Gibberellins synthesized by the entomopathogenic bacterium, Photorhabdus temperata M1021 as one of the factors of rice plant growth promotion

Abstract

In the present study, different types of gibberellins (GAs) in the culture filtrate (CF) of Photorhabdus temperata M1021 were quantified. The analysis of CF helped in profiling various bioactive GAs: GA₁, GA₃, GA₄, and GA₇. Several physiologically inactive GAs: GA₉, GA₁₂, and GA₂₀ were detected as well. Siderophore production was also investigated by growing P. temperata M1021 on chrome azurol-S blue agar plates. Furthermore, the strain was inoculated into ‘Waito-C’ (Oryza sativa L.) rice plants, which significantly (P < 0.05) increased plant growth attributes such as plant length, chlorophyll content, and fresh and dry biomass compared with those in controls. In a separate experiment, canola (Brassica napus L.) seeds treated with CF of M1021 were significantly (P < 0.05) accelerated germination rate as well as biomass production. Findings of the present study suggest that the strain M1021 contributes an important role in the plant growth by synthesizing a wide array of bioactive metabolites.

Keywords:

• bacterization
• gibberellins
• Photorhabdus temperata
• siderophore

Funding

This research was supported by the Basic Science Research Program through the National Research Foundation of Korea funded by the Ministry of Education [grant number NRF-2013R1A1A2010298].

Supplemental data

Supplemental data for this article can be accessed at http://dx.doi.org/10.1080/17429145.2014.942956.

Additional information

Funding

Funding: This research was supported by the Basic Science Research Program through the National Research Foundation of Korea funded by the Ministry of Education [grant number NRF-2013R1A1A2010298].