The seeds used for the production of plants are often of indigenous origin. However, when supply is lacking, seeds of foreign origin are used. These seeds are mostly sourced from other European countries, but sometimes from third countries. A broad diversity of ornamental conifer seeds - sometimes belonging to the same genera as our forest species - are also imported into Belgium.
Unlike other commodities such as seedlings, wood or bark, the problem of seeds of woody plants acting as vectors in the transmission of diseases is underestimated. There is therefore little or no control from a phytosanitary point of view. However, recent research has shown that the seeds of woody species can transport many fungi, some of which are pathogenic. The risk of emerging diseases linked to international trade in conifer seeds is therefore largely unknown, and needs to be studied within the context of increasing trade and climate change.
To assess this risk, the ALERTSEED project was launched in July 2021 for a period of 30 months. It is a collaboration of two scientific partners - the CRA-W (coordinator) and the Proefcentrum voor Sierteelt (PCS) - and consists of two study sections. The first is concerned with the collection of data from nurserymen, foresters, seed suppliers and regional authorities, to quantify the extent of the overseas purchase of conifer seeds, identify the conifer species (forest or ornamental), and determine the trends in forest species in the future. The second aims to develop a method for the detection of fungi associated with conifer seeds using high throughput sequencing technology (broad spectrum detection method), and to apply this method to batches of seeds from Belgium, other European countries, or other continents. The results of the project will help improve our understanding of the risk presented by international conifer seed trade in the transmission of emerging fungi.
Illustration: Abies nordmanniana seeds (used for the production of Christmas trees) - photo by CRA-W
Funding: FPS Public Health and Food Chain Safety