01289nas a2200133 4500008004100000245007700041210006900118300001600187490000700203520077400210100001400984700001600998856014101014 1983 eng d00aPhytophthora pseudotsugae, a new species causing root rot of Douglas-fir0 aPhytophthora pseudotsugae a new species causing root rot of Doug a2626–26310 v613 a

Phytophthora pseudotsugae n. sp. was isolated from rotted roots of Douglas-fir growing in forest tree nurseries in Oregon and Washington. It is distinguished by large oogonia and oospores, mostly paragynous antheridia, and predominantly spherical or ovoid, persistent sporangia borne primarily on simple and unbranched sporangiophores. Sporangia are formed occasionally in liquid culture, rarely in solid media. Phytophthora pseudotsugae is distinguished most readily from P. cactorum by its unbranched sporangiophores and persistent sporangia. It also differs in growth on defined media, electrophoretic protein patterns, and pathogenicity. Comparison is also made with P. iranica, the other species in group 1 of Waterhouse.

1 aHamm, P B1 aHansen, E M uhttp://rparticle.web-p.cisti.nrc.ca/rparticle/AbstractTemplateServlet?calyLang=eng&journal=cjb&volume=61&year=1983&issue=10&msno=b83-289