Fig 1.
In vivo effect of plant growth promoting endophytic bacteria B. contaminans NZ.
(a) Bacterial effect significantly influences the increase in root and shoot lengths of jute seedlings when compared with the control jute plants at 4, 7, and 10 days. Comparisons of (b) shoot and root lengths, plant heights, and (c) fresh and dry weights of B. contaminans NZ-treated and control jute seeds. Error bars represent the standard error of the mean of the replicates. Shoot and root lengths are represented in cm, and fresh and dry weights in mg. Asterisk (*) denotes the difference between control and endophyte-treated samples at a significance level of P ≤ 0.05, as determined by ANOVA test. Values are mean(s) ± SD.
Table 1.
List of genes involved in plant growth promotion activity detected from RAST, antiSMASH, PIFAR analysis of the B. contaminans NZ whole genome.
Table 2.
List of major virulence related genes present or absent in B. contaminans NZ.
Fig 2.
Antagonistic properties of B. contaminans NZ against six other phytopathogenic fungi.
(a) Nigrospora sphaerica (b) Xylaria spp.(c) Aspergillus fumigatus (d) Aspergillus niger (e) Penicillium oxalicum, and(f) Rhizoctonia solani.
Table 3.
Growth inhibition induced by B. contaminans NZ on different plant pathogenic fungi.
Fig 3.
Chromogenic aberration in B. contaminans NZ challenged M. phaseolina.
(A) M. phaseolina, B. contaminans NZ, and their co-cultures on day 5. (B) M. phaseolina without B. contaminans NZ retains the black color (left) compared to its B. contaminans NZ challenged counterpart (right). Inhibition of M. phaseolina growth and its pigmentation in the presence of B. contaminans NZ is evident compared to the culture containing only M. phaseolina.
Fig 4.
Peaks from GC-MS analyses with potent volatile compounds.
(A) M. phaseolina, (B) M. phaseolina and B. contaminans NZ co-culture, and (C) B. contaminans NZ. The number on different peaks corresponds to the serial number of the compounds in Table 4.
Table 4.
List of potential compounds with their biological activities and retention times found in GC-MS analysis of B. contaminans NZ (B), M. phaseolina (M), and their co-culture (C).
Fig 5.
Identification of bioactive compounds in methanolic extract of B. contaminans NZ culture.
(A) HPLC chromatograms of the active fraction (peak at 33.2 min retention time) upon reinjection. (B) Peak which inhibits the mycelial progression of M. phaseolina towards the active fraction when applied on the well, marked by a violet arrow. (C) LC-MS chromatogram of active peak identified to be pyrrolnitrin with a mass of 257.1 Da.
Table 5.
Homologous proteins of melanin pathways found in M. phaseolina.