Identification of a 16SrII-E Phytoplasma in Calendula arvensis, Solanum nigrum, and Chenopodium spp.

Abstract

Epidemiological surveys were performed in Northern Sardinia (Italy) in a 10-year-old vineyard affected by “Bois noir” disease. Samples collected between May and October 2003 from chlorotic and stunted weeds belonging to 14 different taxonomic groups were indexed molecularly for detection of phytoplasmas. Nested polymerase chain reaction (PCR) assays using primers specific for the phytoplasma 16SrDNA gene showed three of six Calendula arvensis, one of two Solanum nigrum, and one of seven Chenopodium spp. assayed positive. Restriction fragment length polymorphism analyses and sequencing of amplified 16SrDNA fragments identified a putative phytoplasma in the ribosomal subgroup 16SrII-E. Further characterization of the rps3 gene, coding a ribosomal protein, confirmed the identification. However, the weeds and leafhop-per species collected in the vineyard tested negative by PCR assays for the Stolbur phytoplasma, the causal agent of “Bois noir”. This is the first report of a phytoplasma of the 16SrII-E subgroup infecting C. arvensis, S. nigrum, and Chenopodium spp.

Molecular identification of diverse ‘Candidatus Phytoplasma’ species associated with grapevine decline in Iran

“…The methodology applied allows phytoplasma detection in a high number of grapevine symptomatic samples but not in all of them; moreover, the nested PCR resulted necessary in order to achieve detection very likely due to the uneven distribution and low concentration of the pathogen under Iranian conditions. The primers R16F2n/R2 and R16(I)F1/R1 were those allowing the phytoplasma classification at the ribosomal subgroup level (Lee, Gundersen‐Rindal, Davis, & Bartoszyk, ; Tolu et al., ), while the primers M1/M2 were useful for their sensitive detection ability.…”

“…The extracted nucleic acid (20-80 ng) was used for polymerase chain reaction (PCR) amplification with universal phytoplasma primers P1/Tint (Deng & Hiruki, 1991;Smart et al, 1996) followed by R16F2n/R2, R16mF1/mR1 (Gundersen & Lee, 1996), R16(I)F1/R1 (Lee, Gundersen, Hammond, & Davis, 1994) or 6R758f/16R1232r (=M1/M2) primers (Gibb, Padovan, & Mogen, 1995) in nested-PCR assays using as template the PCR products diluted with sterile distilled water (1:30). In particular in nested PCR with R16F2n/R2 primers were used to determine by RFLP analyses the phytoplasma ribosomal group, while the use of R16(I)F1/R1 primers amplifying phytoplasmas in 16SrI, 16SrII, 16SrXII groups (Tolu et al, 2006) allowed to determine subgroups ( Table 1). The use of nested PCR with M1/M2 primers amplifying about 500 bp from all phytoplasmas was adopted to increase the detection system sensitivity.…”

“…; P, marker phiX174 HaeIII digested with fragment sizes in base pairs from top to bottom of 1,353; 1,078; 872; 603; 310; 281; 271; 234; 194; 118 and 72 nested PCR resulted necessary in order to achieve detection very likely due to the uneven distribution and low concentration of the pathogen under Iranian conditions. The primers R16F2n/ R2 and R16(I)F1/R1 were those allowing the phytoplasma classification at the ribosomal subgroup level(Lee, Gundersen-Rindal, Davis, & Bartoszyk, 1998;Tolu et al, 2006), while the primers M1/M2 were useful for their sensitive detection ability.Diseases associated with the presence of phytoplasmas in grapevine were only recently detected in Iran, when 'Ca. P. solani'-related (16SrXII-A, "stolbur") and 16SrIX-C ('Ca.…”

Molecular study of phytoplasmas associated with pistachio yellows in Iran

“…The primers R16F2n/R2 and R16(I)F1/R1 allowed phytoplasma classification at the ribosomal subgroup level (Lee et al., ; Tolu et al. ).…”

Identification and characterization of a phytoplasma disease of jute (Corchorus olitorius L.) from south-western Turkey

“…8). Geographical distribution of 16SrII group phytoplasmas was mainly located in Asia, Africa and Australia (Lee et al, 2000;Fossiac and Wilson, 2009) and more recently they were reported from Southern Europe (Tolu et al, 2006;Mitrovi c et al, 2012) and Cuba (Arocha et al, 2009). Recently, the 16SrII-D group phytoplasmas were detected from sesame phyllody infected plants and the potential vector Orosius orientalis (Matsumura) both from an experimental sesame field at the Akdeniz University campus and other commercial sesame growing areas in Antalya, Turkey ( € Ozdemir et al, 2013( € Ozdemir et al, , 2014.…”