Assessing the effectiveness and benefits of conventional and minimum tillage on weed management in Maize (Zea mays L.)
Abstract
In Kenya maize is the staple food crop with 80% of the population using it as the main human food and its shortage always causes food crisis threatening economic and political stability. Weeds are a major constraint to maize production due to the associated losses and increased costs of their management. Weeds alone can cause an estimated 80% yield loss in maize depending on species and abundance. The aim of the study was to identify a suitable tillage practice for better management of weeds in maize to increase production, The trial was conducted in Kigumo District near Gatumbi market during the long and short rain seasons in 2010. The treatments comprised of two maize varieties DUMA SC41 and DK8031, four tillage practices glyphosate, conventional, intercropping and weedy. The experiment was laid out in a randomized complete block design (RCBD) and replicated three times.
Data on weeds and maize were collected from each plot and analyzed using Gen Stat software package and ANOV A was used to assess the effects of different treatments. Treatments means were separated using Student New Man Keuls and Statistical difference determined at p < 0.05. Results for weed count and dry weight biomass showed that glyphosate was more effective in suppressing the weeds than hand weeding. There were no significant differences between glyphosate and hand weeding in maize grain yield in short and long rain seasons. Cost benefit analysis for the two tillage practices showed that glyphosate produced higher returns than hand weeding.
Weed count and biomass dry weight results for mono crop and intercrop showed that intercropping was more effective in weed suppression than monocrop.: Intercropping increased maize yield for the two maize varieties overall by 47.9% more than mono crop and reduced labour costs. Glyphosate and intercropping had no significant differences for the parameters assessed in both seasons. Glyphosate and intercropping each reduced weed population by 63.6% and 64.4% respectively compared with the weedy/control. Performance of glyphosate and intercropping were not significantly different but since glyphosate may not be affordable by majority of small scale farmers, they should be encouraged to grow maize intercropped with Dolicos lablab to manage the weeds, improve maize yield, reduce cost of herbicide or weeding and achieve better utilization of land and labour.
Publisher
University of Nairobi, Kenya