Journal of Applied Microbiology, Vol.122, No.4, 1092-1100, 2017
Translocation of Bacillus thuringiensis in Phaseolus vulgaris tissues and vertical transmission in Arabidopsis thaliana
AimsTo demonstrate the ability of Bacillus thuringiensis to penetrate as spore-crystal complex to the internal tissues of bean plants, and keep its insecticidal activity. To test the vertical transmission of the spore-crystal complex in Arabidopsis thaliana. Methods and ResultsThe experimental strain was transformed with the pMUTIN-gfp plasmid which labelled the spores of B. thuringiensis HD-73 with the GFP protein. Once the rhizosphere of the bean plants was inoculated with the labelled strain, the bacterium was recovered from leaves, stems, and petioles. Furthermore, toxicity of treated plants was significantly higher than control plants when bio-assayed on cabbage looper larvae. The labelled strain was recovered from the dead insects. When the rhizosphere of A. thaliana plants was inoculated with the labelled strain, mature seeds from these plants were surface-sterilized and grown under invitro conditions. The labelled strain was recovered from the seedlings. ConclusionsWe showed that B. thuringiensis subsp. kurstaki (HD-73) in the rhizosphere can translocate to upper tissues of bean plants, and keep its insecticidal activity. Transmission of the labelled B. thuringiensis strain passed to the next generation of A. thaliana. Significance and Impact of the StudyThe role of B. thuringiensis as a potential facultative endophyte bacterium and the possible biotechnological repercussions are discussed.