Evaluation continues

Candidate

Candidatus Phytoplasma solani' (CPs) is transmitted by grafting and vegetative propagation of infected hosts, and by several insect vector species (EU COM, 2016). With the exception of lavender (and maize), most crops affected by CPs are dead-end hosts as they are not hosts for the insect vectors. However weed species can act as a reservoir (EFSA, 2014). Plants for planting are the main pathway in areas where vectors are not present and may pose an entry risk for the nymphal stages of vector.

Yes

CPs has a high impact on lavender crops. After displaying early symptoms, characterised by low vigour and leaf yellowing, the canopy of infected lavender dries by sectors and plants eventually die. Because of epidemic propagation by H. obsoletus, able to complete its life cycle on this crop, fields of L. angustifolia are usually destroyed within 4–5 years in south-eastern France. Hybrids between L. angustifolia and L. latifolia, previously considered to be tolerant, exhibit the same symptoms and can reach an equivalent level of infection (EFSA-PLH, 2014). In a report from France, the disease incidence in lavender fields ranged from 1% to 68% at spring time and increased from 17% to 99% during fall, while at the same time the mean disease severity also increased significantly (Danet et al., 2010). Between 2006 and 2010 some French regions lost almost half of the harvest, and a significant part of the areas was uprooted (Grebenicharski, 2016).

Major

No

Candidate

candidate

Evaluation continues

Candidate

Lavender may be grown for ornamental purposes. 'Candidatus Phytoplasma solani' (CPs) is transmitted by grafting and vegetative propagation of infected hosts, and by several insect vector species (EU COM, 2016). With the exception of lavender (and maize), most crops affected by CPs are dead-end hosts as they are not hosts for the insect vectors. However weed species can act as a reservoir (EFSA, 2014). Plants for planting are also the main pathway in areas where vectors are not present and may pose an entry risk for the nymphal stages of vector. Plants for planting of lavender are also a pathway for crops intended to be grown in protected conditions.

Yes

CPs has a high impact on lavender crops. After displaying early symptoms, characterised by low vigour and leaf yellowing, the canopy of infected lavender dries by sectors and plants eventually die. Because of epidemic propagation by H. obsoletus, able to complete its life cycle on this crop, fields of L. angustifolia are usually destroyed within 4–5 years in south-eastern France. Hybrids between L. angustifolia and L. latifolia, previously considered to be tolerant, exhibit the same symptoms and can reach an equivalent level of infection (EFSA-PLH, 2014). In a report from France, the disease incidence in lavender fields ranged from 1% to 68% at spring time and increased from 17% to 99% during fall, while at the same time the mean disease severity also increased significantly (Danet et al., 2010). Between 2006 and 2010 some French regions lost almost half of the harvest, and a significant part of the areas was uprooted (Grebenicharski, 2016).

Major

No

Candidate

candidate

Evaluation continues

Candidate

Candidatus Phytoplasma solani' (CPs) is transmitted by grafting and vegetative propagation of infected hosts, and by several insect vector species (EU COM, 2016). With the exception of lavender and maize, most crops affected by CPs are dead-end hosts as they are not hosts for the insect vectors. However, weed species can act as a reservoir (EFSA-PLH, 2014). In Germany the organism was for example found in potatoes in two consecutive years in the same area and the suspected source was infected weeds in the surroundings (EPPO Reporting Service 2008/213; 2010/155). As a consequence, natural spread from the reservoir of infected weed species is the main pathway of spread to actively growing crops in areas where the organism is present. CPs is not thought to be transmitted in the true seed of any of its hosts (EPPO, Data Sheets on Quarantine Pest), so vegetable propagating and planting material can only become a pathway in the limited timeframe between sowing and transplantation of the propagating and planting material. Regarding vegetable Solanaceae, it has been found in tomato, pepper, and aubergine (EFSA-PLH, 2014). Most young plants of vegetable Solanaceae are usually grown in protected conditions where the vector is absent and weeds can be controlled. Given that the major agricultural Solanaceous crops are dead-end-hosts, the only potential economic impact arises from the negative effects of CPs on the infected transplants themselves. Furthermore, it is not clear whether vectors spread CPs within economic host crops to any extent. In fact, in nature, the economically important host crops are not important for the continuity of the virus; an incomparably greater role is played by such wild plants as Convolvulus arvensis , clovers and, probably, Asteraceae and other plants (EPPO, Data Sheets on Quarantine Pest).
The vegetable SEWG concluded that plant for planting is only a significant pathway in relation to plants grown under protected conditions, when the vector can be excluded.

Yes

Severe impact of CP on plant growth, fruit yield and quality is recorded for infected tomato, eggplant and pepper plants (Fialova et al., 2009; Navràtil et al., 2009; Marchoux and Rougier, 1987). In severe epidemics, yield losses as high as 60 % in tomato and 93 % in pepper have been reported (EFSA-PLH, 2014).

Medium

No

Candidate

Impact is considerate moderate to minor, fluctuating and depending on climate, presence of weed inoculum sources and vector populations. Impact is strongly affected by natural spread (EFSA-PLH, 2014).

candidate

Yes, for plants grown under protective conditions: For young plants raised under protected conditions, it may be possible to keep the plants free of the pest. For any plants grown outside, there will be no practical measures to prevent infections by vectors, which are both very good fliers and difficult to tackle by insecticide suppression. Young plants of fruit vegetables that are grown under protected conditions (tomato, pepper, eggplant) are usually grown in glasshouses that have insect screens in the windows (situation in the Netherlands), but not during the part of the season (hot dry summers) which stimulate vector migration. Measures to avoid unacceptable economic impact on vegetable propagating and planting material therefore seem somewhat redundant.

Evaluation continues

Candidatus Phytoplasma solani' is only listed in one EPPO PM 4 Standard on ornamental solanaceae: PM 4/26 Pathogen-tested material of Petunia. Evaluation continues for other solanaceae.

Candidate

Candidatus Phytoplasma solani' (CPs) is transmitted by grafting and vegetative propagation of infected hosts, and by several insect vector species (EU COM, 2016). With the exception of lavender and maize, most crops affected by CPs are dead-end hosts as they are not hosts for the insect vectors. However weed species can act as a reservoir (EFSA, 2014). Moreover presence of the vectors varies in different parts of the region (plants for planting are also the main pathway in area where vectors are not present).
Regarding potential ornamental Solanaceae, it has been found in pepper, aubergine, Solanum nigrum and Datura stramonium (EFSA 2014), though it is not known if some types of these are widely grown as ornamental plants. In January 2012, it was isolated from 'trailing' Petunia hybrida plants, causing an abnormal growth habit of sprouting unusual multiple plantlets from the lateral buds (Chung et al., 2013). Most young plants of ornamental Solanaceae are usually grown in protected conditions where the vector is absent and weeds can be controlled.
In conclusion, plants for planting of ornamental Solanaceae are a pathway, and can be considered a significant pathway for crops intended to be grown continuously in protected conditions. They would not be considered as a significant pathway in outside areas where the pathogen (and therefore also the vector) is present, because the presence of vectors will transmit the pathogen to plants transplanted into the field. Most ornamental Solanaceae (such as petunia) are usually transplanted outside in gardens etc. as young plants.

Yes

Petunia has been shown to be impacted (Chung et al 2013) but no other references are available for ornamental Solanaceae.
Remark: NL and AIPH considered the economic impact on solanaceous ornamentals as acceptable. The only impacted solanaceous species is considered to be Petunia (Chung et al., 2013). NL and AIPH added that solanaceous ornamentals are usually grown in greenhouses (where weeds that may act as reservoirs of the organism are usually absent) or can easily be controlled.

Minor

Yes

Yes

Candidate

Petunia has been shown to be impacted (Chung et al 2013) but no other references are available for ornamental Solanaceae. However, there is a risk for the other economically important host plants growing in the same place of production. This risk is considered to be very limited if the material is 'substantially free from' the pest.

candidate

Risk management measures are included in the EFSA opinion (EFSA, 2014).

Evaluation continues

In EPPO PM 4/28 Standard the crop should be free from Potato stolbur phytoplasma. However, because of the NL comment concerning the main pathway, further analysis was carried out by the SEWG on the pathway question.

Candidate

Candidatus Phytoplasma solani' (CPs) is transmitted by grafting and vegetative propagation of infected hosts, and by several insect vector species (EU COM, 2016). With the exception of lavender and maize, most crops affected by CPs are dead-end hosts as they are not hosts for the insect vectors. However weed species can act as a reservoir (EFSA, 2014). In Germany the organism was for example found in potatoes in two consecutive years in the same area and the suspected source was infected weeds in the surroundings (EPPO Reporting Service 2008/213; 2010/155). As a consequence, natural spread from the reservoir of infected weed species is the main pathway of spread to actively growing crops in areas where the organism is present. However economic impact arises at the start of the growing season, because most infected seed potatoes do not grow (‘effect on the intended use’). Up to that point, the plants for planting are considered to be the main (indeed only) pathway. Moreover presence of the vectors varies in different parts of the region (plants for planting are also the main pathway in area where vectors are not present).