Q: What is microbial fertilizer (bio-fertilizer or bacterial fertilizer)? What are the quality requirements for the product?
A: Microbial fertilizer, also known as bio-fertilizer or bacterial fertilizer, is a type of agricultural input that contains beneficial microorganisms. These microbes help improve soil fertility and enhance plant growth through their biological activities. Common beneficial microorganisms include rhizobia, which fix atmospheric nitrogen; phosphate-solubilizing bacteria, which release insoluble phosphorus in the soil; and potassium-solubilizing bacteria, which help release mineral potassium. Other types include antibiotic-producing bacteria like "5406," which suppress harmful pathogens and stimulate plant growth, and enzyme-producing bacteria that aid in breaking down organic matter. The effectiveness of microbial fertilizers depends not only on the microorganisms themselves but also on the medium they are applied in, which supports their activity.
As an agricultural product, microbial fertilizer must meet specific quality standards. According to the Chinese standard NY227-94, it should have a certain number of viable microorganisms, a low level of impurities, and a clear expiration date. In addition to pure microbial agents, there are also composite microbial fertilizers and bio-organic fertilizers. Composite microbial fertilizers combine specific microorganisms with nutrients to provide, maintain, or improve plant nutrition. According to NG/T798-2004, the total nutrient content (N+P2O5+K2O) of different forms—liquid, powder, granules—should be no less than 4%, 6%, and 6% respectively, though higher levels may inhibit microbial activity. Bio-organic fertilizers are made by combining organic materials with beneficial microorganisms, promoting both microbial activity and organic matter decomposition. According to NY884-2004, these fertilizers must contain at least 25% organic matter.
Q: How to use microbial fertilizer reasonably? A: Microbial fertilizer can be applied as base fertilizer, top dressing, or directly into planting holes. It can also be used for seed coating, soaking, root dipping, or foliar application, depending on the product type. For example, solid bacterial fertilizers can be mixed with decomposed organic manure (2 kg of bacteria + 40–60 kg of compost) for base fertilizer or seedling treatment. When preparing seedlings, seeds can be soaked in a 10–20 times diluted solution before sowing. Similarly, seedlings can be dipped in the same solution before transplanting. Root dipping solutions can be diluted 100 times, while foliar sprays require a 500-fold dilution.
Compound microbial fertilizers are typically applied at 10–20 kg per mu as base or top dressing, and foliar applications should follow product instructions. Bio-organic fertilizers are best used as base fertilizer at around 100 kg per mu, often combined with farmyard manure. Top dressing should be reduced and applied 7–10 days earlier. It's important to note that high levels of NPK fertilizers or excessive nitrogen can reduce the effectiveness of rhizobium, phosphate-solubilizing, and potassium-solubilizing bacteria. Additionally, microbial fertilizers should not be mixed with pesticides, chemical fertilizers, or strong acids/alkalis during storage, as this can kill the beneficial microorganisms.
Q: What is carbon dioxide fertilizer? How do greenhouse vegetables get carbon dioxide?
A: Carbon dioxide (CO₂) is a key component of air and essential for photosynthesis. In greenhouses, CO₂ levels often drop below optimal ranges (typically 800–1000 mg/L), especially when crops are dense and ventilation is limited. When CO₂ concentrations fall below 80–100 mg/L, plant growth can be severely restricted. To address this, farmers often apply carbon dioxide fertilizer, also known as gas fertilizer. This can be done through natural methods like proper ventilation, organic fertilizer application, and balanced nitrogen use, or through artificial CO₂ enrichment.
Common methods for generating COâ‚‚ in greenhouses include chemical reactions and biological techniques. One simple chemical method involves mixing ammonium bicarbonate with diluted sulfuric acid in plastic buckets. Each bucket is filled with 1 part of diluted sulfuric acid (1:3 ratio of concentrated acid to water) and 1 part of ammonium bicarbonate. The reaction produces COâ‚‚ gas, which is then released into the greenhouse. This method is cost-effective and easy to implement, but safety precautions must be followed.
Q: How to properly apply carbon dioxide fertilizer?
A: Commercial COâ‚‚ fertilizers come in three main forms: solid, liquid, and gaseous. Solid fertilizers include dry ice and granules. Dry ice sublimates into COâ‚‚ at room temperature and is ideal for crop absorption. However, it is expensive and difficult to handle. Granules can be sprinkled on the ground or buried in the soil, releasing COâ‚‚ after absorbing moisture. One application can last up to 40 days, with about 40 kg used per area.
Liquid CO₂ fertilizers involve using a pressurized cylinder connected to a hose system. Holes are made every 3 mm along the hose, and the diameter increases from the source outward to ensure even distribution under the greenhouse film. The pressure should be maintained between 1–1.2 kg/m², and CO₂ should be released for 6–12 minutes daily.
Gaseous CO₂ fertilizers, such as double-microbial products, use fermentation by microorganisms to produce CO₂. These are practical and low-cost, with one capsule per square meter and a depth of 3 cm. They work best in soils with 80% humidity and temperatures above 15°C, releasing CO₂ for over 30 days with a recommended application rate of 6.7 kg per mu.
Globe Valve,Brass flange stop valve,Brass Globe Valve
Chongqing Xingjida Import and Export Trade Co., Ltd. , https://www.xjdvalve.com