EM introduced by Dr Higa initially was designed for improving soil quality and to speed up organic matter breakdown. Following widespread success in foliage applications boosting plant growth more time, effort and trial work has followed looking at controlling pests both insects and disease. The way EM works in controlling pests and disease is through the introduction of beneficial micro-organisms to soil and plants. Pests and pathogens are suppressed or controlled through natural processes by enhancing the competitive and antagoniostic activities of the micro-organisms i.e. through competitive exclusion. The competitive exclusion principle of ecology which states, "In ecology, the competitive exclusion principle ( Gause's law) is a proposition which states that two species competing for the same resources cannot coexist if other ecological factors are constant. When one species has even the slightest advantage or edge over another, then the one with the advantage will dominate in the long term. So when you innoculate with EM you provide an advantage and the beneficial microbes prevent pests, diseases, and pathogens via 3 pathways: 1. by taking up the physical space so that competitors have no space in which to live; 2. by taking up the resources so that competitors have no resources upon which to live; 3. by feeding upon and killing competitors directly eliminating pests, pathogens, and diseases.
In addition Lactic acid bacteria which is a major ingredient in EM will suppress pathogenic microbes both directly, and indirectly, through the production of actinomycetes. EM produces an antioxidant effect which improves the immune system of plants and animals. In vineyards where we have had most of our experience in biological disease and pest control we have seen positive effects controlling Powdery Mildew, a reduction in the incidence of Botrytis and some of the other fungal diseases such as Downey Mildew. In cropping situations EM has been successful in lessoning the impact of or stamping out incidences of Fusarium, Phytophthora, Pythium, Sclerotinia and Rhizoctonia,
Local Trial
A split block trial last season, with EM in conjunction with a sulphur/copper and synthetic fungicides, gave a very positive result in terms of suppression of PM and enhanced vine health.
Powdery Mildew Field Comparisons Marlborough 2015-2016
Question: Can EM added to a Cu/Sulphur spray programme improve the control of PM
- Trial : A block of Chardonnay with a history of high incidence of PM was chosen (Stokesay Vineyard-Springlands, contracted to Delegats)
- The spraying programme was administered by Paul Taylor and was a standard Delegats Spray program which included Cu, S and DMI’s
- The Block was split in half (45 rows in each half). One half received the standard programme and the other received in addition to the standard programme, EM at 2%. (Oct-Feb)
Results: Paul Taylor, Mike Daly and Aaron Carter (Tasman Crop), walked the block 23rd Feb 2016, and observed the following:
- Significantly improved vigor, leaf and vine health on the EM block
- Low incidence of PM on the EM block
- High incidence of PM on the Control block
Conclusion: This was an unreplicated trial therefore needs more detailed trial work to validate. However this result has given us confidence to promote this as a viable option for spraying programs targeting PM. A fully replicated trial is planned for the coming season, to further validate this result.
Overseas Trials
Powdery Mildew
In this overseas trial which looked at the Control of Vine Powdery Mildew by the use of EM Preparations. The results showed that EM preparations were highly effective against powdery mildew under medium level of infection in the field conditions, and seem to increase wine quality and some sensory characteristic. Read the full report here
In another Trial on Strawberries, EM effectively limited the occurrence of strawberry red-leaf spot (Diplocarpon earliana) and white-leaf spot (Mycosphaerella fragariae) and to a lesser extent – the powdery mildew on the fruits (Botrytis cinerea). Read the full report here
Downey Mildew
In another trial on Recent Approaches for Controlling Downy Mildew of Cucumber under Greenhouse Conditions conducted at the Plant Pathology Research Institute, Agricultural Research Centre, Giza, Egypt, it was found EM1 showed significant reduction in the severity of downy mildew in cucumber plants. Read the full trial report here
Phytopathogenic Sclerotinia Sclerotiorum
In this trial conducted in Brazil soils treated with EM were found to be suppressive to the soil-borne plant pathogenic fungus, Sclerotinia sclerotiorum. EM also improved certain soil physical properties including a decrease in hardpan density, increased soil aggregation and improved drainage. All of these benefits were obtained in half the time compared with organic biodynamic agriculture or minimum tillage. Read the full report here.
