False broomrape, caused by Agrobacterium tumefaciens, causes yield losses in flue-cured tobacco in South Africa. False broomrape causes typical grown gall symptoms in tobacco - tumours, variable in size, develop on the roots of infected plants. Several biological control agents, including a commercial preparation of Agrobacterium radiobacter race 84, known for its ability to control A. tumefaciens , were evaluated over a period of three seasons for their efficacy in controlling false broomrape in tobacco. Different dosages of these agents and various application methods, such as incorporation into the growth medium during seedling production, drenching of seedling trays, liquid application during planting, and dipping of seedlings immediately prior to planting, were also evaluated. The efficacy of chemicals such as EDB, methamsodium, dazomet, methyl bromide and a quaternary ammonium compound was also evaluated during this period. Plant height, number of tumours per plant, tumour size, tumour weight and yield were determined for each treatment. None of the biological control agents, regardless of dosage or application method, was very effective in controlling the disease, reducing the A. tumefaciens population in the soil or reducing the number of galls on the infected plants. Only the dazomet and methyl bromide treatments could effectively reduce the population of A. tumefaciens in the infested soils and reduce the number, size, and weight of tumours on the roots of tobacco grown in the infested soils. Significantly higher yields were obtained from the dazomet and methyl bromide treatments. These results indicated that false broomrape had a significant negative impact on yield. However, no significant differences in the chemical analysis of the cured tobacco could be demonstrated between the different treatments. It was also shown that plants from the methyl bromide treatment had significantly fewer and smaller tumours on their root systems. A negative correlation was demonstrated between yield and total tumour mass.