What is the role of zinc fertilizer for rice? Detailed explanation of application methods and precautions

Zinc is one of the essential trace elements for plants. China has many zinc-deficient soils, and applying zinc to zinc-deficient soil produces significant yield increases, with the effect being especially pronounced when zinc fertilizer is applied to rice. So what is the role of zinc fertilizer for rice? How should zinc fertilizer be used? What precautions are there?

What is the role of zinc fertilizer for rice?

1. It acts as a nutrient manager, playing a role in coordinating the distribution of nutrient elements within the crop, like the production team leader in rural areas in the past, allocating nitrogen, phosphorus and potassium to the parts of the crop that need them.

2. Zinc participates in the respiration of crops and plays a certain role in the normal growth and respiration of rice.

3. It enhances the stress resistance of crops, especially resistance to freezing and cold, and applying more zinc fertilizer prevents late spring cold damage in rice and improves high-temperature tolerance.

How should zinc fertilizer be used?

1. Zinc fertilizer should be applied to crops that are overly sensitive to zinc. Applying zinc fertilizer to corn, rice, peanuts, soybeans, sugar beet, kidney beans, fruit trees, tomatoes and so on gives better results.

2. Apply it on zinc-deficient soil: applying zinc fertilizer on zinc-deficient soil works well; do not apply zinc fertilizer on soil that is not zinc-deficient. If plants show zinc deficiency symptoms early on, it may be because the early spring temperature is low, microbial activity is weak, the fertilizer has not fully dissolved, the seedling root system is weak and its absorption capacity is poor; due to the phosphorus—zinc antagonism, and soil environmental influences, zinc deficiency may occur. But when the temperature rises later on, this symptom disappears.

3. Apply as a base fertilizer every other year: when zinc fertilizer is used as a base fertilizer, apply about 20—25 kg of zinc sulfate per hectare, spread it evenly, and apply it every other year, because zinc fertilizer has a long residual effect in the soil and does not need to be applied every year.

What precautions are there for using zinc fertilizer on rice?

1. It can only be applied to zinc-deficient rice fields. Generally, calcareous soil is rich in calcium, has a high pH value, and available zinc readily combines with carbonate or hydroxide to form zinc carbonate or zinc hydroxide precipitate and becomes unavailable, so it is often zinc-deficient; rice fields with strong reduction are prone to zinc deficiency; in rice fields where large amounts of nitrogen and phosphorus fertilizers have been applied for a long time, available zinc will also decrease. The above types of rice fields should be given more zinc fertilizer.

2. Apply an appropriate amount. For zinc fertilizer applied to rice fields, zinc sulfate is mostly used, generally 1-1.5 kg per mu. Because zinc fertilizer has an obvious residual effect, the zinc fertilizer applied in the first season still has a yield-increasing effect on the next season of rice, so zinc fertilizer does not need to be applied every year; generally it is applied once every 2-3 years.

3. Zinc fertilizer should be applied early. Applying zinc fertilizer in the seedling field gives high utilization and good results. It can be applied as a base application or as a spray. For field application, zinc fertilizer is best applied when the field is being harrowed.

4. Application should be even. To spread zinc fertilizer evenly, it can be mixed with physiologically acidic fertilizers. However, zinc fertilizer should not be mixed with phosphate fertilizer, so as to avoid forming zinc phosphate, which rice finds difficult to absorb and utilize, thereby reducing fertilizer efficiency.

5. The concentration for foliar spraying should be appropriate. Spraying zinc fertilizer as a foliar fertilizer is the main method of topdressing, and the suitable concentration is a 0.1%-0.2% zinc sulfate solution. In the seedling field, it is best sprayed at the 3-leaf stage of the seedlings and 3-5 days before transplanting. In the field, it is best sprayed after the seedlings have recovered from transplanting or 10-15 days after transplanting, preferably with 2-3 consecutive sprays.