Comparison of the Germination Conditions of Two Large-Spore Microsporidia Using Potassium and Sodium Ion Solutions

SIMPLE SUMMARY: In this study, we investigated the germination conditions of the large-spore microsporidia Trachipleistophora sp. FOA-10 and Vavraia sp. YGSL-2015-13. The germination rates of the microsporidia were determined using a combination of four different treatment solutions and two test temperatures and were compared to those of Trachipleistophora sp. OSL-2012-10 and Nosema bombycis, which have known germination conditions. We found that the two types of microsporidia germinated in physiological salt solution. These differences in germination rates were affected by the preservation solution and temperature. ABSTRACT: The germination of a microsporidian polar tube generally occurs under alkaline conditions. Typically, microsporidian spores can be stored in physiological salt solution for short periods. However, because of differences in the lodging area, the requirements may not always be uniform. In fact, Trachipleistophora sp. OSL-2012-10 (nomen nudum Trachipleistophora haruka) germinated when preserved in physiological salt solution. In this study, the germination characteristics of the large-spore microsporidia Trachipleistophora sp. FOA-2014-10 and Vavraia sp. YGSL-2015-13 were compared with those of Trachipleistophora sp. OSL-2012-10; moreover, we investigated whether these characteristics are specific to these microsporidia. We found that both microsporidia germinated in physiological salt solution. These differences in germination rates were affected by the preservation solution and temperature.