The fungus Fusarium semitectum infects the flowering heads of Rudbeckia auriculata at two sites in Alabama. This is the first report of a fungal agent infecting this globally rare species. The fungus produces orange-tinged or pinkish-white spores on the flower heads and renders infected flowers sterile. Fungal spores superficially resembled pollen and are picked up by the main pollinator, the composite specialist bee Andrena aliciae, which serves as a dispersal agent for the fungal pathogen. Fungal spores were found attached in higher ratios in those areas of the bee's body that come into most direct contact with the flowering heads during feeding. The rate of spread of the fungus on potted plants indicated significant negative correlations between number of infections and the distance from the fungal source. Fusarium colonies were isolated from the entire length of flowering stems, and apparently invade vegetative portions of the plants. As R. auriculata is a perennial plant that reproduces almost exclusively by the production of short stolons, the fungus poses no serious threat to its immediate existence.
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.