Effects of integrated use of organic and inorganic nutrient sources with effective microorganisms (EM) on seed cotton yield in Pakistan.

A field experiment was conducted to determine the effects of integrated use of organic and inorganic nutrient sources with effective microorganisms on growth and yield of cotton. Treatments included: control; organic materials (OM); effective microorganisms (EM); OM+EM; mineral NPK (170:85:60 kg); 1/2 mineral NPK+EM; 1/2 mineral NPK+OM+EM and mineral NPK+OM+EM. OM and EM alone did not increase the yield and yield attributing components significantly but integrated use of both resulted in a 44% increase over control. Application of NPK in combination with OM and EM resulted in the highest seed cotton yield (2470 kg ha-1). Integrated use of OM+EM with 1/2 mineral NPK yielded 2091 kg ha-1, similar to the yield (2165 kg ha-1) obtained from full recommended NPK, indicating that this combination can substitute for 85 kg N ha-1. Combination of both N sources with EM also increased the concentrations of NPK in plants. Economic analysis suggested the use of 1/2 mineral NPK with EM+OM saves the mineral N fertilizer by almost 50% compared to a system with only mineral NPK application. This study indicated that application of EM increased the efficiency of both organic and mineral nutrient sources but alone was ineffective in increasing yield.