Off-campus UNL users: To download campus access dissertations, please use the following link to log into our proxy server with your NU ID and password. When you are done browsing please remember to return to this page and log out.

Non-UNL users: Please talk to your librarian about requesting this dissertation through interlibrary loan.

Characterizing the Expression of Biocontrol Genes by Lysobacter enzymogenes Strain C3 in vitro and in the Rhizosphere

Dongxue Shi, University of Nebraska - Lincoln

Abstract

The bacterial species Lysobacter enzymogenes has the ability to lyse other microorganisms through the production of various secondary metabolites and lytic enzymes, and several strains have demonstrated potential to be biological control agents against plant pathogens. In this study, the roles of the secondary metabolite HSAF, chitinases and β-1,3-glucanases in the biological control activity of L. enzymogenes strain C3 and the genetic factors that control the production of these metabolites are reviewed. A qRT-PCR-based method was developed to monitor in vitro and in planta the simultaneous transcription of pks-nrps, chiA and gluC, genes critical for the synthesis of HSAF, chitinase A, and β-1,3-glucanase C, respectively. In experiments conducted in broth culture, expression of each of the three genes was found to be differentially affected by altering carbon source concentration and content. When strain C3 was applied to rhizosphere environments, different temporal patterns of expression by C3 were found for the three genes. The pattern for each gene was modified depending upon the plant species to which the C3 was applied, the region of the root system assayed, and the availability of chitin supplied as an exogenous nutrient. These findings contribute to the understanding of the factors that can affect the expression of the biological control traits.

Subject Area

Plant Pathology

Recommended Citation

Shi, Dongxue, "Characterizing the Expression of Biocontrol Genes by Lysobacter enzymogenes Strain C3 in vitro and in the Rhizosphere" (2021). ETD collection for University of Nebraska - Lincoln. AAI28490603.
https://digitalcommons.unl.edu/dissertations/AAI28490603

Share

COinS