Efficacy and economic comparison of weed management in tomato

Abstract

ABSTRACT Weed interference in tomato (Solanum lycopersicum L.) reduces fruit yield and economic return under tropical conditions for smallholder growers who pay for labor. Field experiments were conducted in a tropical forest-savanna transition zone to evaluate the efficacy and economic benefits of hand weeding, herbicides and their combination in tomato cultivation. Pre-emergence application of propaben® (metolachor+prometryn) and butachlor, each at 2 kg∙ha−1, plus hand weeding at 40 days after transplanting reduced weed density and biomass, and increased weed control efficacy (57–64%) less than the weed-free check (100%) and better than two hand weedings (45%), or either herbicide applied alone (34–38%). Propaben® or butachlor plus hand weeding increased number of leaves and branches, number of fruit and fruit yield of tomato similar to the weed-free check and better than two hand weedings, or either herbicide applied alone. Although the weed-free check gave similar fruit yield, propaben® or butachlor plus hand weeding was 37–44% higher in net return. Application of propaben® or butachlor alone gave comparable net returns to two hand weedings and the weed-free check, but had a 61–88% higher cost-benefit ratio. Multiple hand weeding did not guarantee the highest yield or net return and increased cost of production. The combination of propaben® or butachlor plus hand weeding will provide higher tomato yield and net return through efficient weed control at relatively lower cost.