Root-knot nematodes (Meloidogyne spp.) are important pests of many cultivated plants. Recently, the most efficient chemical control products (e.g. methyl bromide) have now been restricted due to ...their toxic characteristics. Research on agents that work against root-knot nematodes and do not have a detrimental impact on the environment is becoming increasingly important. Advances in the last decades produced quite a number of biocontrol products that are already marketed. Some of the well-accepted commercial products contain bacteria Bacillus firmus and Pasteuria penetrans, and fungus Purpureocillium lilacinus. In this review we summarize the antagonistic activity of bacteria and fungi, with their advantages and limitations in biocontrol of root-knot nematodes.
The Panel on Plant Health performed a pest categorisation of the strawberry bud weevil, Anthonomus signatus Say, (Coleoptera: Curculionidae), for the EU. A. signatus is a well‐defined and ...distinguishable species, recognised as a pest of strawberry (Fragaria) fruit production in eastern North America where it is also a pest of Rubus. There are reports of A. signatus associated with non‐rosaceous plants such as Mentha, Nepeta, Rhododendron and Solidago although whether such plants are true hosts is uncertain. This pest categorisation focuses on Fragaria and Rubus as hosts. Anthonomus signatus is not known to occur in the EU. It is listed in Annex IIAI of Council Directive 2000/29/EC. The international trade in Fragaria and Rubus plants for planting provides a potential pathway to introduce A. signatus from North America. Considering climatic similarities between North America and the EU, the thermal biology of A. signatus and host distribution in the EU, A. signatus has the potential to establish within the EU. There would be one generation per year, as in North America. As a pest of field grown Fragaria and Rubus, A. signatus would not be expected to establish in EU glasshouses. In North America, adults clip developing buds, preventing fruit development and reducing yield. Losses are variable and depend on the cultivars attacked. Severe crop losses have been reported. However, some Fragaria cultivars can compensate the loss of buds, e.g. by increasing the weight of fruits developing on remaining buds. Phytosanitary measures are available to reduce the likelihood of introduction of A. signatus from North America. All criteria assessed by EFSA for consideration as a potential Union quarantine pest are met. As A. signatus is not known to occur in the EU, this criterion assessed by EFSA to consider it as a Union regulated non‐quarantine pest is not met.
Following a request from the European Commission, the EFSA Panel on Plant Health performed a pest categorisation of the seed‐borne bacterium Curtobacterium flaccumfaciens pv. flaccumfaciens. The pest ...is regulated in Council Directive 2000/29/EC (Annex IIB) as a harmful organism whose introduction into, and spread within, the protected zones (PZ) of Greece, Portugal and Spain shall be banned if present on seeds of Phaseolus vulgaris and of Dolichos. The bacterium is widely distributed outside the EU and causes a systemic vascular disease (bacterial wilt of bean) as well as bacterial tan spot disease on soybean. The pest was sporadically recorded in several EU Member States in the past, but is currently not known to occur in the EU. The identity of the bacterium is well established and identification methods are available. The major host is common bean (Phaseolus vulgaris), but other crops and weeds are, or may be, hosts or play a role as reservoirs, with uncertainties. Seed transmission remains uncertain for minor and alternative host species. The main pathway for entry is seed. The role of other pathways (e.g. irrigation water and infected residues) is uncertain. Should the bacterium enter the EU (including the PZ), it may establish, spread and have an impact on its host crops. The use of healthy seeds is the most effective control measure. Curtobacterium flaccumfaciens pv. flaccumfaciens fits all the criteria assessed by EFSA to be regarded as a Union quarantine pest.
•Detection and discrimination of plant stress origin using hyperspectral imaging.•Nematode infestation can be reliably differentiated from the water deficiency.•Abiotic drought resulted in the most ...obvious differences in the light spectrum.•Identification of nematode infestation possible with specific spectral regions.•Reliable prediction of nematode infestation even in early stages of infestation.
Crop plants are subjected to various biotic and abiotic stresses. Both root-knot nematodes (biotic stress) and water deficiency (abiotic stress) lead to similar drought symptoms in the plant canopy. In this work, hyperspectral imaging was used for early detection of nematode infestation and water deficiency (drought) stress in tomato plants. Hyperspectral data in the range from 400 to 2500 nm of plants subjected to different watering regimes and nematode infestation levels were analysed by partial least squares – discriminant analysis (PLS-DA) and partial least squares – support vector machine (PLS-SVM) classification. PLS-SVM classification achieved up to 100% accuracy differentiating between well-watered and water-deficient plants, and between 90 and 100% when identifying nematode-infested plants. Grouping the data according to the time of imaging increased the accuracy of classification. Shortwave infrared spectral regions associated with the OH and CH stretches were most relevant for the identification of nematode infested plants and severity of infestation. This study demonstrates the capability of hyperspectral imaging to identify and discriminate between biotic and abiotic plant stresses.
The Panel on Plant Health performed a pest categorisation of the non‐EU Pissodes spp. (Coleoptera: Curculionidae). They constitute a well‐defined taxon, with non‐EU species distributed in the USA, ...Canada, Mexico, Guatemala, El Salvador, China, Japan, Korea, Russia and South Africa, some of which are recognised as severe pests of conifers, mainly Pinus spp. and Picea spp., or vector pathogens. The immature stages either live in the phloem and cambium of healthy, weakened or dead trees, or in the terminal shoots of living trees. They are listed as quarantine pests in Annex IAI of Directive 2000/29/EC. Plants for planting, branches of conifers and non‐squared wood are considered as pathways. The pest can also disperse by hitchhiking, and fly over kilometres. The adults are long‐lived (up to 4 years). They feed by puncturing the bark of stems or shoots. Females lay eggs in chewed‐out cavities in the bark. The life cycle varies with species and local climatic conditions. At the end of the larval stage, the larva excavates a pupal cell between the sapwood and the bark, in the sapwood or in terminal shoots. Pissodes spp. overwinter as adults in the litter or as larvae or teneral adults in the galleries or pupal cells. The current geographic range of the non‐European Pissodes spp. suggests that many of them may establish in the EU territory, where their hosts are widely present. We list some species which, if introduced to the EU, would most probably have an economic impact on plantations or may interfere with forest ecosystem processes although they are mainly abundant and damaging in intensively managed monocultures. All criteria for considering those non‐EU Pissodes spp. as potential quarantine pests are met. The criteria for considering them as non‐regulated quarantine pests are not met because they are absent from the EU territory.
The EFSA Panel on Plant Health performed a pest categorisation of the Citrus leprosis viruses for the EU territory and identified five distinct viruses, Citrus leprosis virus C (CiLV‐C), Citrus ...leprosis virus C2 (CiLV‐C2), Hibiscus green spot virus 2 (HGSV‐2), the Citrus strain of Orchid fleck virus (OFV) and Citrus leprosis virus N sensu novo (CiLV‐N) as causing this severe disease, most significantly in sweet orange and mandarin. These viruses have in common that they do not cause systemic infections in their hosts and that they all are transmitted by Brevipalpus spp. mites (likely but not confirmed for HGSV‐2). Mites represent the most important means of virus spread, while plants for planting of Citrus are only considered of minor significance. These well characterised viruses occur in South and Central America. Leprosis is currently regulated in directive 2000/29 EC and, together with its associated viruses, has never been recorded in the EU. All five viruses have the potential to enter into, establish in and spread within the EU territory, with plants for planting of non‐regulated hosts, fruits of Citrus and hitch‐hiking of viruliferous mites identified as the most significant pathways. Given the severity of the leprosis disease, the introduction and spread of the various viruses would have negative consequences on the EU citrus industry, the magnitude of which is difficult to evaluate given the uncertainties affecting the Brevipalpus spp. vectors (identity, distribution, density, transmission specificity and efficiency). Overall, leprosis and its five associated viruses meet all the criteria evaluated by EFSA to qualify as Union quarantine pests, but do not fulfil those of being present in the EU or of plants for planting being the main spread mechanism to qualify as Union regulated non‐quarantine pests. The main uncertainties affecting this categorisation concern the Brevipalpus spp. mite vectors.
Following a request from the European Commission, the EFSA Plant Health (PLH) Panel performed a pest categorisation of Bretziella fagacearum, a well‐defined and distinguishable fungal species of the ...family Ceratocystidaceae. The species was moved from the genus Ceratocystis to a new genus Bretziella following phylogenetic analysis of the species and its close relatives. The former species name Ceratocystis fagacearum is used in the Council Directive 2000/29/EC. The pathogen is regulated in Annex IAI as a harmful organism whose introduction into the EU is banned. B. fagacearum is only reported from the USA, where it causes a wilt disease on Quercus spp. Other hosts are reported based on inoculation trials, although Chinese chestnut (Castanea mollissima) is reported to be naturally infected. No North American oak species has been found to be immune to the disease. The European oak species Quercus robur, Quercus petraea and Quercus pubescens were found to be susceptible in inoculation experiments. The pest could enter the EU via wood (with and without bark, including wood packaging material), plants for planting and cut branches. Hosts and favourable climatic conditions are common in the EU, thus facilitating establishment. The pest would be able to spread following establishment by means of root grafts, insect vectors and movement of wood, plants for planting and other means. The pest introduction would have impacts in woodland and plantations, as oak wilt disease is often lethal in a short period of time. Wood treatment (debarking, kiln drying, fumigation), prompt removal of affected trees and creating root‐free zones between affected and healthy stands are available control measures. The main knowledge gaps concern (i) the survival of the fungus in wood during transport and the association with propagation material, (ii) the presence of suitable vectors in Europe and (iii) the relative susceptibility of the oak species native to Europe under natural conditions. The criteria assessed by the Panel for consideration as a potential quarantine pest are met. For regulated non‐quarantine pests, the criterion on the pest presence in the EU is not met.
Following a request from the European Commission, the EFSA Plant Health (PLH) Panel performed a risk assessment for Atropellis spp. in the EU focusing on the risk of entry, the host range and the ...potential impacts. Atropellis is a fungal pathogen of several Pinus spp. in North America. The pathogen has not been reported from Europe and is a quarantine pest regulated in Annex IIAI of Council Directive 2000/29/EC on plants (other than fruit and seeds), isolated bark and wood of Pinus. The main pathways of entry considered were Pinus plants, wood and isolated bark. Given the ban of importing Pinus plants from outside Europe into the EU and the lack of information on EU imports of isolated Pinus bark, only the wood pathway was assessed quantitatively. The conclusion of the assessment of entry for scenario A0 (current regulatory situation) is that the risk of entry of Atropellis spp. is close to zero. This conclusion is expected to apply also in the case of removing the specific Atropellis regulations, because of the remaining generic Pinus requirements, as well as in a scenario with additional risk reduction options. The uncertainty associated with this assessment is relatively limited, given that all the quartiles of the estimated distribution of the number of potential founder populations are close to zero. For the North American Pinus spp. known to be susceptible and widely planted in the EU (mainly P. contorta and P. strobus), the damage observed in North America (loss of wood quality, stem deformations, mortality in young stands, environmental consequences) is expected in the EU to a similar (or higher) degree, should the pathogen be introduced. Similar impacts are expected on the European Pinus spp. known to be host of Atropellis spp. These include widespread and locally abundant species such as P. nigra, P. sylvestris and P. pinaster. There are, however, large uncertainties associated with this impact assessment due to the unknown susceptibility of several other Pinus spp. present in Europe. There is a need for research on the susceptibility to Atropellis spp. of those European Pinus spp.
Following a request from the European Commission, the EFSA Panel on Plant Health performed a pest categorisation of Guignardia laricina, a well‐defined and distinguishable fungal species of the ...family Phyllostictaceae. The pathogen is regulated in Council Directive 2000/29/EC (Annex IAI) as a harmful organism whose introduction into the EU is banned. G. laricina is native to East Asia and causes a shoot blight disease of Larix spp. Major hosts of G. laricina are European larch (Larix decidua) and two North American larch species (Larix laricina (tamarack) and Larix occidentalis (Western larch)). Larix kaempferi (Japanese larch) is reported as susceptible. The only other host in nature is Douglas fir (Pseudotsuga menziesii), which is reported as an incidental host, but various other conifers have been reported as susceptible following artificial inoculation, including Picea abies. The fungus is not known to occur in the EU but could enter via plants for planting (including artificially dwarfed plants) and cut branches of Larix spp. It could establish in the EU, as hosts are present and climatic conditions are favourable. The pathogen would be able to spread following establishment by natural dissemination of ascospores and pycnospores and by human movement of infected plants for planting. Should the pathogen be introduced in the EU, impacts can be expected in larch forests, plantations and nurseries, leading to reduced tree growth and ecosystem service provision. The key uncertainties concern the current distribution and level of impacts in the native range of the pathogen. The criteria assessed by the Panel for consideration as a potential quarantine pest are met. As the pest is not present in the EU, not all criteria for consideration as a regulated non‐quarantine pest are met.
Following a request from the European Commission, the EFSA Panel on Plant Health performed a pest categorisation of Coniferiporia sulphurascens and Coniferiporia weirii, two well‐defined and ...distinguishable fungal species of the family Hymenochaetaceae. The pathogens are regulated in Council Directive 2000/29/EC (Annex IAI, under the previous name Inonotus weirii for both species) as a harmful organism whose introduction into the EU is banned. The two pathogens are native to North America, where C. sulphurascens causes laminated root rot primarily in Douglas fir (Pseudotsuga menziesii) and grand fir (Abies grandis), while C. weirii causes cedar laminated root and butt rot mainly in cedars (Thuja plicata and Cupressus nootkatensis). C. weirii has been reported from Japan and China, and C. sulphurascens from China, Russia and Turkey. Neither species has been reported from the EU. C. sulphurascens may infect all conifers, while C. weirii is reported to mainly cause disease in tree species of Thuja spp. and Cupressus spp. The two pathogens could enter the EU mainly via wood with bark, isolated bark and plants for planting (including artificially dwarfed plants) of Pinaceae and Cupressaceae. Both fungi could establish in the EU, as hosts are present and climatic conditions are favourable. The two pathogens would be able to spread following establishment by the pathways mentioned for entry and also by dissemination of basidiospores and root contact with infected root/wood. Should the pathogen be introduced in the EU, impacts can be expected on coniferous woodlands, plantations and ornamental trees, thus leading to reduced tree growth and ecosystem service provision. The key uncertainties concern (i) the distribution of the two pathogens in Asia, (ii) the level of susceptibility of conifers native to Europe and (iii) the role of plants for planting as a pathway of entry and spread. For both pathogens, the criteria assessed by the Panel for consideration as a potential quarantine pest are met. As the two pests are not present in the EU, not all the criteria for consideration as regulated non‐quarantine pests are met.
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