We are proud to announce that new EMNZ research has been published in the international scientific journal Archives of Agronomy and Soil Science.
The paper, “Agronomic performance of EM-based biological amendment programmes across commercial cropping and pasture systems in New Zealand,” was authored by Paul Daly and Mike Daly and published online on 24 September 2026.
The article is open access, meaning farmers, advisers, researchers and members of the agricultural industry can read the complete paper free of charge.
Read the published research here
Research grounded in New Zealand farming
Biological inputs are attracting increasing interest as growers look for ways to improve crop performance, soil function and nutrient-use efficiency. However, biological products also need credible field evidence showing how they perform under genuine commercial conditions.
Our paper brings together results from EM-based biological amendment programmes used across several New Zealand cropping and pastoral systems. These included wheat, maize, pasture, lucerne and fodder beet grown in different regions, seasons and production environments.
Rather than relying solely on controlled laboratory or glasshouse studies, the paper examines outcomes from practical field programmes under the variable conditions experienced by New Zealand growers.
Key results reported in the paper
The programmes produced encouraging agronomic responses across several farming systems:
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Wheat: EM Foliar Enhance increased grain yield from 7.22 to 9.08 tonnes per hectare—an increase of 25.9%. This treatment was statistically greater than the untreated control after adjustment for multiple comparisons.
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Waikato maize: The EM-treated programme produced 34.2 tonnes of dry matter per hectare compared with 30.0 tonnes for the control—an increase of 14%.
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Hawke’s Bay maize: Plant-Stim used within a reduced-nitrogen programme produced 29.45 tonnes of dry matter per hectare compared with 23.94 tonnes for the control—an increase of approximately 23%.
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Pasture: The biological programme increased accumulated pasture dry-matter production by approximately 23% while also producing encouraging changes in clover content and root development.
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Lucerne: Plant-Stim-treated lucerne produced a cumulative yield of 10,590 kilograms of dry matter per hectare compared with 6,718 kilograms for the untreated control—an increase of 57.6%.
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Fodder beet: The EM-based treatment produced an approximately 6% increase in yield.
The results should be interpreted within the design and conditions of each individual trial. They do not mean that the same response will occur on every farm or in every season. However, the consistency of positive responses across several crops and farming systems provides valuable field evidence and a strong basis for further independent, replicated research.
Why peer-reviewed publication matters
Before being accepted, the paper was assessed through the journal’s peer-review process. This involved independent academic reviewers examining the research methods, analysis, interpretation and presentation of the results.
Peer review does not turn field results into universal guarantees. What it does provide is external scientific scrutiny and a transparent, permanent research record that other researchers and agricultural professionals can assess.
For EMNZ, publication represents an important step in connecting practical on-farm experience with formal scientific evaluation.
Supporting productive and efficient farming systems
One of the most important themes emerging from the research is the potential role of biological amendments within integrated crop and nutrient-management programmes.
These products are not presented as simple replacements for sound agronomy, adequate nutrition or good soil management. Their value lies in how they may complement these practices by supporting plant development, biological activity, root growth and the efficient use of available resources.
The maize result achieved within a reduced-nitrogen programme is particularly relevant as New Zealand farmers look for practical ways to maintain production while improving nutrient efficiency. Further replicated research is required, but this represents a promising direction for future field programmes.
The next stage of EMNZ research
Publication is not the end of this work. It provides a stronger foundation for the next stage of the EMNZ research programme.
Current and planned work includes:
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independently assessed lucerne trials;
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commercial dairy pasture programmes under different nitrogen regimes;
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further investigation of Plant-Stim in pasture and forage systems;
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clover growth, root development and nodulation assessments;
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additional replicated crop trials across New Zealand growing conditions.
Our objective is to keep building a practical and transparent evidence base around biological agriculture—identifying where these programmes provide value, where responses are variable and how they can be used most effectively within commercial farming systems.
Thank you to everyone involved
This publication reflects years of product development, field observations, trial work and data collection.
We would like to thank the growers, contractors, advisers, researchers and members of the EMNZ team who helped make the work possible. Commercial field research depends on people being prepared to test new approaches, collect meaningful information and share the resulting experience.
We are extremely proud to see New Zealand field research published internationally and available openly to the wider agricultural community.
Read the complete open-access paper:
Paul Daly and Mike Daly, Archives of Agronomy and Soil Science, published online 24 September 2026.
