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

PLISCHUK, S.; MARIOTTINI, Y.; LANGE, C. E.; CIGLIANO, M. M.

Protistology

Protozoological Society, Russian Academy of Sciences

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 outof eight grasshopper species collected at an overall prevalence of 38.8 % and amaximum of 50 %. In the Patagonia site, P. locustae was detected in four out of sixspecies at an overall prevalence of 10.5 % and a maximum of 34.3 %. Two of thespecies affected, one in the Pampas, the gomphocerine Amblytropidia australis,and one in Patagonia, the melanopline Dichroplus vittigerum, constitute new hostrecords for P. locustae, expanding its field host range in Argentina to 24 species ofgrasshoppers. In addition, bioassays were performed on three other grasshopperspecies selected based on several criteria. The tristirid Bufonacris claraziana and thegomphocerine Borellia bruneri turned out to be not susceptible to P. locustae whilethe melanopline Scotussa cliens was highly susceptible. All in all, results highlightnot only the uniqueness of P. locustae among the Microsporidia that allowed for itsdevelopment as a biocontrol agent but also the suitability of grasshopper communitiesin the Pampas and Patagonia to fully express such uniqueness, possibly even moreso as an allochthonous parasite against autochthonous novel hosts.