| Sumario: | Field trials were carried out on Apomu soil (Psammentic usthorthent) and Egbeda soil (Oxic paleustalf) in southern Nigeria to investigate the effects of fertilizer and weeding on growth and yield of maize (Zea mays L.) under no-tillage and tilled land preparations.
On the newly cleared Apomu soil, broadleaved weeds comprised the major portion of the weed flora, with the shrubs being more important under no-tillage. More grasses and sedges were present when the soil was tilled. Regardless of tillage method, there was a ⩾ 38% yield reduction due to weeds in the unfertilized plots, with yield in tilled plots being almost double that in no-tillage plots. Effect of weed competition in maize can be partially overcome by fertilization as yield reductions due to weeds were 19% ⩾ in the fertilized plots. Weeding was shown to be necessary even with a first crop following bush clearing especially when the soil fertility was low.
On both soil types maize yield responded to fertilizer application. Yield of no-tillage maize was less than that of tilled maize with no or low rates of N application, but with adequate N fertilization yield from no-tillage maize equalled that of tilled maize. Lower yield of no-tillage maize may in part be attributed to severe N stress during early growth. Consequently on low fertility soil, no-tillage maize production is not recommended without adequate N fertilization.
|
|---|