Scientific Opinion on the risk to plant health posed by <em>Phialophora cinerescens</em> (Wollenweber) van Beyma for the EU territory, with the identification and evaluation of risk reduction options

The Panel on Plant Health conducted a pest risk assessment for Phialophora cinerescens (Wollenweber) van Beyma (the causal agent of Phialophora carnation wilt) for the EU territory, identified risk management options and evaluated their effectiveness. The risk assessment was conducted taking into account current EU legislation. The Panel also provided an opinion on the effectiveness of the present EU requirements against this organism, listed in Council Directive 2000/29/EC. Four pathways for entry were identified. Plants for propagation (rooted and unrooted cuttings of host plants) were considered as a major pathway. Entry via this pathway was rated as unlikely because of the effective disease prevention techniques for cuttings now in place in places of production. P. cinerescens has been found in most Member States but with few occurrences or restricted distribution. In some Member States the pest was eradicated. Owing to current cultural practices and control measures, establishment in areas in which the pest was not previously present is considered very unlikely. For the same reasons, the probability of infection of crops is strongly reduced and hence the probability of spread to areas where the pest was not previously present is very unlikely. Similarly, the impact on carnation is at the moment minimal and unlikely to increase in the future. Risk reduction options to reduce the probability of entry and spread and mitigate the impact were evaluated; those addressing the phytosanitary status of the propagation material were considered to be the most effective and feasible (e.g., the officially accepted carnation certification system for source planting material), including the current regulations laid down in Council Directive 2000/29/EC. If the current regulation were removed, a certification system could be just as effective as the existing regulation, provided it included practically all the prescriptions of the present regulation

Scientific Opinion on the risk to plant health posed by &lt;em&gt;Chrysanthemum stunt viroid&lt;/em&gt; for the EU territory, with identification and evaluation of risk reduction options

The Panel on Plant Health conducted a pest risk assessment for Chrysanthemum stunt viroid (CSVd) and identified and evaluated risk reduction options, particularly those listed in Council Directive 2000/29/EC. Three entry pathways were identified, with plants for planting being the most important and rated as moderately likely. CSVd is recorded in some EU Member States with a limited distribution and is regulated on chrysanthemum; host plants are widely cultivated in greenhouses and outdoors. Therefore, establishment is very likely. Short-distance spread within a crop is likely, whereas short-distance spread between different species is unlikely to moderately likely. For vegetatively propagated species, in the absence of an efficient certification system, long-distance spread is very likely and a major impact would be expected on chrysanthemum, with associated yield and quality losses. However, under the existing certification scheme for chrysanthemum plant propagation material, the probability of spread through infected cuttings is largely reduced and the direct consequences of viroid outbreaks are expected to be minor. Minimal impact is predicted for other ornamental hosts and a minor impact for solanaceous vegetable crops. The indirect effects of CSVd are considered to be limited, with the exception of eradication. Risk reduction options addressing the sanitary status of the propagation material are likely to be the most effective and feasible. These include the current EU measures, as well as a statutory certification system with associated statutory import requirements or, failing that, but potentially less effective, the use of voluntary industry standards. It is difficult to disentangle the benefits of the current legislation from those of the industry-developed chrysanthemum certification system. The high efficacy of current measures is supported by the absence or limited presence of CSVd in the EU and by the limited number of interceptions and findings. Possible improvements to current measures are described and uncertainties discussed