Crop Yields as Influenced by Land Preparation Methods Established Within Vetiver Grass Alleys for Sustainable Agriculture in Southwest Nigeria

Abstract

A 5-year experiment was conducted to investigate the effects of land preparation methods established within vetiver grass alleys (VGA) on runoff, soil loss, and soil erodibility and crop yields. Vetiver grass alleys of 5 m and 10 m intervals were established across a 6% slope, with a plot without vetiver grass strips (VGS) as a control. These treatments were replicated three times in a randomized complete block design on runoff plots measuring 40 m long by 3 m wide. Runoff and soil were in the order of plot without vetiver >10 m VGS >5 m VGS. Soil erodibility (K) was higher in plot without vetiver followed by 10 m VGS and least by 5 m VGS under all land preparation methods. Soil quality was improved as a result of complementary effects of fallow and long-term vetiver grass alleys establishment. Vetiver grass alleys significantly increased the yields of maize, okra, sweet potato, and yam tubers under different land preparation methods to varying degrees.

Keywords:

• scattered mounds
• contoured mounds
• crop yields
• vetiver grass alleys
• soil quality