THE NEED FOR AN INTERNATIONAL CERTIFICATION SCHEME OF IMPROVED TREE FRUIT PROPAGATION MATERIAL FOR DEVELOPING COUNTRIES

In recent years, considerable effort has been devoted to the establishment of modern tree fruit production schemes in developing countries.
This effort has been essentially directed at two objectives: the improvement of the nutrition status of local populations and the increase of farmers¹ income through an augmented volume of high value crops also suitable for export.
This international effort has been assisted by bilateral and multilateral aid agencies and, occasionally, by investment funds made available by oil-producing countries.
In this connection, the initiatives of joint private enterprises from developing and developed countries have also been important.

All this has created an expansion of the acreage planted to fruit trees and a great demand for propagation material.
To meet this demand, large quantities of nursery stock have been produced in various countries, quite often without sufficient consideration regarding its health status.
A large part of this material has also moved in international trade to be used for establishing new plantings in distant areas.

There is no reliable information on the phytosanitary status of this material and no data to quantify the dimensions of this problem.
Some ideas on the health status could, however, be derived indirectly from the literature.
For example, some of the published results of indexing tests conducted in the United States for the detection of viruses or virus-like agents in plant propagation material imported under quarantine in that country (9; 10) could be considered a good random sample faithfully representing the actual phytosanitary situation of material moving in international trade.
In fact, such a sample has been derived from a sufficiently diversified area over an adequately long period of time to give confidence in the interpretation of the results.

The summarized data of this work for the periods 1957–67 and 1968–78 are shown in Table 1. From these data, it appears that nearly 51 percent of trees of Prunus species were infected by viruses.
For Pyrus and Malus spp., this value is in the order of 41 and 68 percent respectively.
If one considers that the majority of such introductions were derived from better-than-average sources (collections of research institutes or of selected nurseries), it can be presumed that the phytosanitary status of commercial material used in international trade would not be any better.
It is also interesting to note in Table 1 that deciduous trees are no exception to the overall

XII International Symposium on Fruit Tree Virus Diseases

L. Chiarappa

https://doi.org/10.17660/ActaHortic.1983.130.48