Pest categorisation of the non-EU phytoplasmas of Cydonia Mill., Fragaria L., Malus Mill., Prunus L., Pyrus L., Ribes L., Rubus L. and Vitis L

History and Current Status of Phytoplasma Diseases in the Middle East

Phytoplasmas that are associated with fruit crops, vegetables, cereal and oilseed crops, trees, ornamental, and weeds are increasing at an alarming rate in the Middle East. Up to now, fourteen 16Sr groups of phytoplasma have been identified in association with more than 164 plant species in this region. Peanut witches' broom phytoplasma strains (16SrII) are the prevalent group, especially in the south of Iran and Gulf states, and have been found to be associated with 81 host plant species. In addition, phytoplasmas belonging to the 16SrVI, 16SrIX, and 16SrXII groups have been frequently reported from a wide range of crops. On the other hand, phytoplasmas belonging to 16SrIV, 16SrV, 16SrX, 16SrXI, 16SrXIV, and 16SrXXIX groups have limited geographical distribution and host range. Twenty-two insect vectors have been reported as putative phytoplasma vectors in the Middle East, of which Orosius albicinctus can transmit diverse phytoplasma strains. Almond witches' broom, tomato big bud, lime witches' broom, and alfalfa witches' broom are known as the most destructive diseases. The review summarizes phytoplasma diseases in the Middle East, with specific emphasis on the occurrence, host range, and transmission of the most common phytoplasma groups.

List of non-EU phytoplasmas of tuber-forming Solanum spp

Following a request from the European Commission, the EFSA Panel on Plant Health prepared a list of non-EU phytoplasmas of tuber-forming Solanum spp. A systematic literature review and search of databases identified 12 phytoplasmas infecting S. tuberosum. These phytoplasmas were assigned to three categories. The first group (a) consists of seven non-EU phytoplasmas, known to occur only outside the EU ('Candidatus Phytoplasma americanum', 'Ca. P. australiense', 'Ca. P. fragariae'-related strain (YN-169, YN-10G) and 'Ca. P. hispanicum') or having only limited presence in the EU ('Ca. P. aurantifolia'-related strains, 'Ca. P. pruni'-related strains and 'Ca. P. trifolii'). The second group (b) consists of three phytoplasmas originally described or reported from the EU. The third group (c) consists of two phytoplasmas with substantial presence in the EU, whose presence in S. tuberosum is not fully supported by the available literature. Phytoplasmas of categories (b) and (c) were excluded at this stage from further categorisation efforts. Three phytoplasmas from category (a) ('Ca. P. australiense', 'Ca. P. hispanicum' and 'Ca. P. trifolii') were excluded from further categorisation, as a pest categorisation has already been performed by EFSA. Comments provided by the EU Member States were integrated in the opinion. The main uncertainties of this listing concern: the taxonomy, the geographic distribution and prevalence and host range. The following phytoplasmas considered as non-EU and whose presence in S. tuberosum is fully supported by literature (category (a)) are categorised by the Panel in a separate opinion: 'Ca. P. americanum', 'Ca. P. fragariae'-related strain (YN-169, YN-10G), 'Ca. P. aurantifolia'-related strains and 'Ca. P. pruni'-related strains.

Pest categorisation of the non-EU phytoplasmas of tuber-forming Solanum spp

Following a request from the European Commission, the EFSA Panel on Plant Health performed a pest categorisation of four phytoplasmas of tuber-forming Solanum spp. known to occur only outside the EU or having a limited presence in the EU. The only tuber-forming species of Solanum reported to be phytoplasma infected is S. tuberosum. This opinion covers 'Candidatus Phytoplasma americanum', 'Ca. P. aurantifolia'-related strains (GD32; St_JO_10, 14, 17; PPT-SA; Rus-343F; PPT-GTO29, -GTO30, -SINTV; Potato Huayao Survey 2; Potato hair sprouts), 'Ca. P. fragariae'-related strains (YN-169, YN-10G) and 'Ca. P. pruni'-related strains (Clover yellow edge; Potato purple top AKpot7, MT117, AKpot6; PPT-COAHP, -GTOP). Phytoplasmas can be detected by molecular methods and are efficiently transmitted by vegetative propagation. Phytoplasmas are also transmitted in a persistent and propagative manner by some insects belonging to families within Cicadomorpha, Fulgoromorpha and Sternorrhyncha (order Hemiptera). No transovarial, pollen or seed transmission has been reported. The reported natural host range of the phytoplasmas categorised here varies from restricted ('Ca. P. americanum', and 'Ca. P. fragariae'-related strains) to wide ('Ca. P. aurantifolia'-related strains and 'Ca. P. pruni'-related strains), thus increasing the possible entry pathways in the latter case. S. tuberosum is widely cultivated in the EU. All the categorised phytoplasmas can enter and spread through the trade of host plants for planting, and by vectors. Establishment of these phytoplasmas is not expected to be limited by EU environmental conditions. The introduction of these phytoplasmas in the EU would have an economic impact. There are measures to reduce the risk of entry, establishment, spread and impact. Uncertainties result from limited information on distribution, biology and epidemiology. All the phytoplasmas categorised here meet the criteria evaluated by EFSA to qualify as potential Union quarantine pests, and they do not meet all the criteria to qualify as potential regulated non-quarantine pests, because they do not occur or are not known to be widespread in the EU.