Phytoplasmas Associated with Grapevine Yellows Disease in Chile

Abstract

An extensive survey was performed from 2002 to 2006 to detect and identify phytoplasmas associated with Chilean grapevines. Nested polymerase chain reaction assays using phytoplasma universal primer pairs P1/P7 and R16F2n/R2 detected phytoplasmas in 34 out of the 94 samples tested (36%). Restriction fragment length polymorphism (RFLP) analyses, cloning, and sequencing allowed identification of phytoplasmas belonging to ribosomal subgroups 16SrI-B, 16SrI-C, 16SrVII-A, and 16SrXII-A. The 16SrVII-A phytoplasma represents a new finding in grapevine; moreover, variability of the RFLP profile was observed in some of the 16SrXII-A phytoplasmas, indicating possible new ribosomal subgroups. Mixed phytoplasma infections and infections of phytoplasmas together with one or more viruses also occurred.

The underestimated diversity of phytoplasmas in Latin America

“…AY741531). This strain, previously classified as 16SrVII-A (Gajardo et al, 2009), showed a maximum similarity coefficient of only 0.94 with the reference pattern of subgroup 16SrVII-A (GenBank accession no. AF092209) (see the supplementary information).…”

“…In Latin America, members of group 16SrXII have been detected in only two countries (Chile and Bolivia), associated with grapevine and peach, respectively Gajardo et al, 2009). In this study, we identified the Isidro peach phytoplasma (GenBank accession no.…”

“…One remarkable phenomenon that we observed during this study was the preferential distribution of certain phytoplasma groups in the southern or northern hemisphere (Table 1). For example, members of the 16SrII groups have been detected in Argentina or Chile, the most southerly countries in Latin America, while members of the 16SrI group were not detected until after 2000 in those countries located in the southern hemisphere Gajardo et al, 2009). On the other hand, the detection of group 16SrVII phytoplasmas has hitherto been restricted to the southern hemisphere countries Brazil, Chile and Argentina (Table 1).…”

Phytoplasmas and Phytoplasma Diseases: A Severe Threat to Agriculture

“…In this case the disease management is very difficult since both phytoplasma and insect vectors are non-host specific, however, the usefulness of tuf gene polymorphism for rapid and cheap phytoplasma detection in epidemiological studies of BN was clearly shown [47] [48]. GY diseases occur in other areas of the world where affected plants exhibit syndromes that are seemingly indistinguishable from those of FD or BN but are associated with different phytoplasmas such as aster yellows (16SrI-B) in Italy and South Africa [49] [50], ash yellows (16SrVII-A) in Chile [51], and Australian grapevine yellows in Australia (16SrXII-B) [52] therefore specific local studies are necessary to devise the best management after identification of the insect vector.…”

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

“…On the other hand, 'Ca. P. fraxini' was reported associated with GY only in some regions of Chile (Gajardo et al, 2009) and it is reported to affect ornamental tree and shrubs and also in alfalfa in the American continent (Conci et al, 2005;Franco-Lara & Henao, 2014;Griffiths, Sinclair, Smart, & Davis, 1999;Sinclair, Griffiths, & Davis, 1996). Therefore, its presence in grapevine is of great phytosanitary significance due to its commercial interest and represents a potential threat for disease spread to other crops and landscape trees in Iran.…”