Agricultural biostimulants comprise a wide range of materials which aim to stimulate natural plant processes to boost crop health, enhance tolerance to environmental stresses and ultimately improve performance. And it appears that they really can work.
Scientific understanding of the whole plant and soil microbiome has advanced rapidly in recent years, so researchers can now identify the impact of certain active ingredients at different crop growth stages.
Near the quaint village of Brehan in Brittany, France, is a state-of-the-art laboratory and processing facility, where the Olmix Group has invested tens of millions of euros into algae research and innovation.
There are more than 9,800 species of seaweed, and many elements in them – like sulphated polysaccharides – are not present in land plants, which is what makes them so useful, explains Maria Matard-Mann, research projects manager at Olmix. “As crops don’t recognise marine sulphated polysaccharides they respond with immune aggression, which improves their resistance to stress or disease.”
As crops don’t recognise marine sulphated polysaccharides they respond with immune aggression, which improves their resistance to stress or disease.
Combined with micronutrients, inorganic acids, or clay, the products can be foliar or soil applications, used at different growth stages for maximum effect. “Algal hormones stimulate root growth and nutrient absorption, while biological activators boost humification in the soil. The aim is to complement crop and soil health, combining nutritional and biological activity.”
According to Chris Gamble, commercial and strategy manager at Micromix Olmix, there are four key types of biostimulant, and it’s important to use the right one at the right time – there is no one-size fits all. The first are seaweed-based, as produced at Brehan. The second are amino acids, which can be plant or animal based, and which influence the carbon and nitrogen cycle.
Humic and fulvic acids make up the third – these are very biologically active products from the natural breakdown of plants and animals. Finally, there are biologicals – a range of micro-organisms like rhizobacteria, which can be added to improve the biota of the soil.
The algae is pulped before processing.
Freshly harvested seaweed is washed to remove contaminants.
Chemical fractions are taken for scientific testing.
Scientifically sound advice
“You can combine any or all of the above,” says Mr Gamble. “But like all chemicals their combination can be synergistic or antagonistic, so it’s important to use an adviser who has a genuine scientific understanding of what you’re trying to achieve.”
It’s about working in harmony with the microbiome and other nutrients or plant protection products – it’s all interlinked.
For best results biostimulants should be used in conjunction with soil and plant tissue testing, he adds. “It’s about working in harmony with the microbiome and other nutrients or plant protection products – it’s all interlinked.”
Improving the soil
Traditional farming practices like ploughing and leaving soils bare have in many cases damaged the soil and depleted its valuable stores of organic matter. Biostimulants can help here, by stimulating soil biological activity and improving the breakdown of organic matter into humus.
Research with Litobratrice Farm in the Czech Republic has shown that treating soil with a humification activator boosted crop rooting, yields and soil water retention over several years.
Yield increase compared to control crop
|Spring wheat (2017)||18,7 %|
|Winter wheat (2018)||11 %|
|Winter OSR (2019)||23 %|
Regulating the industry
According to the European Biostimulants Industry Council, biostimulants are a critical to Europe’s sustainability, supporting agricultural and economic growth. However, they are still relatively new, so regulation is just catching up. By 2022 all biostimulants should be registered under new regulations helping recognise the role and influence of these products.