QUARANTINE REGULATIONS AND NEW PROBLEMS CONCERNING SEED-TRANSMITTED VIRUSES AND VIROIDS

The enforcement in EEC Member States of the Council Directive 77/93/ EEC and two amendments on protective measures against the introduction into Member States of organisms harmful to plants or plant products is expected during 1980. The points of the Directive dealing with seed-transmission of viruses and viroids are analyzed and discussed.

Recent progress in plant virus and viroid research raises new quarantine problems in regard to transmission through seed. Some of these problems are analyzed, with attention focused on cryptic viruses, viroids and satellite RNA molecules.

In the conclusion, it is recommended that plant breeders collaborate with plant virologists to a greater extent than they do at present, to be sure that they do not contribute to the selection and spread of new diseases.