Research Article

Diversity of bacterial endophytes in roots of Mexican husk tomato plants (Physalis ixocarpa) and their detection in the rhizosphere

Published: December 07, 2010
Genet. Mol. Res. 9 (4) : 2372-2380 DOI: 10.4238/vol9-4gmr921

Abstract

Endophytic bacterial diversity was estimated in Mexican husk tomato plant roots by amplified rDNA restriction analysis and se­quence homology comparison of the 16S rDNA genes. Sixteen opera­tional taxonomic units from the 16S rDNA root library were identified based on sequence analysis, including the classes Gammaproteobacte­ria, Betaproteobacteria, Actinobacteria, and Bacilli. The predominant genera were Stenotrophomonas (21.9%), Microbacterium (17.1%), Bur­kholderia (14.3%), Bacillus (14.3%), and Pseudomonas (10.5%). In a 16S rDNA gene library of the same plant species’ rhizosphere, only common soil bacteria, including Stenotrophomonas, Burkholderia, Bacillus, and Pseudomonas, were detected. We suggest that the endophytic bacterial diversity within the roots of Mexican husk tomato plants is a subset of the rhizosphere bacterial population, dominated by a few genera.

Endophytic bacterial diversity was estimated in Mexican husk tomato plant roots by amplified rDNA restriction analysis and se­quence homology comparison of the 16S rDNA genes. Sixteen opera­tional taxonomic units from the 16S rDNA root library were identified based on sequence analysis, including the classes Gammaproteobacte­ria, Betaproteobacteria, Actinobacteria, and Bacilli. The predominant genera were Stenotrophomonas (21.9%), Microbacterium (17.1%), Bur­kholderia (14.3%), Bacillus (14.3%), and Pseudomonas (10.5%). In a 16S rDNA gene library of the same plant species’ rhizosphere, only common soil bacteria, including Stenotrophomonas, Burkholderia, Bacillus, and Pseudomonas, were detected. We suggest that the endophytic bacterial diversity within the roots of Mexican husk tomato plants is a subset of the rhizosphere bacterial population, dominated by a few genera.