Paddy weed control by higher plants from Southeast Asia

Abstract

Ten higher plant species from Southeast Asia were selected as possessing the strongest allelopathic properties during a preliminary survey conducted in 2000–2002, and tested for biological weed control in paddy fields during spring and summer seasons 2002 in Viet Nam. All species studied promoted rice growth and yield and greatly reduced paddy weed growth at a dose of 2 tons ha −1. Two species including Bidens pilosa and Tephrosia candida were the most effective candidates attaining more than 80% weed control and increasing rice yield by 20%. They were suggested for use as potential natural herbicides. The other species including Blechnum orientale, Eupatorium canabium, Euphobia hirta, Lencaena glauca, and Morus alba might be useful as alternative materials for biological weed control and for the reduction of herbicides used in paddy field.