Detection of soil-borne pathogens in glasshouse-grown ornamentals*

The Research Station for Floriculture and Glasshouse Vegetables focuses its activities on the entire glasshouse horticulture chain. Research involves many different ornamental crops, each with its own specific problems with respect to pest control. Correct diagnosis of diseases is very important in order to give good advice for control strategies. With the introduction of integrated and supervised control strategies, pathogen monitoring has become even more important. In general, diagnosis is carried out by conventional methods using selective media to isolate and identify the pathogen. These methods can be time-consuming and result in the identification of a single pathogen at a time. Diagnostic methods based on isozyme patterns have also been used for the detection of fungal pathogens in infected plant material. Specific isozyme methods have been developed for the diagnosis of Fusarium oxysporum f. sp. cyclaminis in cyclamen, F. oxysporum f. sp. gladioli in gladiolus, Gnomonia radicicola in rose, and Phytophthora nicotianae, Phytophthora sp. and Cylindrocladium spathiphylli in spathiphyllum. Current and future work is focussing on identification of plant pathogens in contained environment-culturing systems using molecular techniques.