Abstract
Three effective methods for controlling weeds in a crop of Plantago ovata Forsk, were indentified (a) use of a high seeding rate (12 kg ha-1), (b) pre-planted application of 1.5 kg a.i. ha-1 diuron [N’- 3,4-diochlorophenyl)-N,N- dimethylurea] and (c) post-emergence applications of 0.1 1 a.i. ha-1 paraquat [1,1’ – dimethyl- 4,4’-bipyridinium ion] (with surfactant) 28 days after planting. Growth of P. ovata was not reduced by any method, whereas weed biomass at harvest was reduced by up to 80%, leading to significant increases in seed and top growth yields of P. ovata. High population densities of P. ovata gave an additive benefit to the use of diuron and paraquat; the herbicides used together did not give any improvement over either alone.
