Isolation and characterization of bacterial endophytes from the roots of Cassia tora L

Abstract

In the present investigation, five endophytic bacterial strains isolated from the roots of Cassia tora L. were identified as Bacillus subtilis, Agrobacterium tumefaciens, Bacillus sp., Pseudomonas putida, and Pseudomonas sp. based on biochemical characteristics as well as 16S rRNA gene sequencing. Isolates were screened for plant growth promoting traits, antibacterial activity, antifungal activity, antibiotic sensitivity, and salinity tolerance. The majority of the endophytic strains produced phytohormone indole acetic acid (IAA), ammonia, and also solubilized phosphate. Siderophore and HCN production were observed in A. tumefaciens, P. putida, and Pseudomonas sp. The antibiotic sensitivity profile indicated that the isolates were resistant to chloramphenicol, while highly susceptible to neomycin and streptomycin. Bacterial endophytes gave a definite stamp on their antibacterial activity against Escherichia coli and Klebsiella pneumoniae and antifungal activity against Pythium ultimum, Aureobasidium pullulans, and Alternaria alternata. Pseudomonas sp. showed maximum salt tolerance (6 % NaCl) contrary to A. tumefaciens that was least tolerant.

Isolation and characterization of bacterial endophytes of Curcuma longa L.

“…Endophytic bacterial isolates were characterized on the basis of colony morphology, biochemical characteristics and molecular phylogeny. The morphological and biochemical characteristics of the isolates were examined according to the Bergey’s manual of determinative Bacteriology (Kumar et al 2015 ).…”

Isolation and characterization of plant growth promoting endophytic bacteria isolated from Vigna radiata

“…Antifungal activity: The bacterial isolates producing hydrogen cyanide were tested against Aspergillus niger and Fusarium oxysporium on potato dextrose agar media for fungistatic activity. The 24 hour old bacterial isolates were streaked 1 cm away from the 2 mm of fungal disc placed on media plate and uninoculated plate with fungal disc served as negative control (Kumar et al 2015). Antifungal activity was evaluated by fungal growth inhibition after incubating the plates at 30ºC for 7 days.…”

CULTURABLE ENDOPHYTIC BACTERIA FROM HALOTOLERANT Salvadora persica L.: SCREENING, ISOLATION AND PLANT GROWTH PROMOTING TRAITS

“…The endophytic bacterial isolates reside and multiply in the plants where the environment contains relatively high ionic strength which successively tolerated both the biotic and abiotic factors. Previously many authors reported the endophytic strain which successively tolerated the high salt concentration [36][37][38][39]. In this study the endophytic isolates were able to grown differentially at different salt levels.…”

“…Endophytic bacterial isolates were characterized on the basis of biochemical characteristics by Bergey's manual of determinative bacteriology [16] and molecular phylogeny by 16S rRNA gene sequencing. Genomic DNA was isolated using GeneiPure TM bacterial DNA purification kit (Bangaluru, India) following the manufacture's protocol.…”