Influence of triclopyr and nitrogen on management of Striga hermonthica on sorghum

Purpose - The purpose of this paper is to study the effects of the herbicide triclopyr, nitrogen and their combinations on Striga incidence and sorghum growth. Design/methodology/approach - A greenhouse study was undertaken in season 2013. Sorghum cv Wad Ahmed, urea and triclopyr were employed. Treatments were arranged in a randomized complete design with four replicates. Findings - Nitrogen alone suppressed the parasite completely early in the season. Triclopyr at 0.3 and 0.4 kg a.e.ha(-1) reduced Striga emergence by 92.9 and 58.3 per cent early and late in the season, respectively. Triclopyr at 0.3 kg a.e.ha(-1) applied subsequent to nitrogen at 43.8 kg ha(-1) effected poor control of the parasite. Unrestricted Striga parasitism reduced sorghum height and chlorophyll content by 50.38 and 16.62 per cent, respectively. Triclopyr, nitrogen and their combination improved sorghum growth considerably. Originality/value - The results suggest that the herbicide when applied subsequent to nitrogen afforded the most consistent performance and resulted in the highest suppression of the parasite.