Almost all tree species in the central European riparian forests are currently threatened by different pests and diseases. Therefore, early warning and rapid response are key requirements for effective management of forests pests and diseases.
Here we present brief overview of methods available to assist practitioners in their pests and diseases detection activities. Also, DanubeForestHealth information system is developed within REFOCuS project which allows practitioners to timely communicate occurrence of detected pests and diseases in riparian forests.
DETECTION METHODS FOR PESTS
Three main approaches for forest pests are applied, these are: visual survey for symptoms, trapping methods and other detection methods.
When using visual survey recognizing symptoms and signs of pests are most important – the most obvious characteristic may be that the tree or parts of the tree crown are dying, does not carry anymore leaves or shows discoloured leaves.
Trapping methods are characterised by using traps to catch different pests. There is a range of traps which are using different types of attractants (e.g., light traps, coloured traps, traps based on odours such as tree volatiles or pheromones) based on pest of interest.
Other detection methods can include usage of dogs or application of remote sensing methods.
DETECTION METHODS FOR DISEASES
Diseases are mostly caused by fungal or fungal-like organisms, more rarely by bacteria, viruses, and virus-like organisms.
Identification of fungal/bacterial or viral origin of symptoms in the field is based on the knowledge of specific symptoms and/or the findings and identification of specific reproductive structures of a pathogen. Symptoms are usually grouped according to plant organs they affect: leaves/needles, shoots/twigs/branches, stem, roots, and flower/fruits.
For detection of pathogens in the field, primarily based on a detailed knowledge of symptoms characteristics for target species, all symptoms including different stages of symptom development should be carefully and comprehensively documented (photos and description). Sampling for lab confirmation and diagnostics should follow special requirements for target species, but in general samples should be significant and abundant and should reflect different stages of deterioration of affected tissues.
Fungi can also be detected with spore traps.
Some fungi are insect-borne, where insects act like vectors for disease. For early detections of insect-borne diseases trap techniques with specific pheromones are used.
Symptoms and ecology of most important pest and diseases on characteristic tree species for Mura-Drava-Danube Biosphere Reserve alongside management recommendation for them are given in our book.