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.