Influence of “Effective Microorganisms” (EM) on Vegetable Production and Carbon Mineralization–A Preliminary Investigation

ABSTRACT The influence of effective microorganisms (EM), a commercially available microbial inoculant containing yeasts, fungi, bacteria and actinomycetes, was evaluated in field trials of commercially produced, irrigated vegetable crops on "organic" farms in Canterbury, New Zealand during 1994–1995, and in a laboratory incubation. EM plus molasses were both applied, at 10 L ha□ 1 in 10,000 L ha□ 1 water, three times to the onions, twice to the peas and seven times to the sweetcorn. EM plus molasses increased the onion yield by 29% and the proportion of highest grade onions by 76%. EM plus molasses also increased pea yields by 31% and sweetcorn cob weights by 23%. A four week incubation at 30°C of loamy sand and 1% w/w pasture litter had treatments including a control, glucose, and EM plus glucose, and captured respired carbon (C) using NaOH traps. By the end of the incubation the glucose treatment had respired 38% more C than the control. The EM treatment respired an additional 8% more C than the glucose treatment. Using EM stimulated C mineralization in the laboratory incubation, but a corresponding increase in mineralization of organic nitrogen, phosphorus and sulphur was not measured. KEYWORDS: Effective microorganismsvegetable yieldpeassweet-cornonioncarbon mineralizationNew Zealand