Evaluation ofAlternaria macrosporaas a Potential Biocontrol Agent for Spurred Anoda (Anoda cristata): Host Range Studies

Abstract

The host range of an isolate of the fungal pathogenAlternaria macrosporaZimmerman from infected spurred anoda [Anoda cristata(L.) Schlecht.] leaves was studied in the greenhouse and growth chamber. The fungus was inoculated to representative plants in the Malvaceae, Solanaceae, Leguminosae, and Gramineae families. Evidence of infection was limited to plants in the Malvaceae, with spurred anoda being the most susceptible species tested. Only negligible damage was incited on cotton (Gossypium hirsutumL. ‘Stoneville 213′) and long staple cotton (G. barbadenseL. ‘Pima S–5′), hollyhock [Althaea rosea(L.) Cav.], okra (Hibiscus esculentusL. ‘Clemson spineless’), prickly sida (Sida spinosaL.), velvetleaf (Abutilon theophrastiMedic.), and Venice mallow (Hibiscus trionumL.). Disease symptoms induced in cotton by the spurred anoda isolate ofA. macrosporawere much less severe than those reported for other isolates of the fungus. Therefore, the spurred anoda isolate may be a specialized form of the fungus.