba x 110 R (NAZ5) were the most resistant genotypes but not completely immune. No genotype of V. vinifera was immune to crown gall. The interactions among strain and genotype were significant. V. vinifera cv. White Bidaneh was especially sensitive to the limited host range strain AG57. Weight and size of galls that were induced by 4 strains of Agrobacterium vitis were not significantly different for all genotypes of Vitis spp. But susceptibility of the genotypes to individual strains of A. vitis were significantly different