The paper summarizes information on the raising up menace of ornamental and forest nurseries by Phytophthora spp. caused mostly by P. cinnamomi, P. citricola, P. citrophthora, P. cryptogea, P. ramorum. Some Phytophthora species are especially detrimental, but their identification is not possible on the basis of symptoms. To detect and identify pathogens in the plants (with- and without symptoms), soil and water, reliable tests are required. The survey on methods and techniques reported in the literature which can be used to establish such assays is given. The most needed are the tests based on DNA markers, especially when organized as micro-chips due to the large number of samples which can be screened in a short time.