Pratylenchus vulnus Allen et Jensen and Cylindrocarpon destructans (Zins.) Scholten on rose in soilless culture.

The combined presence of Pratylenchus vulnus Allen et Jensen and Cylindrocarpon destructans (Zins.) Scholten, on rose (Rosa canina Linn.), in soilless culture and in field is reported. The morphobiometrical data of the nematode and the fungus and some information on their biology, geographical distribution, pathogenicity and relative damages are described. On the ground of the observations performed, Authors reached the conclusion that harmful organisms may cause greater damages on soilless than on field cultures. This can be explained by the fact that plant parasites and pathogens usually do not find antagonists in a hydroponic habitat. In case of replant a choice not to be underrated concerns the convenience to recover the old substrate or to replace it with a new one. The recovery needs a sterilization, very onerous treatment, also the new substrate is cause of problems of not little entity for the discharge of the old ones. It is emphasized, at last, the importance, above all in soilless cultures, of the use of certified material in the new systems.