As Published in West Coast Nut Magazine

By Tom Gerecke

Biostimulant use increases resiliency in agriculture production. Biostimulants applied with proper nutrition can increase crop yields. In some cases, biostimulants can reduce fertilizer application rates while maintaining yields. Many growers are asking ”could my crop benefit from using a biostimulant?” According to Dr. Fred Below from the University of Illinois, “(Biostimulants) are here to stay and are going to be key management practices in our quest for high yields, but you better understand how they work and what they do…”

Biostimulant use has rapidly increased in worldwide agriculture over the last decade. The most rapid growth has been in Europe, in part to maintain yield levels with the loss of traditional inputs. The use of biostimulants in the US is lagging behind Europe, but also increasing rapidly. US growers spent $416.8 million in 2022 and are expected to increase their spend to $1.2 billion by 2026.

Biostimulants are a topic of much discussion, skepticism and even arguments in our industry. Consensus has not been reached over a technical definition, and the lack of specific regulations has allowed individual interpretations to flourish. The following definition is taken from the proposed US Biostimulant Act in Congress: a ‘plant biostimulant’ is a substance, micro-organism, or mixture thereof, that, when applied to seeds, plants, the rhizosphere, soil, or other growth media, acts to support a plant’s natural processes independent of the biostimulant’s nutrient content, thereby improving nutrient availability, uptake or use efficiency, tolerance to abiotic stress, and consequent growth, development, quality, or yield. Micro-organisms which act as biopesticides are excluded from the biostimulant definition. Microbial inoculants that act as biofertilizers are often indirectly included in many biostimulants definitions.

Lack of specific regulations creates labeling difficulties for many companies and products. There are no federal regulations for these products yet, let alone a standardized definition. To legally make verified performance result claims for most biostimulant products, the materials would need to go through the FIFRA PGR registration process. Consequently, most products with biostimulant components are registered as simple fertilizer products or non-nutritive plant and soil products with few claims of added performance. This is especially true on the West Coast. If governmental regulators decide biostimulants require FIFRA labeling, this will present an enormous barrier to market entry and stifle innovation, which could set the industry back a decade or more.

In a 2015 publication, Drs. Patrick Brown and Sebastian Saa proposed 2 general means of activity for biostimulants. The first way is a microbiome mode, whereby microbes in the environment have beneficial effects on crop growth primarily by modulating plant response to stress (biostimulants have been demonstrated to favorably alter the plant microbiome). Second is stress relief mode, whereby abiotic stress redirects plant growth resources toward survival mechanisms. As a consequence of prevalent crop stress, crop yields rarely reach their full potential. Many biostimulants enable plants to respond more effectively to stress. The following is a general list of major abiotic stressors:

  • Excessive heat and cold
  • Saturated soil and dry soil
  • Intense UV light
  • Excessive wind
  • Soil salinity
  • Soil compaction
  • Nutrient deficiency and toxicity

Following the Stress Hypothesis above, “plants constantly act to balance growth with the need for survival. The perception of stress results in an immediate reallocation of energy to defensive strategies that compromise yield,” according to Plant Physiology and Development (2015 Sinauer & Assoc). Since abiotic stress occurs in all environments, crop yield rarely reaches full potential. The encountered stress is rarely singular. Instead, multiple stresses occur together, such as drought and heat, or salinity and moisture stress. Biostimulants enable plants to respond more effectively to stress or alter normal plant metabolic limitations to productivity. Some means by which this is accomplished are:

  1. Improved nutrient availability – less energy is utilized for nutrient uptake.
  2. Higher nutrient use efficiency – improved growth under less nutrient load.
  3. Stress tolerance – increased antioxidant production, enzyme activities and plant hormone production.
  4. Specific physiological/genetic responses – e.g., photosynthetic rate increase, hormonal changes for growth, flowering and fruit set.

Biostimulant products are often formulated with multiple modes of activity. Dr. Gabriel Krouk has stated “combinations of molecules in biostimulants can have dramatically different effects on gene expression and/or physiological plant response.”  For full response, plants require adequate nutritional and carbohydrate building blocks. An application of biostimulants often exhibits responses that cannot be identified simply through the functions of the individual components, or “the system is more than the sum of its component parts” (Dr. Christopher Johnson, 2006). If ideal environmental conditions are guaranteed, there is less need for biostimulants.

Many categorizations of biostimulants can be found in popular and scientific literature. Broad categorizations can be difficult to understand, so the following is a practical list with examples. Don’t forget commercial products often contain a combination of materials, which take advantage of beneficial interactions among components, such as seaweed extract and amino acids.

  1. Humic Substances, Natural Organic Matter Extracts
    • Humic and fulvic acids, tannins, phenolics, compost tea
  2. Seaweed and Botanical Extracts
    • Seaweed, algae and plant extracts
  3. Inorganic Salts
    • Silicon, cobalt, phosphite (“non-essential nutrients” for plants)
  4. Beneficial Microorganisms
    • Mycorrhizae, beneficial bacteria, fungi and their by-products/extracts
  5. Chitosan, Chitan and other Biopolymers
    • Shellfish extracts, synthetic polymers
  6. Protein Hydrolysates, N Containing Compounds
    • Amino acids, peptides, organic N substances (betaines, polyamines)

Biostimulants are an essential component within the Nutrient TECH™ product portfolio. We have developed a number of proven biostimulant products with established technologies, such as ROOTERRA™, Amylis, N-Leaf, Ful Strength™, and NexxGen™. All of these products have established performance records in Europe and have demonstrated improved plant growth in California field trials.

Our flagship product, ROOTERRA, contains synergistic natural compounds, trace elements, and essential nutrients to promote the rapid establishment of new plantings and reduce environmental stress impacts. This combination of ingredients stimulates root development, plant vigor, stress tolerance and crop growth to maximize yields and quality. Field research with ROOTERRA has confirmed positive yield responses in a broad array of crops including nut trees, grapes and a wide array of small fruits, vegetables and field crops.

Amylis and N-Leaf are non-nutritive bacterial products which stabilize plant nitrogen status for crop growth. Research has demonstrated each of these materials can supplement growth at an intensity similar to 25-30 lbs. of nitrogen. They display additive effects when applied together. These materials are applied to soil and foliage respectively and fit both conventional and organic production practices.

Ful Strength is a unique fermented plant extract, high in fulvic acid, interactive natural compounds and essential plant nutrients. These ingredients encourage plant nutrient availability and uptake, soil biological activity and root growth. Initial California field research has demonstrated improved soil microbial response and crop yield, making Ful Strength an excellent addition to organic production systems.

NexxGen contains beneficial natural organic compounds, essential nutrients and valuable trace elements. These ingredients stimulate photosynthesis, refine nitrogen metabolism, and improve stress tolerance and rooting. Our initial California field research has demonstrated improved fruit set resulting in increased yield.

The prevalence of environmental stress in all our fields raises the question “could my crop benefit from a biostimulant?” Understanding biostimulants and product options will help increase confidence during the decision-making process. Product application and follow-up on crop response will provide in-field validation of benefits and allow localized adjustments for best use.

About Nutrient TECH

Nutrient TECH focuses on the development and marketing of advanced plant nutrition products and BioSolutions for agriculture in North America. Nutrient TECH continually strives to improve its production and QC/lab support for its advanced foliar nutrition and BioSolutions platform to consistently meet and exceed the exacting demands of today’s quality-conscious growers. Based in Dinuba, California, Nutrient TECH was founded in 1986 and was purchased by the De Sangosse Group in December 2015.

About De Sangosse

The De Sangosse Group, based in Agen, France, is a major international player in BioSolutions for crop protection and crop nutrition as well as for pest control. De Sangosse has been awarded the “Committed to CSR” label by AFNOR. Overall, the company has 975 employees, 26 operating companies and distribution activities in over 60 countries. The group’s mission is to bring about a major transformation in the agricultural industry through BioSolutions, thanks to dedicated investments and fruit of its R&D efforts, technical development, registrations and several strategic partnerships and make them available for all types of agriculture and all means of cultivation. The cross synergy of these technologies can Nourish, Boost and Protect crops for a three-way economic, social and ecological performance. The group’s aim is to develop, manufacture and market biofertilizers, biostimulants, biocontrol solutions, adjuvants and services to meet food needs, climate risks and environmental challenges, and to comply with regulatory changes in Europe and the rest of the world. De Sangosse contributes to creating value for its customers and the industry through innovation and by offering an elevated level of expertise. De Sangosse’s share capital comes mostly from its employees, thus guaranteeing its independence and ensuring a long-term vision of its business plan.