Naslov
Molecular variability of Aster Yellows phytoplasmas infecting Lombardy poplar tree population in the urban Zagreb area

Autori
Škorić, Dijana ; Šeruga Musić, Martina ; Novokmet, Mislav ; Botti, Simona ; Bertaccini, Assunta

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

Izvornik
Book of Abstracts of the 16th Congress of the International Organization for Mycoplasmology (IOM) / Ayling, Roger D. ; Citti, Cristine ; Nicholas, Robin A. - Cambridge : IOM, 2006

Skup
16th Congress of the International Organization for Mycoplasmology (IOM)

Mjesto i datum
Cambridge, Ujedinjeno Kraljevstvo, 09.07.2006. - 14.07.2006

Vrsta sudjelovanja
Poster

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
Aster Yellows; molecular variability; phytoplasma; poplar; Zagreb

Sažetak
In previous studies, Aster Yellows (AY) phytoplasmas were identified in Populus nigra L. ‘ Italica’ (Lombardy poplar) trees from the urban area of Zagreb. This pathogen was classified as a member of a newly described ribosomal subgroup 16SrI-P and ribosomal protein (rp) subgroup rp-O. The aim of this research was to examine the incidence and molecular variability of phytoplasmas in Lombardy poplar tree population of wider Zagreb urban area. Total nucleic acid was extracted from leaf and branch samples of 34 symptomatic and asymptomatic trees by using 3% CTAB extraction procedure. Phytoplasma 16S rDNA was amplified in direct PCR by using R16F1/R0 and/or P1/P7 universal phytoplasma primer pairs. Nested PCR reactions were primed by R16F2n/R2, 16R738f/R1232r, as well as group-specific R16(I)F1/R1 oligonucleotides. A major portion of the elongation factor EF-Tu gene, ribosomal protein L22 gene, and the region encoding putative aa kinase and ribosomal recycling factor were also amplified by using primers fTufu/rTufu, rpF1/R1, and BB88F1/R1, respectively, and followed by RFLP analyses. Phytoplasmas with restriction profiles referable to AY were detected in 12 samples. PCR/RFLP analyses of 16S rRNA and of other conserved phytoplasma gene regions revealed that amplicons from 10 positive samples had profiles identical to the phytoplasma belonging to the ribosomal 16SrI-P and rp-O subgroup. In the remaining 2 positive samples, amplicons obtained with rpF1/rpR1, fTufu/rTufu and BB88/F1/R1 primers, had unique, previously unrecorded, RFLP profiles. In order to analyze these two phytoplasmas in more detail and to infer phylogenetic relationships, their 16S rRNA and spacer regions were amplified, analyzed by RFLP, cloned and sequenced. Virtual RFLP analyses were also performed on the obtained sequences. Comparisons with the 16SrI-P phytoplasma profiles revealed differential restriction sites confirming the presence of molecular variability within their 16S and the spacer regions. Positions of these sequences in the phylogenetic tree reflected the molecular variability found in the 16S region.

Izvorni jezik
Engleski

Znanstvena područja
Biologija

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