Effective Microorganisms (EM) Co-applied with Organic Wastes and NPK Stimulate the Growth, Yield and Quality of Spinach (Spinacia oleracea L.)

Effective microorganisms (EM) are increasingly being applied to stimulate nutrient cycling and plant growth. However, information regarding its co-application with organic wastes and chemical fertilizers on enhancing spinach yield is scarce. A pot experiment was conducted at Gomal University D.I. Khan, Pakistan, during 2009-10 to study the changes in soil fertility and spinach growth after the application of EM with organic wastes and chemical fertilizers. The six treatments were; control (T0), 10 tons (t) ha^-1 farm yard manure (FYM) (T1), 20 t ha^-1 pressmud (T2), 0.7 t ha^-1 compost (T3), 5 t ha^-1 poultry manure (T4) and mixed chemical fertilizer in the ratio of 100 : 40 : 56 kg ha^-1 as N, P and K (T5). Each treatment was applied alone and with EM. Results showed that EM + pressmud combination significantly improved soil physical and chemical properties as well as spinach growth compared to other fertilizers with EM. Maximum soil organic matter content (OM) and K was observed in treatment where pressmud was co-applied with EM. While greater N and P were found where compost and poultry manure were co-applied with EM respectively. Significant (P 0.05) increase in plant height (11%), number of leaves (124%), fresh foliage yield (136%), dry foliage yield (16.4%), leaf length (20.2%) and leaf area (77.4%) were noted where pressmud + EM was applied as compared to its corresponding treatment without EM. Maximum Fe, Cu and Mn concentrations were found where pressmud + EM was applied. Dietary fiber, vitamin C and crude proteins were also increased in spinach with pressmud + EM application. It was concluded that EM-inoculated pressmud has higher potential to increases soil fertility as well as stimulate spinach growth and quality. Therefore, warrants further testing under field conditions.