Rhizobacterial Diversity of Umorok in Juvenile, Flowering, and Fruiting Stages - Abstract
Rhizosphere soil of Umorok, Capsicum chinense, was collected from juvenile, flowering, and fruiting stages to study the distinct bacteria and plant development associations. Soil samples were collected from three growth stages, serially diluted, and retrieved the pure cultures. Genomic DNA was isolated from the bacteria and amplified the 16S rRNA partial gene sequence for sequencing information. Bacteria were characterized based on the sequencing data by searching in nucleotide database. Phylogenetic tree was constructed to interpret the evolutionary relationship and diversity of the rhizobacteria. Several rhizobacteria were molecular characterized, and 127 novel bacterial strains were identified. Bacterial grouping revealed alphaproteobacteria, betaproteobacteria, gammaproteobacteria, actinobacteria, and firmicutes. Among the phyla, gammaproteobacteria were dominantly present, and majorly Pseudomonas was found. Stage specific dominant bacterial analysis of Umorok confirmed that juvenile stage was associated with 40% of Agrobacterium and Rhizobium, flowering stage was associated with 50% of Pseudomonas and Burkholderia, and fruiting stage was associated with 50% of Burkholderia.
Betaproteobacteria were found to be absent in the juvenile stage. Phylogenetic tree was constructed from the representative bacterial strains of each phyla using maximum likelihood method. Phylogenetic tree provided five distinct bacterial phyla and two clusters of gram positive and negative bacteria. The results of this study provided the comprehensive and specific rhizobacterial diversity in three growth stages of the Umorok. During the plant development, rhizobacterial community was changed. The stage specific diversity facilitates the rhizobacterial application in plant growth and health improvement.