4 July 2022

Agricultural biostimulants: advances and perspectives

bioestimulantes agricolas

Agricultural biostimulants are products that maximize biological efficiencies. Biostimulants are also known as, plant supplements, plant strengtheners and conditioners, phytostimulants, bioactivators, bioactive compounds, and even soil, yield, crop, and plant enhancers.

Agricultural biostimulants reduce the need for fertilizers maintaining the good performance of the plant’s vital processes and allowing high yields and good quality products. The three main functions of biostimulants applied to plants are: to enhance nutrition efficiency, to increase abiotic stress tolerance and to improve plant quality traits, regardless of its nutrient contents.

Agricultural biostimulant functions

Biostimulants have been shown to act on many factors affecting plant growth, such as root growth, root diameter, soil water holding capacity, increased microbial activity leading to increased nutrient availability and many more. However, most of the time the responses are highly variable. They depend on climate, soil type, organic matter content, tillage system and type of crop rotation.

Agricultural biostimulants vs biofertilizers

A biostimulant is a product that helps enhance the plant’s growth. It does not serve nutrient deficiency. Instead, it increases nutrient availability, water holding capacity, metabolism, and chlorophyll production. According to the AEFA (Spanish Association of Agronutrients Manufacturers) biostimulants are defined as those active substances that aim to improve the plant’s nutrient adsorption mechanisms, while fertilizers are those active substances that aim to provide nutrients to plants.

Biofertilizers also differ from biostimulants in the fact that they do not improve tolerance to biotic stress (where plant cannot sustain its normal growth due to the interaction with deleterious microorganisms – fungi, bacteria, viruses, viroids, phytoplasma, and nematodes).

Advantages of the use of agricultural biostimulants

Biostimulants are natural crop enhancers. This fact implicitly indicates the great advantage that this type of substance offers us: the decrease in the massive use of fertilizers, replacing them with biostimulants. Among the advantages offered by biostimulants, we can highlight:

  • Increased nutrient and water assimilation, translocation, and use.
  • Augmented efficiency of the plant’s metabolism
  • Boosted Root and Plant Growth
  • Enhanced plant tolerance to and in the recovery from abiotic stress (extreme temperatures, drought, flood, high winds, nutrient deficiency, soil compaction)
  • Improved Plant Performance, Quality, and Yields
  • Ameliorated Soil Health, Function, and Performance
  • Strengthened Resistance to Pathogens

Scientific research on types of biostimulants

Research in the biostimulants sector has experienced a strong and progressive increase in the number of publications in recent years and in 2021, the number of publications has increased even more, reaching more than 450 papers published at international level. Analyzing the breakdown of articles by biostimulant substance, it is observed that plant extracts and algae have been the most studied, followed by humic substances, protein hydrolysates, microalgae and silicon. In contrast, in the case of microbial biostimulants, most studies have focused on nitrogen-fixing microorganisms, which are gaining interest, as they can help reduce the amount of nitrogen fertilizers, now that there is a shortage of raw materials, very high prices and increasing attention to both environmental and economic sustainability.

bioestimulante agricola

Research activity on the effects of biostimulants in 2021 has focused especially on abiotic stress resistance, followed by improved nutrient uptake and then improved product quality. Among abiotic stresses, drought is the most studied, followed by salinity and temperature extremes. While the most studied nutrient last year was nitrogen, the element required, after carbon, in the greatest quantity by plants for their growth and development. A breakdown of the papers by crop shows that tomato is by far the leading crop by number of publications.

Tomato is followed by wheat and soybean. Finally, the subdivision of the articles according to the method of application shows an increased interest in seed treatment with biostimulants, which represents a valid, biological and alternative solution to chemical coating agents.

Agricultural biostimulants market

Biostimulants are becoming increasingly popular. The global biostimulants market reached $3.5 billion in 2021, up 11.3% from 2020. Growth from 2021 to 2025 is forecast to be 11.6%, according to bio-based agricultural market research firm DunhamTrimmer. Asia-Pacific and Latin America are outpacing the rest of the world in biostimulant growth, increasing 12.5% and 12.7%, respectively, driven by the regions’ relatively late adoption and room for growth, consumers’ increasing willingness to pay for higher-quality agricultural products, and the need for more efficient use of resources. Brazil, China and India also present significant market opportunities.

The organic food industry, which is growing at a healthy pace, is the main driving force behind the growth of the biostimulants market. Increasing awareness among farmers about the benefits of biostimulants is another factor augmenting market growth. The market is also growing due to increasing adoption of sustainable farming methods. Political and government backing for more sustainable farming technologies is also driving the biostimulants market: the Farm to Fork strategy, which has set targets such as reducing fertilizer use by at least 20% by 2030, is at the heart of the European Union’s Green Deal and is a clear example that support for biostimulants is set to gain traction.

Agricultural biostimulants BOOM of 2022

Agriculture is dealing with two opposing forces. On the one hand, more production is needed due to world population growth. On the other, we are witnessing a necessary reduction in the amount of available crop productivity tools due to government regulations such as the EU Green Deal. In addition, climate change is also putting a strain on cropping systems.

Whether it’s too dry or too wet, we’re seeing these extremes all over the world. In this complex situation, there is a growing demand for new tools that are sustainable, effective and affordable to complement synthetic chemistry: it’s a big global opportunity for biostimulants.  For many years, and still today, biostimulants have been considered something nice to apply, but not essential. It was assumed that with rising input costs, they would have been the first to be cut, but trends seem to be going in the opposite direction. The most prominent product category? Nitrogen-fixing bacteria for non-legume crops is booming in the United States, the only exception to the faster growth in Latin America and Asia-Pacific.