Grapevine crown gall detection by electronic nose

A commercial electronic nose (e-nose) was used to discriminate healthy grapevine tissue from crown galled ones. Samples were collected from outdoor trials and from a nursery. Experimental samples were obtained by grapevine inoculation with Agrobacterium vitis suspensions: samples were collected after 9 months (young rootstocks) and 4 years (aged rootstocks). Field samples (1-year old shoots) were provided by Emilia Romagna Phytosanitary Service (Italy). E-nose analysis was carried out on rootstock and shoot segments. Samples were distributed in the principal component analysis score plot in two areas: on the left, healthy samples and those with small tumors were grouped, whereas high disease severity samples were localized on the right. Linear discriminant analysis correctly classified the samples with a total recognition percentage of 79%. The data obtained allowed building a database in which different sizes, organs, and disease severity of samples are taken into consideration.