Physiological Host Specificity of Microsporidia as an Indicator of Ecological Host Specificity

• Published in: Journal of invertebrate pathology Vol. 71; no. 3; pp. 207 - 216
• Main Authors: Solter, Leellen F, Maddox, Joseph V
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Inc 01.05.1998; Elsevier
• Subjects: AGENT PATHOGENE; ALLOPATRIC SPECIES; Animals; AUXILIAIRE DE LUTTE BIOLOGIQUE; Biological and medical sciences; Biological Assay; Biological control; BIOLOGICAL CONTROL ORGANISMS; CHRYSOMELA; CHRYSOMELA SCRIPTA; classical biological control; Coleoptera - parasitology; Control; DISEASE TRANSMISSION; ecological host specificity; Endoreticulatusspp; entomopathogen; ENTOMOPATHOGENIC PROTOZOA; ESPECE; ESPECIES; ESPORAS; Fundamental and applied biological sciences. Psychology; HORIZONTAL TRANSMISSION; HOST PARASITE RELATIONS; HOST RANGE; Host-Parasite Interactions; HOSTS; HOTE; HUESPEDES; INFECTIVITY; LEPIDOPTERA; Lepidoptera - parasitology; LYMANTRIA DISPAR; MICROSPORA; Microsporida; Microsporidia; NATIVE HOSTS; NONINDIGENOUS HOSTS; Nosemaspp; ORGANISMOS PARA CONTROL BIOLOGICO; ORGANISMOS PATOGENOS; PATHOGENICITY; PATHOGENS; PATOGENICIDAD; physiological host specificity; Phytopathology. Animal pests. Plant and forest protection; Plant Leaves; POUVOIR PATHOGENE; PROTOZOA; Protozoa. Invertebrates; RELACIONES HUESPED PARASITO; RELATION HOTE PARASITE; SPECIES; SPORE; SPORES; SYMPATRIC SPECIES; TRANSMISION DE ENFERMEDADES; TRANSMISSION DES MALADIES; transmission of microsporidia; Vairimorphaspp; transmission of microsporidia; classical biological control; Endoreticulatusspp; Vairimorphaspp; physiological host specificity; entomopathogen; ecological host specificity; Nosemaspp; microsporidia; Lymantria dispar; host range; Protozoa; Entomopathogen; Laboratory study; Lymantriidae; Insecta; Biological control; Host specificity; Parasite; Nosema; Cnidosporidia; Pest; Microbiological control; Transmission from animal to animal; Arthropoda; Lepidoptera; Invertebrata; Field study
• ISSN: 0022-2011; 1096-0805
• DOI: 10.1006/jipa.1997.4740

For most groups of biological control agents the relationship between laboratory (physiological) host range and the host range in the field (ecological host range) has not been explored empirically. The objective of our study was to investigate this relationship using the North America gypsy moth,Lymantria dispar,as a model nontarget host for microsporidia from native North American Lepidoptera. The gypsy moth,L. dispar,a native of Europe, has been established in North America for nearly 130 years and presumably exposed to many species of microsporidia from sympatric native Lepidoptera. Nevertheless, microsporidia have never been observed in North American populations ofL. dispar.We conducted traditional laboratory feeding experiments using microsporidia from 20 lepidopteran host species and 1 coleopteran host species againstL. dispar.Microsporidia from 18 native hosts infectedL. disparlarvae. Although some of the infections were not typical of infections in the indigenous natural hosts, mature spores were produced in most of these infections. Horizontal transmission experiments, based on exposure of uninfectedL. disparlarvae to infectedL. disparlarvae, demonstrated that the microsporidia were far more host specific than the direct feeding experiments suggested. Of the three microsporidian biotypes that were horizontally transmitted between the nontargetL. disparlarvae, all were transmitted at very low levels. The results of our experiments provide additional evidence that the ecological host specificity of terrestrial microsporidia is much narrower than the physiological host specificity. Our studies establish the validity of using nonindigenous insect species with long-term data sets on natural enemies associated with them as a tool for testing hypotheses about host specificity.