Two different DNA fragments, one of 2.9 kilobases and the other of 5.1 kilobases, were cloned from Phytophthora citrophthora and showed no homology with DNA from plants and other related fungi. These DNA probes hybridized with DNA from 12 different P. citrophthora isolates obtained from a variety of hosts but did not hybridize with DNA from 6 P. citrophthora isolates obtained from cacao. Southe...

Phytophthora is a microbial genus that includes species causing many diseases (Erwin and Ribeiro, 1996). These species infect and kill nearly all species of deciduous fruit trees. Phytophthora crown and root rots, which are caused mainly by P. cactorum, P. megasperma, P. citrophthora, P. cinnamomi, P. cambivora, P. syringae and P. cryptogea (Sarejanni, 1935; Kouyeas, 1971; Kouyeas, 1977; Flores...

We used PCR to differentiate species in the genus Phytophthora, which contains a group of devastating plant pathogenic fungi. We focused on Phytophthora parasitica, a species that can infect solanaceous plants such as tomato, and on Phytophthora citrophthora, which is primarily a citrus pathogen. Oligonucleotide primers were derived from sequences of a 1,300-bp P. parasitica-specific DNA segmen...

Eight substances that are main components of the essential oils from three Mediterranean aromatic plants (Verbena officinalis, Thymus vulgaris and Origanum vulgare), previously found active against some phytopathogenic Fungi and Stramenopila, have been tested in vitro against five etiological agents of post-harvest fruit decay, Botrytis cinerea, Penicillium italicum, P. expansum, Phytophthora c...

In 2008 statewide surveys of symptomatic foliage of nursery plants from Tennessee resulted in isolation of 43 isolates of Phytophthora spp. This sample set includes four described species (P. citrophthora, P. citricola, P. nicotianae, P. syringae), and a provisional species of Phytophthora ('P. hydropathica'). At the same time a stream-baiting survey was initiated to recover Phytophthora from e...

Ribosomal DNA variation was used to study evolutionary relationships among five fungal-like protoctistan Phytophthora species. On the basis of morphological and ecological characteristics, four of these species--P. palmivora, P. megakarya, P. capsici, and P. citrophthora--were once thought to be related. Variation within a species was extensively studied in a fifth, outgroup species--P. cinnamo...

abstract this research was invistigated activitiy of antagonistic activity of 200 soil actinomycete isolates assayed against phytophthora parasitica and p. citrophthora in kerman provice. among all actinomycetes, strains of 19 and 29 showed high level of activity in agar disk and well-diffusion methods. in both isolates, the active substance was water and metanol soluble but insoluble in chloro...

The recent incidence of Ramorum blight, caused by Phytophthora ramorum, on many nursery crops has focused attention on improving management strategies against Phytophthora diseases in nurseries. We evaluated several chemical agents that target Oomycete pathogens for their capacity to inhibit infection of rhododendron or lilac leaves by P. ramorum (both NA strain 2027 mating type A2 and European...