Abstract
Seven morphologically different yeast-like symbiotes were isolated from eggs of the rice brown planthopper, Nilaparvata lugens. To determine their taxonomic affiliation, molecular analysis of DNA encoding 18S-ribosomal RNA was carried out. PCR amplifications of their DNA preparations using the well conserved regions of Saccharomyces cerevisiae 18S-rDNA as primers produced a single main band of DNA having the predicted size of 1.3 and 1.6Kbp on electrophoresis. Digestion of these DNAs with restriction endonucleases gave different band patterns on electrophoresis, indicating that these seven yeast-like microorganisms belong to different taxonomic affiliations.