Abstract

Lindani Ncube, Pearson Nyari S. Mnkeni and Marc Olivier Brutsch

A field experiment was conducted during the 2004-2005 summer season to evaluate the agronomic suitability of effective microorganism (EM) for improvement of crop productivity and quality through enhanced soil microbial activities and pest and disease suppression. Tomato (Lycopersicon esculentum Mill) was used as a test crop. Treatments included: control, effective microorganism, mineral fertilizer, effective microorganism + mineral fertilizer, compost, compost + effective microorganism, compost + mineral fertilizer and compost + mineral fertilizer + effective microorganism. Application of EM significantly increased the number of fruited tomato plants, seven weeks after transplanting. However, application of EM alone or in combination with other amendments had a depressive effect on tomato yield owing to an outbreak of early and late blights which affected the EM treatments first. Combined applications of EM with amendments improved plant N content and increased soil N content above initial levels. Compost application resulted in higher soil N and P concentrations than those of the control due to nutrients released during mineralization of the compost material.