RESUMO
Despite the importance of storage root (SR) organs for cassava and the other root crops yield, their developmental origin is poorly understood. Here we use multiple approaches to shed light on the initial stages of root development demonstrating that SR and fibrous roots (FR) follow different rhizogenic processes. Transcriptome analysis carried out on roots collected before, during and after root bulking highlighted early and specific activation of a number of functions essential for root swelling and identified root-specific genes able to effectively discriminate emerging FR and SR. Starch and sugars start to accumulate at a higher rate in SR before they swell but only after parenchyma tissue has been produced. Finally, using non-destructive computed tomography measurements, we show that SR (but not FR) contain, since their emergence from the stem, an inner channel structure in continuity with the stem secondary xylem, indicating that SR derive from a distinct rhizogenic process compared with FR.
Assuntos
Manihot , Regulação da Expressão Gênica de Plantas , Manihot/genética , Raízes de Plantas , Amido , XilemaRESUMO
Cassava storage roots are among the most important root crops worldwide, and represent one of the most consumed staple foods in sub-Saharan Africa. The vegetatively propagated tropical shrub can form many starchy tuberous roots from its stem. These storage roots are formed through the activation of secondary root growth processes. However, the underlying genetic regulation of storage root development is largely unknown. Here we report distinct structural and transcriptional changes occurring during the early phases of storage root development. A pronounced increase in auxin-related transcripts and the transcriptional activation of secondary growth factors, as well as a decrease in gibberellin-related transcripts were observed during the early stages of secondary root growth. This was accompanied by increased cell wall biosynthesis, most notably increased during the initial xylem expansion within the root vasculature. Starch storage metabolism was activated only after the formation of the vascular cambium. The formation of non-lignified xylem parenchyma cells and the activation of starch storage metabolism coincided with increased expression of the KNOX/BEL genes KNAT1, PENNYWISE, and POUND-FOOLISH, indicating their importance for proper xylem parenchyma function.
Assuntos
Câmbio , Manihot , Câmbio/genética , Câmbio/metabolismo , Regulação da Expressão Gênica de Plantas , Ácidos Indolacéticos , Manihot/genética , Manihot/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/metabolismoRESUMO
RNA silencing plays a critical role in plant resistance against viruses. To counteract host defense, plant viruses encode viral suppressors of RNA silencing (VSRs) that interfere with the cellular silencing machinery through various mechanisms not always well understood. We examined the role of Mungbean yellow mosaic virus (MYMV) AC4 and showed that it is essential for infectivity but not for virus replication. It acts as a determinant of pathogenicity and counteracts virus induced gene silencing by strongly suppressing the systemic phase of silencing whereas it does not interfere with local production of siRNA. We demonstrate the ability of AC4 to bind native 21-25 nt siRNAs in vitro by electrophoretic mobility shift assay. While most of the known VSRs have cytoplasmic localization, we observed that despite its hydrophilic nature and the absence of trans-membrane domain, MYMV AC4 specifically accumulates to the plasma membrane (PM). We show that AC4 binds to PM via S-palmitoylation, a process of post-translational modification regulating membrane-protein interactions, not known for plant viral protein before. When localized to the PM, AC4 strongly suppresses systemic silencing whereas its delocalization impairs VSR activity of the protein. We also show that AC4 interacts with the receptor-like kinase (RLK) BARELY ANY MERISTEM 1 (BAM1), a positive regulator of the cell-to-cell movement of RNAi. The absolute requirement of PM localization for direct silencing suppression activity of AC4 is novel and intriguing. We discuss a possible model of action: palmitoylated AC4 anchors to the PM by means of palmitate to acquire the optimal conformation to bind siRNAs, hinder their systemic movement and hence suppress the spread of the PTGS signal in the plant.
Assuntos
Begomovirus/fisiologia , Membrana Celular/metabolismo , Regulação Viral da Expressão Gênica/fisiologia , Interferência de RNA/fisiologia , Proteínas Virais/metabolismo , Acilação , Begomovirus/patogenicidade , Lipoilação , Transporte Proteico/fisiologiaRESUMO
The transport of a viral genome from cell to cell is enabled by movement proteins (MPs) targeting the cell periphery to mediate the gating of plasmodesmata. Given their essential role in the development of viral infection, understanding the regulation of MPs is of great importance. Here, we show that cauliflower mosaic virus (CaMV) MP contains three tyrosine-based sorting signals that interact with an Arabidopsis (Arabidopsis thaliana) µA-adaptin subunit. Fluorophore-tagged MP is incorporated into vesicles labeled with the endocytic tracer N-(3-triethylammoniumpropyl)-4-(6-(4-(diethylamino)phenyl)hexatrienyl)pyridinium dibromide. The presence of at least one of the three endocytosis motifs is essential for internalization of the protein from the plasma membrane to early endosomes, for tubule formation, and for CaMV infection. In addition, we show that MP colocalizes in vesicles with the Rab GTPase AtRAB-F2b, which is resident in prevacuolar late endosomal compartments that deliver proteins to the vacuole for degradation. Altogether, these results demonstrate that CaMV MP traffics in the endocytic pathway and that virus viability depends on functional host endomembranes.
Assuntos
Caulimovirus/metabolismo , Endossomos/metabolismo , Membranas Intracelulares/metabolismo , Proteínas do Movimento Viral em Plantas/metabolismo , Vesículas Transportadoras/metabolismo , Subunidades mu do Complexo de Proteínas Adaptadoras/metabolismo , Motivos de Aminoácidos , Sequência de Aminoácidos , Arabidopsis/efeitos dos fármacos , Arabidopsis/metabolismo , Arabidopsis/virologia , Brassica rapa/efeitos dos fármacos , Brassica rapa/virologia , Brefeldina A/farmacologia , Caulimovirus/efeitos dos fármacos , Caulimovirus/patogenicidade , Compartimento Celular/efeitos dos fármacos , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Endocitose/efeitos dos fármacos , Endossomos/efeitos dos fármacos , Proteínas de Fluorescência Verde/metabolismo , Membranas Intracelulares/efeitos dos fármacos , Modelos Biológicos , Dados de Sequência Molecular , Mutação/genética , Proteínas de Plantas/efeitos dos fármacos , Proteínas de Plantas/metabolismo , Proteínas do Movimento Viral em Plantas/química , Ligação Proteica/efeitos dos fármacos , Transporte Proteico/efeitos dos fármacos , Protoplastos/efeitos dos fármacos , Protoplastos/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Relação Estrutura-Atividade , Nicotiana/metabolismo , Vesículas Transportadoras/efeitos dos fármacos , Tirosina/metabolismo , Tirfostinas/farmacologiaRESUMO
The European Commission requested the EFSA Panel on Plant Health to prepare and deliver risk assessments for commodities listed in Commission Implementing Regulation (EU) 2018/2019 as 'High risk plants, plant products and other objects'. This Scientific Opinion covers plant health risks posed by plants of Prunus avium possibly grafted on rootstocks of either P. avium, P. canescens, P. cerasus, P. pseudocerasus or their hybrids imported from the UK, taking into account the available scientific information, including the technical information provided by the UK. All pests associated with the commodities were evaluated against specific criteria for their relevance for this opinion. Three quarantine pests Scirtothrips dorsalis, tobacco ringspot virus and tomato ringspot virus), one protected zone EU quarantine pest (Bemisia tabaci (European population), and three non- regulated pests (Colletotrichum aenigma, Eulecanium excrescens and Takahashia japonica) that fulfilled all relevant criteria were selected for further evaluation. The risk mitigation measures proposed in the technical Dossier from the UK were evaluated, taking into account the possible limiting factors. For these pests, expert judgement is given on the likelihood of pest freedom, taking into consideration the risk mitigation measures acting on the pest, including uncertainties associated with the assessment. The degree of pest freedom varies among the pests evaluated, with Colletotrichum aenigma being the pest most frequently expected on the imported potted plants. The Expert Knowledge Elicitation indicated with 95% certainty that between 9971 and 10,000 plants per 10,000 would be free from the above-mentioned fungus.
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The European Commission requested the EFSA Panel on Plant Health to prepare and deliver risk assessments for commodities listed in Commission Implementing Regulation (EU) 2018/2019 as 'High-risk plants, plant products and other objects'. This Scientific Opinion covers plant health risks posed by defoliated 1- or 2-year old bare root plants for planting (grafted or not) of 12 Prunus species (Prunus armeniaca, P. avium, P. canescens, P. cerasifera, P. cerasus, P. davidiana, P. domestica, P. dulcis, P. fontanesiana, P. persica, P. salicina, P. tomentosa) imported from Moldova, taking into account the available scientific information, including the technical information provided by the applicant country. The evaluation identified three EU-quarantine pests, Erwinia amylovora (protected zone quarantine pest), Xiphinema rivesi non-EU populations and Xanthomonas arboricola pv. pruni (protected zone quarantine pest), which were selected for further evaluation, based on defined criteria, including their presence in the applicant country. It should be noted that there is uncertainty regarding whether all relevant pests have been identified due to a limited number of scientific publications and pest surveys in Moldova. For the three selected pests, the risk mitigation measures proposed in the technical dossier from Moldova were evaluated taking into account the possible limiting factors. For these pests, an expert judgement is given on the likelihood of pest freedom taking into consideration the risk mitigation measures acting on it, including uncertainties associated with the assessment. The degree of pest freedom varies among the pests evaluated, with Erwinia amylovora being the pest most frequently expected on the imported plants. The Expert Knowledge Elicitation indicated, with 95% certainty, that between 9823 and 10,000 bundles (comprising 10-20 plants per bundle) out of 10,000 bundles would be free from E. amylovora.
RESUMO
The European Commission requested the EFSA Panel on Plant Health to prepare and deliver risk assessments for commodities listed in Commission Implementing Regulation (EU) 2018/2019 as 'High risk plants, plant products and other objects'. This Scientific Opinion covers plant health risks posed by potted plants and bundles of bare-root plants or cell grown young plants or graftwood/budwood of Prunus spinosa imported from the United Kingdom, taking into account the available scientific information, including the technical information provided by the UK. All pests associated with the commodities were evaluated against specific criteria for their relevance for this opinion. One quarantine pest, Scirtothrips dorsalis, one protected zone quarantine pest Bemisia tabaci (European population) and one non-regulated pest, the scale Eulecanium excrescens, that fulfilled all relevant criteria were selected for further evaluation. The risk mitigation measures proposed in the technical Dossier from the UK were evaluated, taking into account the possible limiting factors. For these pests, expert judgement is given on the likelihood of pest freedom, taking into consideration the risk mitigation measures acting on the pest, including uncertainties associated with the assessment. The degree of pest freedom varies among the pests evaluated, with E. excrescens being the pest most frequently expected on the imported potted plants. The Expert Knowledge Elicitation indicated with 95% certainty that between 9981 and 10,000 plants per 10,000 would be free from the above-mentioned scale.
RESUMO
Striga hermonthica is the most widespread and destructive plant parasite infesting maize and other major crops in sub-Saharan Africa where it causes severe yield losses and threatens food security. Several tolerant maize lines supporting reduced S. hermonthica emergence have been deployed. However, the molecular bases of such resistance are yet poorly understood. Based on a time course comparative gene expression analysis between susceptible and resistant maize lines we have confirmed resistance mechanisms known to be activated upon plant parasite infestation and identified potential novel players worth further investigation e.g. iron homeostasis and mitochondrial respiration-related genes. Most intriguingly, we show a previously unknown strategy of maize post-attachment resistance based on DIMBOA accumulation in S. hermonthica-infested maize roots. S. hermonthica infestation triggers positive regulation of gene expression in the hydroxamic acid (HA) pathway culminating with an accumulation of benzoxazinoids (BX), known for their antifeedant, insecticidal, antimicrobial, and allelopathic activities. We demonstrate that HA root content is positively correlated with S. hermonthica resistance in the resistant parent and its progenies and in unrelated maize lines. Downregulation of HA genes causes increased susceptibility to S. hermonthica infestation in loss-of-function maize mutants. While the mechanism of BX action in parasitic plant resistance is yet to be uncovered, the potential of this discovery for developing effective control and breeding strategies is enormous.
Assuntos
Striga , Striga/genética , Zea mays/genética , Melhoramento Vegetal , Produtos Agrícolas , Regulação para BaixoRESUMO
The EFSA Panel on Plant Health conducted a pest categorisation of cowpea mosaic virus (CPMV) for the EU territory. The identity of CPMV, a member of the genus Comovirus (family Secoviridae), is established and detection and identification methods are available. The pathogen is not included in the Commission Implementing Regulation (EU) 2019/2072. It has been reported from the Americas, and several countries in Africa and Asia and it is not known to be present in the EU in natural conditions. CPMV is considered a major pathogen of cowpea on which it causes symptoms ranging from mild to severe mosaic, chlorosis and necrosis. The virus has been reported sporadically on some other cultivated species of the family Fabaceae, including soybean and some common bean varieties. CPMV is transmitted by cowpea seeds, with uncertainty on the transmission rate. There is uncertainty on seed transmission by other Fabaceae host species due to lack of information. CPMV is also transmitted by several beetle species, one of which, Diabrotica virgifera virgifera, is present in the EU. Seeds for sowing of cowpea are identified as the major entry pathway. The cultivated area and production of cowpea in the EU territory are mainly limited to local varieties cultivated at a small scale in Mediterranean EU Member States. Should the pest establish in the EU, an impact is expected on cowpea crops at local scale. There is high uncertainty on the potential impact that CPMV would cause on other natural hosts cultivated in the EU due to the lack of information from the areas of CPMV's current distribution. Despite the uncertainty concerning the potential impact on bean and soybean crops in the EU, CPMV satisfies the criteria that are within the remit of EFSA to assess for it to be regarded as a potential Union quarantine pest.
RESUMO
The EFSA Panel on Plant Health updated its 2017 pest categorisation of coconut cadang cadang viroid (CCCVd) for the EU territory due to new data on its host range. The identity of CCCVd, a member of the genus Cocadviroid (family Pospiviroidae), is established and detection and identification methods are available. It is included as a quarantine pest for the EU in the Commission Implementing Regulation (EU) 2019/2072. CCCVd has been reported from the Philippines and Malaysia. It is not known to be present in the EU. The host range of CCCVd is restricted to Arecaceae species (palms), in particular, coconut palm (Cocos nucifera) to which it causes a lethal disease. Oil palm (Elaeis guineensis) and buri palm (Corypha utan) are other natural hosts of CCCVd. Palm species of several genera, including Phoenix spp. and other species grown and/or cultivated in the EU, have been identified as potential hosts. The viroid is naturally transmitted at low rate by seeds and pollen and possibly by additional not yet identified natural transmission means. It can be transmitted through vegetative propagation applied to some palm species. Plants for planting including seeds of its hosts have been identified as the main entry pathway of CCCVd. Potential hosts of CCCVd are present in the EU, therefore establishment is possible. Should the pest establish in the EU, an impact is expected, with uncertainty on its magnitude. The Panel identified the susceptibility of palm species grown in the EU as a key uncertainty potentially affecting the conclusion of this pest categorisation. Nevertheless, the pest satisfies the criteria that are within the remit of EFSA to assess for this viroid to be regarded as potential Union quarantine pest.
RESUMO
The European Commission requested the EFSA Panel on Plant Health to prepare and deliver risk assessments for commodities listed in Commission Implementing Regulation (EU) 2018/2019 as 'High risk plants, plant products and other objects'. This Scientific Opinion covers plant health risks posed by plants of Prunus persica and P. dulcis, as budwood/graftwood, rooted or grafted on rootstocks of either P. persica, P. dulcis, P. armeniaca, P. davidiana or their hybrids, imported from Türkiye, taking into account the available scientific information, including the technical information provided by Türkiye. All pests associated with the commodity were evaluated against specific criteria for their relevance for this opinion. Four quarantine pests (peach rosette mosaic virus, tomato ringspot virus, Anoplophora chinensis, Scirtothrips dorsalis) and 14 non-regulated pests (Hoplolaimus galeatus, Lasiodiplodia pseudotheobromae, Neoscytalidium dimidiatum, Neoscytalidium novaehollandiae, Didesmococcus unifasciatus, Euzophera semifuneralis, Lepidosaphes malicola, Lepidosaphes pistaciae, Maconellicoccus hirsutus, Malacosoma parallela, Nipaecoccus viridis, Phenacoccus solenopsis, Pochazia shantungensis, Russellaspis pustulans) that fulfilled all relevant criteria were selected for further evaluation. For these 18 pests, the risk mitigation measures proposed in the technical Dossier from Türkiye were evaluated taking into account the possible limiting factors. For the selected pests, an expert judgement is given on the likelihood of pest freedom taking into consideration the risk mitigation measures acting on the pest, including uncertainties associated with the assessment. The degree of pest freedom varies among the pests evaluated, with fungi from Botryosphaeriaceae family (L. pseudotheobromae, N. dimidiatum and N. novaehollandiae) being the pests most frequently expected on the imported plants. The Expert Knowledge Elicitation indicated with 95% certainty that between 9,813 and 10,000 bundles (consisting of 10 or 25 plants each) per 10,000 would be free from the above-mentioned fungi in the Botryosphaeriaceae family.
RESUMO
The European Commission requested the EFSA Panel on Plant Health to prepare and deliver risk assessments for commodities listed in Commission Implementing Regulation (EU) 2018/2019 as 'High-risk plants, plant products and other objects'. This Scientific Opinion covers plant health risks posed by bare root plants of Malus domestica grafted on rootstocks of either Malus domestica or Malus sylvestris imported from Bosnia and Herzegovina (BIH), taking into account the available scientific information, including the technical information provided by Bosnia and Herzegovina. All pests associated with the commodities were evaluated against specific criteria for their relevance for this opinion. One protected zone quarantine pest, Erwinia amylovora, fulfilled all relevant criteria and was selected for further evaluation. For E. amylovora, special requirements are specified in Commission Implementing Regulation (EU) 2019/2072. Based on the information provided in the Dossier, these specific requirements for E. amylovora are not met.
RESUMO
The European Commission requested the EFSA Panel on Plant Health to prepare and deliver risk assessments for commodities listed in Commission Implementing Regulation (EU) 2018/2019 as 'High risk plants, plant products and other objects'. This Scientific Opinion covers plant health risks posed by rooted plants and bundles of bare root plants or rooted cell grown young plants of Malus sylvestris imported from the UK, taking into account the available scientific information, including the technical information provided by the UK. All pests associated with the commodities were evaluated against specific criteria for their relevance for this opinion. Two quarantine pests (tobacco ringspot virus and tomato ringspot virus), one protected zone quarantine pest (Erwinia amylovora) and four non-regulated pests (Colletotrichum aenigma, Meloidogyne mali, Eulecanium excrescens and Takahashia japonica) that fulfilled all relevant criteria were selected for further evaluation. For Erwinia amylovora, special requirements are specified in Commission Implementing Regulation (EU) 2019/2072. Based on the information provided in the dossier, these specific requirements for E. amylovora are met. For the remaining six pests, the risk mitigation measures proposed in the technical Dossier from the UK were evaluated, taking into account the possible limiting factors. For these pests, expert judgement is given on the likelihood of pest freedom, taking into consideration the risk mitigation measures acting on the pest, including uncertainties associated with the assessment. The degree of pest freedom varies among the pests evaluated, with scales (Eulecanium excrescens and Takahashia japonica) being the pests most frequently expected on the imported bundles of bare root plants or rooted cell grown young plants. The expert knowledge elicitation indicated with 95% certainty that between 9,976 and 10,000 bundles (one bundle consisting of 5-15 plants for bare root plants or 25-50 plants for cell grown young plants) per 10,000 would be free from the above-mentioned scales.
RESUMO
The European Commission requested the EFSA Panel on Plant Health to prepare and deliver risk assessments for commodities listed in Commission Implementing Regulation (EU) 2018/2019 as 'High risk plants, plant products and other objects'. This Scientific Opinion covers plant health risks posed by rooted plants in pots, bundles of bare-rooted plants or trees and bundles of budwood and graftwood of Malus domestica imported from the United Kingdom, taking into account the available scientific information, including the technical information provided by the United Kingdom. All pests associated with the commodities were evaluated against specific criteria for their relevance for this opinion. Two quarantine pests (tobacco ringspot virus and tomato ringspot virus), one protected zone quarantine pest (Erwinia amylovora) and four non-regulated pests (Colletotrichum aenigma, Meloidogyne mali, Eulecanium excrescens, Takahashia japonica) that fulfilled all relevant criteria were selected for further evaluation. For E. amylovora, special requirements are specified in Commission Implementing Regulation (EU) 2019/2072. Based on the information provided in the Dossier, the specific requirements for E. amylovora were met. For the remaining six pests, the risk mitigation measures proposed in the technical Dossier from the UK were evaluated considering the possible limiting factors. For the selected pests, expert judgement is given on the likelihood of pest freedom, taking into consideration the risk mitigation measures acting on the pest, including uncertainties associated with the assessment. The degree of pest freedom varies among the pests evaluated, with scales (E. excrescens and T. japonica) being the pests most frequently expected on the imported budwood and graftwood. The Expert Knowledge Elicitation indicated with 95% certainty that between 9,976 and 10,000 bundles (consisting of 50 up to 500 plants each) per 10,000 would be free from the above-mentioned scales.
RESUMO
Superoxide dismutase (SOD) is a fundamental antioxidant enzyme that neutralises superoxide ions, one of the main reactive oxygen species (ROS). Extremophile organisms possess enzymes that offer high stability and catalytic performances under a wide range of conditions, thus representing an exceptional source of biocatalysts useful for industrial processes. In this study, SODs from the thermo-halophilic Aeropyrum pernix (SODAp) and the thermo-acidophilic Saccharolobus solfataricus (SODSs) were heterologously expressed in transgenic tomato cell cultures. Cell extracts enriched with SODAp and SODSs showed a remarkable resistance to salt and low pHs, respectively, together with optimal activity at high temperatures. Moreover, the treatment of tuna fillets with SODAp-extracts induced an extension of the shelf-life of this product without resorting to the use of illicit substances. The results suggested that the recombinant plant extracts enriched with the extremozymes could find potential applications as dietary supplements in the nutrition sector or as additives in the food preservation area, representing a more natural and appealing alternative to chemical preservatives for the market.
RESUMO
The European Commission requested the EFSA Panel on Plant Health to prepare and deliver risk assessments for commodities listed in Commission Implementing Regulation (EU) 2018/2019 as 'High risk plants, plant products and other objects'. This Scientific Opinion covers plant health risks posed by plants of Prunus domestica grafted on Prunus cerasifera imported from Ukraine, taking into account the available scientific information, including the technical information provided by Ukraine. All pests associated with the commodity were evaluated against specific criteria for their relevance for this opinion. One quarantine pest (Lopholeucaspis japonica), two protected zone quarantine pests (Erwinia amylovora and Xanthomonas arboricola pv. pruni) and one non-regulated pest (Eotetranychus prunicola) that fulfilled all relevant criteria were selected for further evaluation. For these four pests, the risk mitigation measures proposed in the technical dossier from Ukraine were evaluated taking into account the possible limiting factors. For the selected pests, an expert judgement is given on the likelihood of pest freedom taking into consideration the risk mitigation measures acting on the pest, including uncertainties associated with the assessment. The degree of pest freedom varies among the pests evaluated, with Xanthomonas arboricola pv. pruni being the pest most frequently expected on the imported plants. The Expert Knowledge Elicitation indicated with 95% certainty that between 9,870 and 10,000 bundles (consisting of 10 plants each) per 10,000 would be free from Xanthomonas arboricola pv. pruni.
RESUMO
The EFSA Panel on Plant Health conducted a pest categorisation of chickpea chlorotic dwarf virus (CpCDV) for the EU territory. The identity of CpCDV, a member of the genus Mastrevirus (family Geminiviridae) is established. Reliable detection and identification methods are available. The pathogen is not included in the EU Commission Implementing Regulation 2019/2072. CpCDV has been reported in Africa, Asia and Oceania. It has not been reported in the EU. CpCDV infects plant species in the family Fabaceae and several species of other families (Amaranthaceae, Brassicaceae, Caricaceae, Cucurbitaceae, Malvaceae and Solanaceae), including weeds. It may induce symptoms on its hosts, causing severe yield reduction. The virus is transmitted in a persistent, circulative and non-propagative manner by the leafhopper species Orosius orientalis and O. albicinctus, which are not regulated. O. orientalis is known to be present in some EU member states. Plants for planting (other than seeds), parts of plants and cut flowers of CpCDV hosts and viruliferous leafhoppers were identified as the most relevant pathways for the entry of CpCDV into the EU. Cultivated and wild hosts of CpCDV are distributed across the EU. Would the pest enter and establish in the EU territory, impact on the production of cultivated hosts is expected. Phytosanitary measures are available to prevent entry and spread of the virus in the EU. CpCDV fulfils the criteria that are within the remit of EFSA to assess for it to be regarded as a potential Union quarantine pest.
RESUMO
The European Commission requested the EFSA Panel on Plant Health to prepare and deliver risk assessments for commodities listed in Commission Implementing Regulation (EU) 2018/2019 as 'High risk plants, plant products and other objects'. This Scientific Opinion covers plant health risks posed by defoliated and in dormant phase, grafted bare rooted plants for planting of Malus domestica imported from Moldova, taking into account the available scientific information, including the technical information provided by the applicant country. A list of 1,118 pests potentially associated with the commodity species was compiled. The relevance of these pests was assessed following defined criteria and based on evidence. The EU-quarantine pest Xiphinema rivesi non-EU populations fulfilled these criteria and was selected for further evaluation. For this pest, the risk mitigation measures proposed in the technical dossier from Moldova were evaluated taking into account the possible limiting factors. For this pest, an expert judgement is given on the likelihood of pest freedom taking into consideration the risk mitigation measures acting on it, including uncertainties associated with the assessment. The Expert Knowledge Elicitation indicated, with 95% certainty, that between 9,991 and 10,000 plants per 10,000 would be free of X. rivesi.
RESUMO
The EFSA Panel on Plant Health conducted a pest categorisation of Capsicum chlorosis virus (CaCV) for the EU territory. The identity of CaCV, a member of the genus Orthotospovirus (family Tospoviridae), is established and reliable detection and identification methods are available. The pathogen is not included in the EU Commission Implementing Regulation 2019/2072. CaCV has been reported in Australia, China, India, Iran, Taiwan, Thailand and USA (Hawaii). In the EU, it has been reported once in Greece (Crete Island). The NPPO of Greece reported that CaCV is no longer present in Greece. CaCV infects plant species in the family Solanaceae (i.e. pepper, tomato) and several species of other families, including ornamentals. It may induce severe symptoms on its hosts, mainly on leaves and fruits, which may become unmarketable. The virus is transmitted in a persistent propagative mode by the thrips Ceratothripoides claratris, Frankliniella schultzei, Microcephalothrips abdominalis and Thrips palmi. C. claratris and T. palmi are EU quarantine pests. M. abdominalis is known to be present in several EU member states and it is not regulated in the EU. Plants for planting, parts of plants, fruits and cut flowers of CaCV hosts, and viruliferous thrips were identified as the most relevant pathways for the entry of CaCV into the EU. Cultivated and wild hosts of CaCV are distributed across the EU. Should the pest enter and establish in the EU territory, impact on the production of cultivated hosts is expected. Phytosanitary measures are available to prevent entry and spread of the virus in the EU. CaCV fulfils the criteria that are within the remit of EFSA to assess for it to be regarded as a potential Union quarantine pest.
RESUMO
The European Commission requested the EFSA Panel on Plant Health to prepare and deliver risk assessments for commodities listed in Commission Implementing Regulation (EU) 2018/2019 as 'High risk plants, plant products and other objects'. This Scientific Opinion covers plant health risks posed by dormant grafted plants, rootstocks, budwood and scions of Malus domestica imported from Turkey, taking into account the available scientific information, including the technical information provided by Turkey. All pests associated with the commodities were evaluated against specific criteria for their relevance for this opinion. Three quarantine pests (Anoplophora chinensis, Lopholeucaspis japonica and tomato ringspot virus), one protected zone quarantine pest (Erwinia amylovora) and eight non-regulated pests (Calepitrimerus baileyi, Cenopalpus irani, Cicadatra persica, Diplodia bulgarica, Hoplolaimus galeatus, Malacosoma parallela, Pratylenchus loosi and Pyrolachnus pyri) that fulfilled all relevant criteria were selected for further evaluation. For E. amylovora, special requirements are specified in Commission Implementing Regulation (EU) 2019/2072. Based on the information provided in the dossier, the specific requirements for E. amylovora were not met. For Anoplophora chinensis, special measures are specified in Commission Implementing Decision (EU) 2012/138. The exporting country does meet the requirement for a certificate regarding plants for planting that originate from Turkish provinces other than Istanbul. For the 10 remaining selected pests, the risk mitigation measures proposed in the technical dossier from Turkey were evaluated taking into account the possible limiting factors. For the selected pests an expert judgement is given on the likelihood of pest freedom taking into consideration the risk mitigation measures acting on the pest, including uncertainties associated with the assessment. The degree of pest freedom varies among the pests evaluated, with D. bulgarica being the pest most frequently expected on the imported plants. The expert knowledge elicitation indicated with 95% certainty that between 9,863 and 10,000 bundles (consisting of 10 or 25 plants each) per 10,000 would be free from D. bulgarica.