Open AccessPhytophthora nicotianae Can Cause Both Crown Rot and Foliage Blight on Phlox paniculata in South Carolina
Author(s) -
Daniel T. Drechsler,
S. N. Jeffers,
William C. Bridges
Publication year - 2014
Publication title -
plant health progress
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.565
H-Index - 9
ISSN - 1535-1025
DOI - 10.1094/php-rs-14-0020
Subject(s) - blight , biology , phytophthora nicotianae , phytophthora , ornamental plant , horticulture , botany , collar rot , potting soil , root rot , inoculation , crown (dentistry) , rhizoctonia , rhizoctonia solani , medicine , dentistry , sclerotium
Phytophthora nicotianae is a common pathogen of many herbaceous perennial plants, and this pathogen has been found causing disease on garden phlox (Phlox paniculata) in wholesale nurseries in South Carolina for a number of years. However, the relationship between P. nicotianae and garden phlox has not been studied or reported previously. Using Koch's postulates and standard inoculation methods for Phytophthora spp., P. nicotianae was found to cause crown rot on P. paniculata when potting medium was infested with colonized vermiculite and to cause foliage blight when aerial parts of the plant were inoculated with an aqueous suspension of zoospores. Foliage blight was more similar to symptoms we observed on garden phlox plants in wholesale nurseries, but crown rot also has been observed previously on plants in these nurseries. The cause of these two diseases was confirmed, but reproduction of Phytophthora foliage blight under experimental conditions was inconsistent. Thus, other factors not yet identified may play a role in the development of Phytophthora foliage blight on garden phlox in nurseries in South Carolina. Accepted for publication 1 September 2014. Published 1 November 2014.