Naslov
A case study of FD and BN phytoplasma variability in Croatia: multigene sequence analysis approach

Autori
Plavec, Jelena ; Križanac, Ivana ; Budinšćak, Željko ; Škorić, Dijana ; Šeruga Musić, Martina

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
XVIII. International Plant Protection Congress (IPPC) 2015 Abstract book / - Berlin, 2015, 157-157

Skup
XVIII. International Plant Protection Congress (IPPC) 2015

Mjesto i datum
Berlin, Njemačka, 24.08.2015. - 27.08.2015

Vrsta sudjelovanja
Predavanje

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
MLST; genotyping; GY; epidemiology; phytoplasma; Croatia

Sažetak
Introduction Uncultivable bacteria from the genus 'Candidatus Phytoplasma' are associated with grapevine yellows (GY) diseases worldwide. In Euro-Mediterranean viticultural areas, GY are the most frequently caused by Bois Noir (BN) phytoplasmas, recently assigned to ‘Ca. P. solani’ species, and Flavescence Dorée (FD) phytoplasmas. Surveys of GY in Croatia have been continuously conducted since 1997, with BN being widespread, and recently discovered FD being present in restricted areas of the country. Objectives The aim of this research was to assess the variability of genotypes involved in GY pathosystems by using multilocus sequence typing (MLST) approach on a limited number of samples as well as to evaluate the MLST analysis in finer discrimination between closely related strains. Materials and methods Grapevine, weed and insect vector samples were collected from three locations in continental Croatia (central and north western part). All samples were tested by conventional PCR/RFLP assays amplifying phytoplasma 16S rDNA. In order to simultaneously detect FD and BN phytoplasmas in the infected grapevine, TaqMan triplex real-time-PCR assay amplifying house- keeping gene map was also performed. Species- specific stamp and vmp1 genes together with house-keeping genes tuf and secY were amplified and sequenced from BN strains. In FD strains, secY, map and uvrB-degV genes were analyzed. Results MLST encompassing phylogenetic analyses and/or RFLP analyses revealed a diversity of BN genotypes, with one being prevalent and identified from both grapevine and the insect vector Hyalesthes obsoletus, corroborating their affiliation to the same pathosystem. Distinct BN strains found in bindweed and two grapevine samples indicated the presence of different BN pathosystems involving yet unidentified vector, possibly from the genus Reptalus or unidentified weed. Moreover, a co- occurence of BN and FD phytoplasma in the same vineyard was identified. The genotyping of FD strains from both grapevine and Scaphoideus titanus has shown the presence of at least two distinct FD genotypes at two different locations, suggesting separate introductions of the disease in the country. Conclusions In this study, MLST proved to be a useful and informative tool allowing a step forward in better understanding of GY epidemiology in Croatia.

Izvorni jezik
Engleski

Znanstvena područja
Biologija

POVEZANOST RADA