@ARTICLE {AYONGWA:2006, title = {Root nitrogen concentration of sorghum above 2% produces least Striga hermonthica seed stimulation}, author = {Ayongwa, G. and Stomph, T. and Emechebe, A. and Kuyper, T. W. }, journal = {Annals of Applied Biology}, year = {2006}, volume = {149}, number = {3}, pages = {255--262}, }