Abstract
Pseudomonas bacteria are entomopathogenic that can naturally infect and kill insects upon ingestion. The insecticidal and plant growth-promoting roles of the bacteria were assessed by applying Pseudomonas IUK001 to insects and plants. The culture extract (CE) of IUK001 at the concentration of 1 mL/cm( )(3)of an artificial diet was used as a treatment for Galleria mellonella larvae. The CE was heat stable at 70 degrees C for 30 minutes and proteinase-K stable, showing 100% and 90% insecticidal activity against G. mellondla larvae. Gas chromatography-mass spectrometry (GC-MS) analysis revealed the insecticidal compounds, for example, trans-cinnamic acid, ornithine, and cyclo (L-Pro-L-Val) in the CE of IUK001. Antibacterial activity was assessed through minimal inhibitory concentration and half-maximal inhibitory concentration values, which ranged from 28 +/- 0.8 and 18.9 +/- 0.7 to 8 +/- 1.8 and 4.6 +/- 0.6, respectively. Moreover, plants were inoculated with IUK001, which significantly enhanced (P < 0.05) the total plant lengths (root + shoot), dry and fresh biomasses and chlorophyll content, and also induced lateral roots. Plant growth hormones, auxins: indole-3-butyric acid and indole-3- propionic acid, were then analyzed through GC-MS in the CE using their respective isotopic internal standards. The findings of the study suggest that IUK001 is a significantly valuable candidate to be exploited as a biocontrol agent as well as a plant growth promoter.