The search for naturally occurring highly active biostimulants

At the heart of Maxstim is a passion to drive research, development and innovation towards a more sustainable way to practice agriculture, horticulture and turf management. Over recent years our CEO Richard Salvage has been on a mission to continue to improve the effectiveness of the complex biostimulants we manufacture. Having clearly identified that bioflavonoids and polyphenols are important bioactive components, he has now created a unique range of highly effective biostimulants. Alongside this, Maxstim has honed specific production techniques which increase, optimise and harness the abundance of these bioactive compounds. These are being patent protected and have been named AmphenoxTM.

This exciting development heralds a new era of biostimulants. We can demonstrate that AmphenoxTM is rich in secondary metabolites and highly active bioflavonoids which enable plants to turbocharge their immune systems and stimulate essential biochemical metabolic processes influencing key functions such as growth, chlorophyll production, root development and stress management.

In the technical paper we have released we share detailed insight in to how we have evaluated AmphenoxTM, the results and our methodology for creating some of our products.

The importance of data in assessing the efficacy of biostimulants

Background: As the need for biostimulants becomes better understood and their place in the armoury of agronomists more established, creating a credible means of generating and assessing their use and efficacy becomes more important. Maxstim Ltd is a leader in biostimulant design and manufacture and understands the need to demonstrate the integrity and quality of the supporting data that underpins the performance of our products. 

This document describes in detail how our product development and technical team carry out the assessment of product performance and how the efficacy data is generated and assessed for quality and reporting. At the same time recognising that having solid data on product effects is irrelevant if it makes no contribution to real farmer/grower value. 

Maxstim procedures for supporting biostimulant claims 

In order to enable access to the European Union single market, CE marking is required for all fertilising products (the definition of which now includes biostimulants). 

This is covered by Regulation (EU) 2019/1009 FPR published in July 2019 and which will be fully operational in July 2022. 

The European Biostimulant Industry Council (EBIC) have developed some guidance to follow when justifying plant biostimulant claims. These principles are expected to be incorporated into harmonized European standards currently being developed by the European Committee for Standardization (CEN) to support the implementation of the regulation (Ricci et al., 2019; General principles to justify plant biostimulant claims. Frontiers in Plant Science Volume 10, article 494). 

Maxstim has adopted these procedures for evidencing biostimulant claims. These are based on the EU definition of biostimulants: 

An EU fertilising product the function of which is to stimulate plant nutrition processes independently of the product’s nutrient content with the sole aim of improving one or more of the following characteristics of the plant or the plant rhizosphere:
(a) nutrient use efficiency
(b) tolerance to abiotic stress
(c) quality traits
(d) availability of confined nutrients in the soil or rhizosphere
(e) yield improvement (yield increase or yield security) 

Note that the effects of biotic stress cannot be entirely separated from abiotic stress. Consequently, reducing abiotic stress can have an indirect effect on the impact of pests and diseases on crop plants. 

Plant Biostimulants “shall have effects that are claimed on the label” 

  • A conformity assessment dossier will be compiled for Maxstim products and include evidence of the product’s effects 
  • Harmonized European Standards will indicate what constitutes compelling evidence 

Underlying Principles to Justify a Biostimulant Claim: Data 

  • Existing data (pre Regulation 2019/1009 FPR) can be used 
  • Existing data sets and new data should comply with acceptable Experimental Quality Criteria (this can be generated by the manufacturer, independent researchers, distributors or growers) 
  • Data should have agronomic relevance (i.e. yield improvement, must demonstrate a biologically relevant agronomic trend) 

Data should be of sufficient quality to support any claim: 

To assess data quality a Klimisch score (Klimisch et al., 1997) can be used to evaluate data robustness. Scores of 1 and 2 are acceptable, though data with scores of 3 and 4 can be used as part of a wider assessment e.g. supporting observations of consistent “agronomically” positive data trends (i.e., not necessarily statistically significant) compared to untreated plots in field trials. 

Learning to use biostimulants in turf management

Richard Salvage and Colin Fleming

School of Biological Sciences, Queen’s University of Belfast, 19 Chlorine Gardens, Belfast BT9 5DL, UK
Maxstim. Elm House, Tanshire Park, Elstead, Surrey GU8 6LB


Turfgrasses have mechanisms to withstand biotic and abiotic stress
Like all plants, turfgrasses have evolved ways to help them tolerate and survive the wide range of stresses that can limit their growth. These stresses include attack by fungi, bacteria, viruses, insects and nematodes (biotic factors). Plants also have adaptations which help them to counter environmental stresses such as heat, cold, drought, waterlogging and high salinity (abiotic factors).

The source of a plant’s ability to minimise damage by such a wide range of biotic and abiotic factors is found in its DNA. Located inside the plant cells, chromosomes contain tens of thousands of genes which carry the genetic codes for manufacturing proteins (e.g. enzymes and the structural proteins used to build the various parts of the plant) and small RNA molecules which help control the complex genetic/metabolic processes required for normal plant functions. In a healthy plant, multiple interconnected biochemical pathways respond to internal and external signals to ensure that the plant can carry out normal processes such as germination, root and shoot growth, photosynthesis, respiration and seed production. Many of these pathways also regulate plant defence against pests, pathogens and abiotic stresses. Plant scientists have been investigating how plants use these biochemical pathways to minimise stress damage and they have also identified hundreds of plant chemicals involved in stress resistance.

How do plants protect themselves?
Plants use physical and chemical barriers to prevent pathogen entry and infection. There are also a wide variety of inducible defence mechanisms that are triggered upon pathogen or abiotic stress detection. These inducible defences include molecular, biochemical, and morphological changes, oxidative burst, expression of defence-related genes, production of antimicrobial compounds, and targeted cell death which localises infection sites preventing disease spread.

Major components of the regulatory networks controlling plant defence include intra cellular signalling and plant hormones. Recent genetic studies have demonstrated that these systems are involved in both abiotic and biotic stress responses, indicating convergence of the pathways and the existence of a general stress response in plants. This is confirmed by the many examples of abiotic stress (e.g. salinity and drought) increasing plant susceptibility to subsequent disease. Similarly, plant responses to abiotic stress can be influenced by previous pathogen infection, which has been shown to reduce photosynthesis and water use efficiency and induce abnormal stomata opening patterns, all of these being critical for plant tolerance to abiotic stress.

Plant hormone pathways are key among these defence systems and include auxins, gibberellins (GA), abscisic acid (ABA), cytokinins (CK), salicylic acid (SA), ethylene (ET), jasmonic acid (JA), brassinosteroids (BR) and peptide hormones.

SA, JA and ET, have roles in regulating plant defence responses against pathogens and pests as well as abiotic stresses. In particular, SA plays a crucial role in plant defence and is generally involved in the activation of defence responses against biotrophic pathogens (e.g. rusts which don’t normally kill the plant, but feed on living tissue). JA and ET are usually associated with defence against herbivorous insects and necrotrophic pathogens such as dollar spot (Sclerotinia) which cause extensive plant tissue death to access nutrients. While SA and JA/ET defence pathways are often mutually antagonistic, there is also evidence of synergy between SA and JA/ET.

Figure 1. Role of plant hormones in managing biotic and abiotic stress.

What is clear from recent research is that normal plant metabolism is disrupted by biotic or abiotic stress leading to significant effects on all aspects of plant growth. In the case of many pests and pathogens it has also been demonstrated that they can actively interfere with plant defence systems to facilitate their attack and infection.

Biostimulants can help manage pests, diseases and abiotic stress

Turf managers are currently faced with the “perfect storm” of increased pest and disease issues, more frequent occurrences of extreme weather (both often resulting from climate change) and restrictions in the use of plant protection products. Following major advances in the development of effective biostimulants for agriculture and horticulture, increasingly our industry is turning to these products for solutions to these problems.

In Europe, biostimulants have been defined as ‘materials containing substance(s) and/or microorganisms whose function, when applied to plants or the rhizosphere, is to stimulate natural processes to enhance/benefit nutrient uptake, nutrient efficiency, tolerance to abiotic stress and crop quality.’ There are currently discussions on extending this definition to include the stimulation of plant tolerance to pest and pathogen attack. Regardless of these considerations, a range of materials can act as biostimulants (Table 1). Over 85% of the commercially available products are from three basic sources; peat, amino acids and seaweed and they tend to be single source or single component solutions to very complex plant x stress interactions.

Table 1: Major groups of biostimulants and some of their effects on plants

Different biostimulants induce distinct plant responses, consequently new and innovative formulations have been developed incorporating a combination of bioactives which deliver multiple stimuli to the plant, improving growth and enhancing protection from an ever-increasing range of stressors (Plates 1 and 2).

Plate 1: Enhanced germination and growth in ryegrass turfgrass sprayed with a blend of biostimulants (Maxstim). (Untreated plants on the left, treated plants on the right)

Plate 2: Enhanced germination and growth in ryegrass turfgrass sprayed with silicon biostimulant (Cynosa). (Untreated plants on the right, treated plants on the left)

Priming turf for stress tolerance
Perhaps one of the most significant discoveries regarding biostimulants is their ability to predispose plants to deal more effectively with a future stress. Analogous to immunization, it has been demonstrated that pre-treatment with biostimulants can prime plants for more efficient activation of their cellular defence responses. This means that a primed turf will respond more quickly and strongly to, for example, drought stress or a pathogen infection. Importantly, it has been shown that when a plant is subjected to an abiotic stress or infection, activating a normal defence response involves major energy costs that often affect plant growth. These effects are significantly lower when a primed plant is stressed or infected and so the outcome for plant growth is improved.

Plate 3 shows creeping bentgrass primed with a seaweed extract responding better to drought stress.

Key to priming turfgrass in this way is that the biostimulant treatment is made before the stress is experienced, so the old adage of “little and often” provides guidance in how best to apply biostimulant as a stress preventative.

Plate 3: Response of creeping bentgrass to drought stress. SWE1 and SWE2 (sprayed with cold processed seaweed extracts) and nutrient only (no treatment).

A final point to make regarding use of biostimulants concerns expectations. Sometimes users are disappointed with the apparent lack of effect after biostimulant application. However, experience has shown that the most obvious responses to biostimulant treatment are seen in poorly performing turf or when a treated turf is impacted by disease or extreme environmental conditions. Increasingly farmers see biostimulants as a “biological insurance”, evidenced by the observation that they are the fastest growing sector in the agriculture market.

Increasingly, our industry has been embracing this technology, but the effective use these tools will require a better understanding of how and where they work as well as collaboration between researchers, producers and most importantly, end users. Clearly it can be much easier to define biostimulant action than to define a biostimulant and even though our industry may never share a common understanding and definition of biostimulants, it will be those organisations that focus on defining and gaining a clear understanding of biostimulant action who will be the industry leaders and innovators.

Written by: Richard Salvage (CEO at Maxstim) and Colin Fleming (Chief Scientific Officer at Maxstim).
Maxstim Limited has developed a reputation as a leader in plant biostimulant design and manufacture. Its growth is built on a robust scientific approach with an ambitious research and development programme.

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Maxstim achieves organic certification

The latest innovation is an organic formulation that will meet the stringent requirements to be certified by well-respected and globally renowned testing and accreditation facilities.

The organic farming market is set to increase significantly over the coming years. In Europe, the EU’s Biodiversity Strategy to 2030 is looking to set a target of 25% of all agricultural land in Europe to be farmed organically. This is alongside an additional goal of reducing the use of chemical pesticides by 50%.

Maxstim for Organic Agriculture, our new biostimulant formulation has achieved Ecocert accreditation. Almost 30 years ago the Ecocert certification was established to highlight environmentally friendly and socially conscious practices.

“Our business is striving to create a range of products which match the core values established by Ecocert. Our new formulations respect the natural environment, the protection of valuable resources and the impact we have on our planet. Challenges that cannot be ignored. We are really excited to have more organic formulas under development which will follow this sustainable path.”

We are currently completing the next accreditation to comply with American regulations, for the National Organic Program (NOP) certificate. The new Maxstim for Organics products will be available for distribution mid-March.

New CSO Appointment

As the role of biostimulants becomes more and more critical within amenities, agriculture and horticulture so does the need for continued research and development. Our growth and reputation in this field is built on a robust scientific approach with an ambitious research and development programme.

We are excited to announce that this has now been strengthened further through the appointment of Dr. Colin Fleming as our Chief Scientific Officer.

Colin’s reputation in agricultural and amenity circles comes from his ability to share and impart crucial knowledge and information that enables positive outcomes in a way that is easy to understand and to act on. Most people who have worked with Colin would use the word ‘generous’, not only to describe his willingness to share his wisdom but in his approach and the time he devotes to individuals and projects.

He is excited and looking forward to adding his intellectual weight to this innovative commercial proposition.

“I have been studying the management abiotic and biotic stresses in plants using biostimulants since 1989 and today I am delighted to have the opportunity to join the world leading Maxstim team and contribute to the development of novel solutions for growers and turfgrass managers.”

As a plant pathologist and a world renowned nematologist, Colin has worked with many of the most prestigious sports venues in Europe and beyond. He is the first person to be called by many of the UK’s Premiership football clubs and world class golf venues if there is a problem that his knowledge of turf matters can resolve.

With over 150 publications to his name he is recognised as one of the leading plant disease specialists in the UK. Graduating from Queen’s University, Belfast in Zoology and completing a PhD in Biological Sciences Colin spent some time researching in plant pathology at the University of Nebraska. More recently he has been a Principle Investigator at the Agri Food and Biosciences Institute and a senior lecturer at Queen’s University, Belfast. Working with DEFRA and the European Union, Colin has also been instrumental in contributing to plant disease protection policies creating food security for the UK.

We are delighted to welcome him to Maxstim and look forward to accelerating our exciting plans through 2021.