Effective microorganism

Some studies stated that Effective microorganisms (EM-A, EM-Bokashi) show no effect on yield and soil microbiology in field experiments as bio-fertilizer in organic farming. Many of the so-called 'pit additives' used for improving the performance of sanitation systems, namely pit latrines, septic tanks and wastewater treatment plants, are also based on EM. Despite the claims made by manufacturers, available studies which have used scientific methods to investigate these additives have come to the conclusion that long-term beneficial effects are not proven. One trademarked product was originally (c. 1985) marketed as EM-1 Microbial Inoculant. Such EM blends include: In his presentational essay 'EM: A Holistic Technology For Humankind', Higa states:'I developed a mixture of microbes, using the very common species found in all environments as extensively used in the food industry–namely Lactic Acid Bacteria, Photosynthetic Bacteria an Yeasts (..) EM (..) was developed by accident (..)' The concept of 'friendly microorganisms' was developed by Professor Teruo Higa, from the University of the Ryukyus in Okinawa, Japan. He stated in the 1980s that a combination of approximately 80 different microorganisms was capable of positively influencing decomposing organic matter such that it reverts into a 'life promoting' process. Higa invoked a 'dominance principle' to explain the asserted effects of his 'Effective Microorganisms'. He claimed that three groups of microorganisms exist: 'positive microorganisms' (regeneration), 'negative microorganisms' (decomposition, degeneration), 'opportunist microorganisms' (regeneration or degeneration). Higa stated that in every medium (soil, water, air, the human intestine), the ratio of 'positive' and 'negative' microorganisms was critical, since the opportunist microorganisms followed the trend to regeneration or degeneration. Therefore, he claimed that it was possible to positively influence the given media by supplementing with 'positive' microorganisms. The concept has been challenged and no scientific studies support its main claims. This was acknowledged by Higa in a 1994 paper co-authored by Higa and soil microbiologist James F Parr. They conclude 'the main limitation...is the problem of reproducibility and lack of consistent results.'. Various experimenters have examined the use of EM in making organic fertilizers and investigated the effects of the fermented organic fertilizer on soil fertility and crop growth, not distinguishing the effects of the microorganisms in the EM treatments from the effect of the EM nutrient solution in the carrier substrate. The resulting effects on crop growth depend nonspecifically upon multiple factors, including effects of the introduced EM nutrient solution with microorganisms, effects of the naturally microorganism-rich bio-organic fraction in the soil, and indirect effects of microbially-synthesized metabolites (e.g., phytohormones and growth regulators). The effectiveness of ″Effective Microorganisms (EM)″ was investigated scientifically in an organic farming field experiment between 2003-2006 at Zürich, Switzerland, differentiating the effects of the EM microorganisms from the effects of the EM nutrient solution in the carrier substrate of the EM treatments. 'The experiment was arranged to separate the effect of the microorganisms in the EM treatments (EM-Bokashi and EM-A) from its substrate (sterilized treatments).' EM microorganisms showed no effect on yield and soil microbiology as bio-fertilizer in organic farming. Observed effects related to the effect of the nutrition rich carrier substrate of the EM preparations. 'Hence ‘Effective Microorganisms’ will not be able to improve yields and soil quality in mid term (3 years) in organic arable farming.'