How to scientifically apply nitrogen-fixing bacterial fertilizer?

Nitrogen-fixing bacteria fertilizer is a microbial fertilizer containing a large number of aerobic autotrophic nitrogen-fixing bacteria. Autogenous nitrogen-fixing bacteria do not coexist with higher plants and have no host choice, but live independently in soil, using organic matter in soil or organic matter secreted by roots as carbon source to fix nitrogen in the air or directly using inorganic nitrogen compounds in soil. Nitrogen-fixing bacteria are widely distributed in soil, and their distribution is mainly affected by organic matter content, pH value, soil moisture, soil maturity and available phosphorus, potassium and calcium content.

(1) Azotobacter is sensitive to soil pH, and its optimum pH is 7.0 ~ 7.5. When applying nitrogen-fixing bacterial fertilizer on acid soil, lime should be used in combination to improve nitrogen fixation efficiency. Overacid, overbased fertilizers or fungicidal pesticides should not be mixed with nitrogen-fixing bacteria fertilizers to avoid strong inhibition.

(2) Nitrogen-fixing bacteria have high requirements for soil moisture. When the soil moisture content is 25% ~ 40% of the maximum field capacity, they begin to grow, and when the soil moisture content is 60% ~ 70%, they grow best. Therefore, attention should be paid to soil moisture conditions when applying nitrogen-fixing bacterial fertilizer.

(3) Nitrogen-fixing bacteria are mesophilic bacteria, and the optimum growth temperature is 25 ~ 30℃. When it is lower than 10℃ or higher than 40℃, its growth will be inhibited. Therefore, nitrogen-fixing bacteria fertilizer should be stored in a cool place and keep a certain humidity to prevent exposure to the sun.

(4) Nitrogen-fixing bacteria can only play a full role in nitrogen fixation in an environment rich in carbohydrates and lacking in bound nitrogen. When the ratio of soil carbon to nitrogen is lower than 40 ~ 70 ∶ 1, the nitrogen fixation stops rapidly. The suitable ratio of carbon to nitrogen in soil is the most important condition for nitrogen-fixing bacteria to develop into dominant bacteria to fix nitrogen. Therefore, it is best to apply nitrogen-fixing bacteria or organic fertilizer on soil rich in organic matter.

(5) After applying a large amount of nitrogen fertilizer to the soil, apply nitrogen-fixing bacteria fertilizer every 10 day, otherwise the nitrogen-fixing ability of nitrogen-fixing bacteria will be reduced. The combined application of nitrogen-fixing bacteria with phosphorus, potassium and trace element fertilizers can promote the activity of nitrogen-fixing bacteria, especially in poor soil.

(6) Nitrogen-fixing bacterial fertilizer is suitable for all kinds of crops, especially Gramineae crops and leafy vegetables. Nitrogen-fixing bacteria fertilizer is generally used for seed dressing, mixed sowing, and then covered with soil to avoid direct sunlight. It can also be dipped in roots or used as a base fertilizer for vegetable seedbeds, or mixed with cotton seed fertilizer. It can also be applied to crop roots or combined with irrigation.