Management of Striga asiatica in maize in the Planalto Central of Angola - legumes and grass trap intercropping

Abstract

Maize intercropped field trials with the legumes Desmodium uncinatum cv. D. Silver leaf, Cajanus cajan, Mucuna pruriens, Tephrosia sp. and Crotalaria sp. and the trap grass Tripsacum laxum were conducted from 2008 until 2010, at Chianga, Huambo, Angola, to evaluate the effect of intercropping for the control of Striga asiatica and maize cv. SAM3 yield. Greenhouse trials with the trap grass T. laxum in clean and infested soils with the parasitic plant were also carried on. T. laxum grown in infested soils by S. asiatica both in greenhouse and field trials significantly duplicated weed seed emergence, comparatively with the sown of maize alone. By other side, in the maize-legumes trials, the results show that the intercropping of maize with legumes significantly reduced S. asiatica infestation and gave significantly higher grain yield of maize. These studies have confirmed the potentials of Tripsacum laxum as trap crop combined with maize x legume intercropping in the management of S. asiatica. Based on these results, this cultural strategy could reduce the parasitic plant seed bank and increase soil fertility and consequently maize yield.