02024nas a2200169 4500008004100000022001400041245009100055210006900146260001200215300001300227490000700240520151100247100001901758700001501777700002001792856004201812 2007 eng d a0191-291700aPhytophthora species associated with diseased woody ornamentals in Minnesota nurseries0 aPhytophthora species associated with diseased woody ornamentals  c01/2007 a97 - 1020 v913 a

Phytophthora species are responsible for causing extensive losses of ornamental plants worldwide. Recent international and national surveys for the detection of P. ramorum have led to the finding of previously undescribed Phytophthora species. Since no previous Phytophthora surveys have been carried out in Minnesota, surveys of ornamental nurseries were performed over 4 years to isolate and identify the Phytophthora species causing diseases of woody plants in Minnesota. Species were identified by direct sequencing of internal transcribed spacer (ITS) rDNA, β-tub, and mitochondrial coxI genes. Species associated with diseased ornamental plants include P. cactorum, P. cambivora, P. citricola, P. citrophthora, P. hedraiandra, P. megasperma, P. nicotianae, and the previously identified but undescribed taxon P. Pgchlamydo. The most common species encountered were P. cactorum, P. citricola, and P. citrophthora. Two additional isolates obtained did not match known species. One was similar to P. alni subsp. alni, and the other appeared to be a new species and is referred to as P. sp. MN1. In addition, species are reported for the first time from several hosts. Results indicated that several Phytophthora species were more widespread in the nursery industry than previously thought, and undescribed species were causing disease in Minnesota ornamental nurseries.

1 aSchwingle, B W1 aSmith, J A1 aBlanchette, R A uhttp://dx.doi.org/10.1094/PD-91-0097