Abstract: Organic water-soluble fertilizer is one of the key areas in the development of New Fertilizers. It has the characteristics of good solubility, quick effect and high utilization rate. It can be used for foliar spraying and integrated application of water and fertilizer, and has great development potential in agricultural production. However, the registration of organic water-soluble fertilizers in China needs to meet the requirements of relevant laws and regulations of China fertilizer registration.

Definition

Organic water-soluble fertilizer is a new type of water-soluble, highly concentrated, multi-functional and nutritious fertilizer product, which is produced by extracting organic water-soluble raw materials (such as flavonoids, amino acids, alginate, sugar alcohols, chitin, sugars, organic acids, etc.) from organic waste materials after treatment, and could be compounded with macro-elements, medium elements or trace elements.

Features

1) Basing on organic nutrients, having various forms, fast fertilizer efficiency and high fertilizer efficiency utilization rate;

2) Having good water solubility, is suitable for fertilization methods of drop and sprinkling irrigation, and having the advantages of precise application, convenience, safety, labor saving, agricultural water saving and less pollution under integration with water and fertilizer.

Types of raw materials

The raw materials of organic water-soluble fertilizers currently registered in China mainly include the following types, and seaweed is the most:

1) Four major types of seaweeds: Brown algae (Laminaria japonica, Ascophyllum nodosum, Undaria pinnatifida, Scagassum), Blue-green algae (Stigonema, Microcystis, Spirulina), Green algae (Ulva pertusa, Monostroma, Codium), Red algae (Porphyra, Gelidium amansli , Gracilaria). Europe and the United States mostly use Ascophyllumnodosum and Fucus vesiculosus; South Africa uses King Algae, and China uses Sargassum, Macrocystis pyrifera, Laminaria japonica and Undaria pinnatifida;

2) Chitin from Shrimp shell and crab shell;

3) Molasses fermentation concentrate;

4) Low-value fish;

5) Other categories: Pomace, Corn steep liquor, soybean meal, etc.

Basic requirements

The production enterprise must have a stable source of raw materials, the performance of the raw materials is stable, and a long-term and stable supply agreement must be signed with the raw material supplier, the origin resources should be used safely and efficiently.

From a safety perspective, for imported products that use organic degradation as raw materials, the production materials and process technology should be scientifically evaluated, and products with unclear technical characteristics and low nutrient content will be restricted.

Technical specification

Organic matter; pH; water-insoluble matter, can add an appropriate amount of macro elements, medium elements, and trace elements.

The following requirements should be noted:

1) In order to ensure the application effect of organic water-soluble fertilizers, its main component should be organic matters, and the lowest limit of organic matter content should be set.

2) Organic water-soluble fertilizer with biological substances such as seaweed and chitin as main raw materials, the content of organic matter should be ≥5.0%（powder）, and the content of organic matter should be ≥50 g/L（aqueous solutions）.

3) For organic water-soluble fertilizers with molasses, low-value fish, yeast liquid, soybean meal as main raw materials, the content of organic matter should be ≥10.0%（powder）, and the content of organic matter should be ≥100 g/L（aqueous solutions）.

4) The detection method of organic matter adopts the NY 1976-2010 Water-soluble fertilizers-Determination of organic matter content.

5) For organic water-soluble fertilizers with molasses fermentation concentrate as the main raw material, the content of chloride ions and sodium ions in the product should be strictly controlled and should be clearly indicated on the product label.

Restricted registration of organic water-soluble fertilizer products

1) Overseas organic water-soluble fertilizers that use animal wastes and its fermentation broth as the main raw materials, have a risk of animal diseases and harmful organisms spreading into China

2) Products with complex raw materials, low production technology level, poor repeatability of product inspection results, and unstable product quality.

3) Products with unclear active ingredients, unclear functional mechanism, and simple blending

4) Products using weathered coal should apply for Water-soluble fertilizers containing humic-acids (NY 1106-2010) and using amino acids as the main raw materials should apply for Water-soluble fertilizers containing amino acids (NY 1429-2010).

Security requirements

1) Heavy metal limits: implement industry-standard NY/T 1980-2010 Fertilizers-Determination of mercury, arsenic, cadmium, lead and chromium content (Hg≤5 mg/Kg; As≤10 mg/Kg; Cd≤10 mg/Kg; Pb≤50 mg/Kg; Cr≤50 mg/Kg)

2) Toxicity test: implement industry standards NY/T 1980-2018 Fertilizers and soil amendments-Determination and evaluation of acute oral toxicity.