Abstract: The effect of varying fertiliser levels on the response of five tobacco (Nicotiana tabacum) varieties to Striga gesnerioides infestation was studied for three seasons at a S. gesnerioides-infested site. A split-plot design with cultivar as main plot factor and three rates of basal fertiliser (0, 800, 1000 kg ha-1) and three top dressing nitrogen fertiliser rates (0, 25, 50 kg N ha-1) were investigated. Standard tobacco cultural practices were followed. Striga emergence counts were carried out at 3rd week intervals from 9 Weeks After tobacco Planting (WAP). Tobacco infestation by S. gesnerioides and tobacco yield were also assessed. Striga emergence was first noted at 12 WAP. Plots with high rates of nitrogen had fewer emerging and maturing Striga plants. Of the five tobacco varieties tested, T66 was the most tolerant to Striga infestation and two landraces, LR11 and 12 were the most susceptible. Yields of the landraces were significantly lower (p<0.05) than T66. There was a significant reduction in tobacco yield loss due to S. gesnerioides infestation when the variety T66 was grown at recommended basal rate (500 kg ha-1) combined with a higher nitrogen rate (50 kg N ha-1).
C. Koga, E. Mwenje and D. Garwe, 2011. Response of Tobacco Cultivars to Varying Fertiliser Levels in Striga gesnerioides Infested Soils in Zimbabwe. Agricultural Journal, 6: 347-352.