Diversity analysis of endophytic bacteria within Azolla microphylla using PCR-DGGE and electron microscopy

Abstract

Using 16S rDNA-PCR-DGGE, electron microscopy and conventional plating method, genetic diversity and phenotype polymorphism of the endophytic bacteria within Azolla microphylla were explored. 16S rDNA-PCR-DGGE profile showed that there was a complex and divergent bacterial community with Bacillus cereus as dominant species within Azolla-cyanobacteria association, which was supported by the fact that the endobacterial cells exhibited distinct ultrastructural characteristics in vivo and the bacteria appeared various colonies with different size, shape and colors in vitro. It indicated that the genetic diversity of endophytic bacteria in Azolla could be figured out by using 16S rDNA-PCR-DGGE.