Grapevine production has been endangered by several diseases against which control methods are not available. Viruses, phytoplasmas, bacteria and fungal infections contributing to esca have significant importance all over the world. These pathogens systemically infect their hosts, thus the use of healthy propagating material is a key factor in the prevention of disease development. Selection of pathogen-free plant material can be achieved by testing for the presence of pathogens. For virus identification a complex protocol including serological and molecular methods followed by testing on indicator plants is used. For the detection of phytoplasmas, bacterial and fungal infections, polymerase chain reaction (PCR) has become the most widely used method. Various treatments and alternative propagation methods can also be used to clean plant material from latent infections. To eliminate viruses, plants are first heat treated followed by in vitro multiplication of shoot tips. This protocol is suitable for the efficient elimination of other (phytoplasmas, bacteria and fungi) systemic infections. Agrobacterium-free plant material can also be obtained by rooting shoot tips in the greenhouse. Hot water treatment of dormant canes has been successfully used to eliminate
phytoplasmas, partially A. vitis and several other pathogens and pests.
Key words: Vitis, viruses, phytoplasmas, Agrobacterium, esca, in vitro culture, heat treatment