Influence of "effective microorganisms" (EM) on vegetable production and carbon mineralization - A preliminary investigation

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 degrees 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.