Certification scheme for fruit trees in Germany
2006
Lenz, F., Institut fuer Gartenbauwissenschaft, Bonn (Germany) | Lankes, Chr., Institut fuer Gartenbauwissenschaft, Bonn (Germany)
After World War II a programme was started in Germany for the selection of healthy efficient mother trees for the further propagation of rootstocks and scion cultivars. It was shown that virus-free trees showed better compatibility, growth, yield, fruit quality than infected ones. Also they proved to be more tolerant towards stress and replant problems. Therefore it was ensured that mother plants became virus-free. From 1978 onwards the usage of virus-free planting material was compulsory. However, this decree was softened by a new European Union order in 1992 giving the growers free choice for certified plant material or material of minor health status. For quick marketing of new cultivars i.e. clonal material it allows to propagate planting material from mother plants of which the origin is known and which are true to cultivar, healthy and free of symptoms caused by pests and diseases. Therefore only visual tests have to be passed. With this procedure there is no guarantee for freedom of latent infections by economically important virus and phytoplasma diseases. In the paper statistics are given about number of nurseries and the annual fruit tree requirement of Germany. Procedures of mother plant selection, of virus elimination and certification are described. Finally data are given about the advantage of using virus-free planting material for sustaining yields and high fruit quality.
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