Effects of Vermicomposts on Plant Growth

The use of organic matter such as animal manures, human waste, food wastes, yard wastes, sewage sludges and composts has long been recognized in agriculture as beneficial for plant growth and yield and the maintenance of soil fertility. The new approaches to the use of organic amendments in farming have proven to be effective means of improving soil structure, enhancing soil fertility and increasing crop yields. Organic matter are excellent source of plant-available nutrients and their addition to soil could maintain high microbial populations and activities (Pascual et. al. 1997; Zink and Allen 1998) with increased values of biomass C, basal respiration, biomass C:total organic C ratio, and metabolic quotient (qCO2). Crop yields have increased with the corresponding improvements in soil quality from additions of organic matter. Significant yield increases using mulches from coffee husks (Bwamiki, 1998) and increases in productivity using animal manures and hay residues (Johnston et al. 1995) have been reported. Their important roles in the soil and their potentially positive effect on crop yields have made organic amendments a valuable component of farm fertilization and management programs in alternative agriculture. Forms of organic matter used include crop residues as mulches, among others.