HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Submit a response Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in ISI Web of Science Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Enright, S. M. Articles by Cipollini, D. Search for Related Content PubMed Articles by Enright, S. M. Articles by Cipollini, D. Agricola Articles by Enright, S. M. Articles by Cipollini, D.

Infection by powdery mildew Erysiphe cruciferarum (Erysiphaceae) strongly affects growth and fitness of Alliaria petiolata (Brassicaceae)¹

Department of Biological Sciences, Wright State University, 3640 Colonel Glenn Highway, Dayton, Ohio 45435 USA

ABSTRACT

Garlic mustard (Alliaria petiolata) is an invasive biennial that negatively impacts plant and animal communities throughout North America and lacks significant herbivory in its invasive range. Throughout Ohio, many garlic mustard populations support the powdery mildew fungus Erysiphe cruciferarum, although disease incidence varies among populations and environments. Effects of infection on plant growth, as well as both plant and fungal responses to drought and light conditions, were examined on greenhouse-grown, first-year garlic mustard plants. Also, the effects of the fungus on plant growth and fitness were studied in a naturally growing population of second-year plants in the field. Powdery mildew significantly reduced growth of first-year plants in the greenhouse, eventually causing complete mortality. Simulated drought slowed both plant growth and disease development, independent of light conditions. In the field, plants with little incidence of disease after their first year grew taller during their second year, producing significantly more siliques and twice as many seeds as heavily diseased plants did. Seed germination rates did not differ between plants with different levels of disease severity. Consistent reductions in survival, growth, and fitness caused by fungal infection may reduce populations of garlic mustard. These effects may be more evident in moist sites that favor fungal development.

Key Words: Alliaria petiolata • biocontrol • Erysiphe cruciferarum • infection • invasive species • plant fitness • plant growth