What exactly is biostimulant? Is it a hormone?

Time:2022-11-08

Preface: Before a customer feedback such a question, how can your product ingredients contain stimulants? Isn't your product organic fertilizer? How can you add hormones?

 

Nowadays, advocating green, organic, non-polluting agriculture, I believe that many people see the word "hormone", the heart can not help but tighten, worrying about the residue, harmful to health.

Therefore, biostimulants in the end is not a hormone? Will there be residues, harmful to health? Today, I will take you to understand and learn together.

 

1. Definition of biostimulants

Macro, biostimulants are a series of organic compounds, inorganic compounds or microbial products that can improve the nutritional and health status of crops, improve the utilization of pesticides and fertilizers, stimulate the natural physiological processes of crops, act on plants, seeds or soil, improve crop resistance, and ultimately increase crop yields and improve quality. Microscopically, biostimulants are a series of organic or inorganic molecules that affect the level of gene expression, thereby regulating biochemical and signaling processes, and influencing the metabolism of nutrients, water and assimilated products.

 

2. Main types of biostimulants

There are many types of biostimulant products on the market today, and new biostimulant products are constantly emerging.

Based on the type of substance or source, biostimulant products can be categorized into microbial preparations and their extracts, protein hydrolysis products, humic acids, algae and plant extracts, inorganic and synthetic products. Comparison of the properties of plant growth regulators and biostimulants

 

3. Difference between biostimulants and hormones

Gao Xiangzhao, the chief expert of National Agricultural Technology Extension Service Center of the Ministry of Agriculture, said that biostimulants have been used in China for a long time, which is different from hormones, and there is a significant difference between the two.

First of all, bio-hormones are inherent in crops and can be synthesized by themselves, while hormones are usually processed using certain production processes; secondly, biostimulant products can indirectly promote plant growth, and usually overuse will not cause too much harm, while hormone products will cause great harm if they are not used properly. There are significant differences between the two, and it is not appropriate to explain biostimulants using the existing concept of hormones.

 

The following points can help you better understand what biostimulants are:

● Biostimulants are derived from naturally occurring in nature, rich in certain active substances, not synthesized by artificial chemicals, and can act directly on the plant body. Examples are the familiar seaweed extracts, humic acids and amino acids.

● Since they are organic products, they do not produce undesired residues on plants and do not alter the genetic characteristics of crops and harvests. Such substances do not cause any harmful effects on humans, animals and the environment.

● Biostimulants do not act directly on the plant, but through an indirect conversion effect, they stimulate the plant itself for uptake and defense, and also stimulate the development of beneficial organisms in the soil.

 

4. Functions of biostimulants

Biostimulants have a multifaceted role in crop growth, although it is not a fertilizer or pesticide, but has the function of fertilizer or pesticide, in promoting crop growth, enhance crop resistance to adversity stress has an important role.

The target of biostimulants is the crop itself, a small amount of application can achieve the effect of promoting plant growth and development, and this promotion is difficult to achieve the traditional nutrients.

The target of biostimulants is the crop itself and the soil environment, mainly through a variety of ways to act on the crop from seed germination to the maturity of the entire life cycle of harvest. Compared with traditional chemical pesticides and fertilizers, the functions of biostimulants are quite different. According to the relevant literature, their main functions are summarized in the following five points:

① Promote plant growth by enhancing nutrient absorption and transportation;

② Improve plant disease resistance and stress tolerance by enhancing plant immunity;

③ To regulate and improve the water balance in plants;

④ Regulating and improving the water balance in plants; Improving the physical and chemical properties of the soil, protecting and improving the soil, and promoting the growth of beneficial microorganisms in the soil;

⑤ Improve the physical and chemical properties of the soil, protect and improve the soil, and promote the growth of beneficial microorganisms in the soil.

 

It is worth noting that the functions of plant biostimulants are similar to, but different from, the traditional concept of plant growth regulators, and the table above specifies the differences between these two types of substances. Biostimulants come from a wider range of sources and have more diverse functions than plant growth regulators. Plant biostimulants act not only on the plant but also on the soil and soil microorganisms. More importantly, biostimulants enhance the metabolic processes of the plant without altering the original metabolic pathways of the plant.

 

5. Application of biostimulants

At present, Qingdao Sapphire has launched biostimulant products, such as seaweed extract series products: seaweed extract, seaweed polysaccharide, alginate oligosaccharide; chitosan oligosaccharide and fish protein and so on.

 

Seaweed extract through the regulation of crop metabolism and physiological functions, promote crop root growth, increase biomass and thus improve crop yields, can alleviate pests and diseases, prevent frost and drought and other abiotic adversities, the quality of crops also has a certain role in improving seaweed extract by improving the inter-root soil environment of plants to promote plant growth. Such as alginate applied to the soil can form humic clay complex, enhance the stability of soil aggregates and soil permeability, the improvement of the stability of the aggregates can directly promote the absorption of nutrients in crops. Alginate polysaccharides can also affect the distribution of inter-root microbiota, stimulate the beneficial bacteria in the soil to better act on the plant and inhibit the proliferation of pathogenic microorganisms. Similar to humic acid, seaweed acid extract contains a large number of polyanionic compounds, which can chelate heavy metal cations in the soil and play a role in remediation of heavy metal contaminated soil.


Seaweed extract acts as a biostimulant to directly stimulate plant growth and development. By enhancing the accumulation of nitrate reductase and phosphatase in the roots of plants, it enhances the absorption of mineral nutrients, increases the chlorophyll content, enhances the efficiency of photosynthesis, improves the ability of plants to resist various environmental stresses and pests and diseases, and increases crop yields.


The prevention and control mechanism of biostimulants against viruses, bacteria and fungi: one is to directly inhibit their reproduction and growth; the other is to induce crops to activate the relevant defense mechanisms. For example, in Zhang Yunhong's study, the disease prevention mechanism of seaweed extracts against cytomegalovirus (CMV) is manifested in in vitro passivation, inhibition of viral proliferation, enhancement of protective enzyme activity, and enhancement of plant resistance, etc. Chitin and its derivatives have been shown to be effective against plant diseases. Chitin and its derivatives have a certain inhibitory effect on plant pathogens and fungi, and can also induce the production of resistance proteins and phenolic substances, induce lignification of infested spots, and strengthen the cell wall, so that the plant has a broad-spectrum resistance.