untitled


109

Prevention and control strategies against Agrobacterium vitis in 
grapevine multiplication material

G. Lucchetta1, G. Bevilacqua2, C. Colla3, S. Di Marco4, R. Falconi2, C. Frausin5, R. Mirandola2, G. Mor-
denti4, E. Sartori6, E. Angelini1

1 CRA-VIT, Centro di ricerca per la Viticoltura, Conegliano (TV), elisa.angelini@entecra.it.
2 VITIVER Consorzio per la Valorizzazione dei Prodotti Ortoflorovivaistici Veronesi, Verona.
3 MIVA Moltiplicatori Italiani Viticoli Associati, Firenze.
4 CNR IBIMET, Bologna.
5 ERSA Agenzia Regionale per lo Sviluppo Rurale, Pozzuolo del Friuli (UD).
6 VCR Vivai Cooperativi Rauscedo, Rauscedo (PN).

Agrobacterium vitis is the etiological agent of grapevine crown gall disease, an abnormal tissue growth occurring 
mostly in the basal part of the trunk. The infection starts at wound sites and it is often caused by freezing temperature. The 
pathogen does immediately not cause the tumour, but it can stay latent in the plant for a long time, without clear damage. 
Infections occurring in the first years of planting lead to debilitation of infected grapevines, together with poor quality 
and quantity of grape production.

In Italy in the last three years crown gall, a disease already known previously, has shown an unexpected increase, es-
pecially due to the cold temperatures in the 2009-2010 winters. This spread has caused serious damage for nurserymen, 
and the consequences continue now: grape growers are complaining about crown galls in one-year-old vineyards, and 
foreigner importers are asking for A. vitis-free rootlings.

Unfortunately, control strategies applied at present are successful in decreasing the damage but not in eliminating the 
pathogen. For these reasons, CRA-VIT, together with ERSA and several nurserymen (VITIVER, VCR, MIVA), is study-
ing this disease in order to identify critical points in the grapevine production process and possible solutions to control 
the infection in mother plants and in nurseries. 

The research activities include: i) monitoring of soils and mother plants in the Verona area; ii) monitoring and optimi-
zation of procedures in the grapevine production chain; iii) experimental trials to verify the effectiveness of Trichoderma 
spp. treatments of grafts and rootlings; iv) cleaning of multiplication material by chemical or alternative agents; v) hot 
water treatments; and vi) molecular characterization of A. vitis strains in order to establish molecular markers for trace-
ability of infection sources.

Hot water treatments, unfortunately, are completely ineffective in obtaining bacterium-free rootlings (Lucchetta et al., 
2013), while initial analyses of soils and mother plants in the Verona area have been encouraging; cleaning trials with 
acidic water and Virkon need further study. Other experimental trials are ongoing and initial results will be outlined in 
the presentation. 

Acknowledgements

This work is financed by AGRO.FREE project (PSR Regione Veneto 2012-14), ERSA, MIVA and VCR. We are grate-
ful to the CRA-VIT staff, the nurserymen involved and CBC Europe for the collaboration.

References

LUCCHETTA G., MIOTTI L., FORTE V., SARTORI E., ANGELINI E., 2013 - Per il tumore della vite la termoterapia non funziona. 

- L’Informatore Agrario, 17: 55-58.

Adv. Hort. Sci., 2013 27(3): 109