Naturalized, newly-associated microsporidium continues causing epizootics and expanding its host range

CARLOS E. LANGE,; MARIOTTINI YANINA; PLISCHUK SANTIAGO; CIGLIANO MARÍA MARTHA

Protistology

Protozoological Society Affiliated with RAS

Año: 2020 vol. 14 p. 32 - 37

1680-0826

Examination of grasshoppers sampled at two sites, one in western Pampas and onein northwestern Patagonia, both in Argentina, revealed the occurrence of two newepizootic events of the allochthonous microsporidium Paranosema locustae whichbecame naturalized in grasshopper communities of those areas after introductionsfrom its native land in North America in the late seventies-early eighties and midnineties, respectively. In the Pampas site, P. locustae was found infecting six out of eight grasshopper species collected at an overall prevalence of 38.8 % and a maximum of 50 %. In the Patagonia site, P. locustae was detected in four out of six species at an overall prevalence of 10.5 % and a maximum of 34.3 %. Two of the species affected, one in the Pampas, the gomphocerine Amblytropidia australis, and one in Patagonia, the melanopline Dichroplus vittigerum, constitute new host records for P. locustae, expanding its field host range in Argentina to 24 species of grasshoppers. In addition, bioassays were performed on three other grasshopper species selected based on several criteria. The tristirid Bufonacris claraziana and the gomphocerine Borellia bruneri turned out to be not susceptible to P. locustae while the melanopline Scotussa cliens was highly susceptible. All in all, results highlight not only the uniqueness of P. locustae among the Microsporidia that allowed for its development as a biocontrol agent but also the suitability of grasshopper communities in the Pampas and Patagonia to fully express such uniqueness, possibly even more so as an allochthonous parasite against autochthonous novel hosts.