Title: | Detrimental and neutral effects of a wild grass-fungal endophyte symbiotum on insect preference and performance |
Author(s): | Clement SL; Hu J; Stewart AV; Wang B; Elberson LR; |
Address: | "USDA, ARS Plant Germplasm Introduction and Testing Research Unit, 59 Johnson Hall, Washington State University, Pullman, WA 99164-6402, USA. stephenclement08@gmail.com" |
ISSN/ISBN: | 1536-2442 (Electronic) 1536-2442 (Linking) |
Abstract: | "Seed-borne Epichloe/Neotyphodium Glenn, Bacon, Hanlin (Ascomycota: Hypocreales: Clavicipitaceae) fungal endophytes in temperate grasses can provide protection against insect attack with the degree of host resistance related to the grass-endophyte symbiotum and the insect species involved in an interaction. Few experimental studies with wild grass-endophyte symbiota, compared to endophyte-infected agricultural grasses, have tested for anti-insect benefits, let alone for resistance against more than one insect species. This study quantified the preference and performance of the bird cherry oat-aphid, Rhopalosiphum padi (L.) (Hemiptera: Aphididae) and the cereal leaf beetle, Oulema melanopus (L.) (Coleoptera: Chrysomelidae), two important pests of forage and cereal grasses, on Neotyphodium-infected (E+) and uninfected (E-) plants of the wild grass Alpine timothy, Phleum alpinum L. (Poales: Poaceae). The experiments tested for both constitutive and wound-induced resistance in E+ plants to characterize possible plasticity of defense responses by a wild E+ grass. The aphid, R. padi preferred E- over E+ test plants in choice experiments and E+ undamaged test plants constitutively expressed antibiosis resistance to this aphid by suppressing population growth. Prior damage of E+ test plants did not induce higher levels of resistance to R. padi. By contrast, the beetle, O. melanopus showed no preference for E+ or E- test plants and endophyte infection did not adversely affect the survival and development of larvae. These results extend the phenomenon of variable effects of E+ wild grasses on the preference and performance of phytophagous insects. The wild grass- Neotyphodium symbiotum in this study broadens the number of wild E+ grasses available for expanded explorations into the effects of endophyte metabolites on insect herbivory" |
Keywords: | Animals Aphids/*physiology Coleoptera/*physiology Epichloe/*physiology Female *Host-Parasite Interactions Phleum/*microbiology/parasitology Polymerase Chain Reaction Symbiosis; |
Notes: | "MedlineClement, Stephen L Hu, Jinguo Stewart, Alan V Wang, Bingrui Elberson, Leslie R eng 2011/08/27 J Insect Sci. 2011; 11:77. doi: 10.1673/031.011.7701" |