|Brussels, 14th January 2015
Recommendation of the Working Group on the Annexes of the Council Directive 2000/29/EC – Section II – Listing of Harmful Organisms as regards the future listing of Xanthomonas campestris pv. phaseoli (Smith) Dye1
Current regulatory status
Xanthomonas campestris pv. phaseoli (Smith) Dye is currently listed in Annex IIAII (b).7 of Council Directive 2000/29/EC on seeds of Phaseolus L..
Specific requirements on its host plants are laid down as part of Annex IVAI (51) and IVAII (29) to require that seeds originate from a pest free area or have been tested and found free from X. campestris pv. phaseoli; Annex VA and Annex VB as regards plant passport for movement of seeds of Phaseolus within and a plant health certificate for import into the European Union.
Plants of Phaseolus are also covered under Council Directive 2002/55/EC on the marketing of vegetable seeds and Council Directive 2008/72/EC on the marketing of vegetable propagating and planting material, other than seed.
Identity of the pest
The disease named “common blight of beans” (CBB) was formerly identified as Xanthomonas campestris pv. phaseoli. Nowadays the causal agents of CBB have proven to be genetically diverse. There are several strains belonging to two species currently known as Xanthomonas fuscans subsp. fuscans (Xff) and Xanthomonas axonopodis pv. phaseoli (Xap).
Reliable detection and identification tests are available.
Distribution of the pest
The causal agents of CBB are distributed worldwide; in 11 EU Member States they are absent, while in 17 Member States they are distributed to a limited extent. As the host is an annual crop, and the pest does not survive in the soil, the distribution is more related to the distribution of infected seed lots, so it is variable each year.
Potential for establishment and spread in the PRA area
CBB is known to occur in warm conditions (25-30°C). The climatic conditions are widely favorable for the disease except in northern EU Member States. The main host Phaseolus vulgaris is common in many EU member states but rarely produced in Denmark, Estonia, Finland, Ireland and Luxemburg. There are further natural hosts in the EU but others than Phaseolus vulgaris are not expected to play an important role in the spread of CBB.
Long distance dispersal occurs mainly through contaminated seeds. Bacteria in/on the seed survive longer than the seed itself. A few infested seeds can cause an outbreak of the disease. Short-distance dispersal results from water (rain/irrigation) splashes, infected plant debris, epiphytic populations and through human operations in fields. CBB affects yield and the quality of the beans. The production of seeds, as well as the production of fresh and dry beans are affected by the pest. Xap and Xff seem to be not very persistent after an outbreak because free living in the soil and survival in absence of a host is unlikely according to EFSA.
Potential for consequences in the PRA area
CBB is the most important bacterial disease in common bean production. Resistant cultivars are not available. No environmental impact from CBB agents is identified.
The quarantine status is no longer justified as it does not meet the requirements of ISPM 11. The Working Group suggests listing Xff and Xap as two separate species with a Regulated Non-Quarantine Pest status2.
Xff and Xap can cause severe impact; the primary pathway is plants for planting; natural spread over long distances doesn’t occur; there are no environmental impacts to be expected; clean seeds and hygiene are effective means for the control of CBB.
Equivalent requirements for imports and movement of host plants have to be set in order to retain the same level of protection.
The Pest Risk Assessment of EFSA does not need to continue.