Location: Floral and Nursery Plants ResearchTitle: Transgenic expression of Lactoferrin imparts resistance to a soilborne fungal pathogen Rhizoctonia solani Author
Submitted to: Planta
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/5/2011
Publication Date: 3/11/2012
Citation: Nguyen, T., Lakshman, D.K., Han, J., Mitra, A. 2011. Transgenic expression of Lactoferrin imparts resistance to a soilborne fungal pathogen Rhizoctonia solani. Journal of Plant Pathology. 2(1):1-8. Interpretive Summary: Root rot diseases and damping off account for the largest percentage of loss in commercial ornamental and vegetable production, and the fungus Rhizoctonia solani is a major causative agent. This pathogen was once successfully controlled by methyl bromide - a pesticide recently banned due to environmental concerns. Control of the pathogen with conventional pesticides is sometimes unreliable. An integrated approach using conventional control methods with introduced genetic resistance has been shown by others to be a useful means of plant protection. In this study, transgenic tobacco and Arabidopsis plants expressing an antimicrobial bovine lactoferrin gene were evaluated for resistance against Rhizoctonia solani. Transgenic tobacco plants and Arabidopsis seedlings exhibited high levels of resistance to the pathogen. Use of the lactoferrin gene is a potential new approach to consider for control of diseases caused by fungal pathogens.
Technical Abstract: Transgenic tobacco (Nicotiana tabacum var Xanthi) and Arabidopsis (A. thaliana) plants expressing an antimicrobial bovine lactoferrin (BLF) gene were developed and evaluated for resistance against an economically important fungal pathogen Rhizoctonia solani, the causal agent of damping off diseases. The plants were transformed with Agrobacterium strain C58C1 containing a plasmid construct carrying a modified BLF cDNA. The introgression of BLF cDNA into susceptible tobacco and Arabidopsis lines was confirmed by Southern blot and the expression of full-length lactoferrin transcript and protein was also detected by Northern and Western blots, respectively. Transgenic lines segregating for a single locus insertion were identified and used for disease resistance assays. Transgenic tobacco plants exhibited high levels of Rhizoctonia resistance in detached leaf assays. Similarly, transgenic Arabidopsis seedlings were resistant to the fungus and did not exhibit damping off symptoms. Use of the lactoferrin gene is a potential new approach to consider for control of diseases caused by fungal pathogens.