Olpidiopsis sp., an oomycete from Madagascar that infects Bostrychia and other red algae: Host species susceptibility

摘要: SUMMARY Olpidiopsis sp. (Oomycota) was cultured with its original host Bostrychia moritziana (Sonder ex Kutzing) J. Agardh from Madagascar. Bean-shaped zoospores two heterokont flagella attached to the cell wall surface and in 2 days cells began collapsing one or more syncytia developed each infected cell. Zoospores were cleaved an exit tube a small plug formed. Complete development zoospore discharge occurred 3 days. Infection of polysiphonous branches, monosiphonous rhizoids reproductive stichidia. Dead plants treated microwave not infected. Susceptibility variable other species different countries. Agardh, radicans (Montagne) Montagne Madagascar susceptible but tenella (J. V. Lamouroux) J. Agardh isolate not. B. radicosa (Itono) J. A. West, G. C. Zuccarello et M. Hommersand isolates Madagascar, Thailand, Australia New Caledonia Malaysia B. radicans Mexico Brazil non-susceptible as flagellifera Post, harveyi Montagne, montagnei Harvey, simpliciuscula Harvey J. Agardh, tenuissima R. J. King Puttock, Stictosiphonia intricata(Bory de Saint-Vincent) P. C. Silva, kelanensis (Grunow) Puttock tangatensis (Post) Lophosiphonia sp., Neosiphonia Polysiphonia spp. also non-susceptible. Many strains showed initial cell-collapse followed by rapid wound-repair formation without sporangia developing. Caloglossa leprieurii G. Martens periaxial cells, wing died became purple wound-repair. ogasawaraensis Okamura postiae Kamiya had no symptoms infection. Dasysiphonia chejuensis I. K. Lee J. A. West Surprisingly, conchocelis phase blade Porphyra pulchella A.West, C. Zuccarello suborbiculata Kjellman The tenera linearis Greville stages tested. miniata (C. Agardh) C. Agardh dentata Bangia atropurpurea (Roth) gametophyte filaments Other red, brown green algae Time lapse videomicroscopy spore release done.