Species richness and diversity of Phytophthora spp. (water molds) in urban riparian-forest ecosystems, which serve as primary drainage passageways for surface-water runoff, may be attributed to surrounding landscape management, associated vegetation, and environmental conditions. These riparian areas, although generally small, are always flooded during wet seasons and almost completely dry during the hottest parts of each year when there is limited precipitation. Little is known about Phytophthora spp. diversity within these heavily impacted sites. We sampled water, soil, and vegetation (phenology dependent) across 14 dates, over ~2 y at a site containing a drainage ditch that enters Hog Creek, in Rankin County, MS. We cultured all Phytophthora spp. using 4 published protocols to ensure maximum isolation potential. Across all sampling dates, 65 isolations were positive for Phytophthora spp., 12 of which were recovered from vegetation. We employed morphological and internal transcribed sequence (ITS) data to confirm taxa. We determined a total of 11 taxa on the basis of their phylogenetic clustering with known species of Phytophthora in a bayesian analysis. The most common taxa were P. chlamydospora, P. mississippiae, and P. cinnamomi at frequencies of 12.5%, 11.0%, and 10%, respectively. We verified morphologically and by sequence similarity an undescribed species, Phytophthora oaksoil taxon, which has been reported previously in the Western US, as well as other countries, such as Australia. Overall, the bottle-of-bait (BOB) intact-leaf and water-filtration methods had numerically greater frequencies (P ≤ 0.05) than BOB leaf disks, soil-baiting leaf disks, or vegetationsampling protocols. Overall frequency (14%) of Phytophthora spp. was significantly greater (P ≤ 0.05) for the 17 December 2014 sampling date. Even though several taxa identified in this study are reported to be pathogenic to riparian forest trees and vegetation at the Hog Creek site, symptoms on surrounding trees and vegetation was generally limited to foliar lesions, and we observed no visible damage or decline during the study period. It would be judicious to visit different, similar urban habitats to determine if common Phytophthora in this study are present in other central and southern Mississippi riparian habitats.
You have requested a machine translation of selected content from our databases. This functionality is provided solely for your convenience and is in no way intended to replace human translation. Neither BioOne nor the owners and publishers of the content make, and they explicitly disclaim, any express or implied representations or warranties of any kind, including, without limitation, representations and warranties as to the functionality of the translation feature or the accuracy or completeness of the translations.
Translations are not retained in our system. Your use of this feature and the translations is subject to all use restrictions contained in the Terms and Conditions of Use of the BioOne website.
Vol. 17 • No. 1