What is the law of eggplant fertilizer requirement? What problems should be paid attention to when fertilizing?

As one of the few purple vegetables, eggplant is deeply loved by consumers because of its rich nutrition, so it is widely planted in the north and south of China. So what is the law of fertilizer requirement for eggplant? What problems should be paid attention to when fertilizing? Today we are going to talk about fertilization of eggplant.

First, the law of eggplant fertilizer demand

Eggplant has a long picking period and high yield, and needs a lot of nutrients in the growth process, so it belongs to a fertilizer-loving and fertilizer-tolerant crop. Nitrogen fertilizer: 2.6 ~ 3.3kg, phosphorus fertilizer (p2o 5):0.6 ~ 1 kg, potassium fertilizer (K2O): 3.1~ 5.6kg, calcium fertilizer (Cao): 1 ~. The ratio of nitrogen, phosphorus, potassium, calcium and magnesium in the whole growth period is about1:0.27:1.42: 0.39: 0.16.

Eggplant needs different nutrients at different growth stages. The fertilizer requirement at seedling stage is very small, but it is very sensitive to the abundance and deficiency of nutrients. The supply of nutrients at seedling stage has great influence on plant growth and flower bud differentiation. With the growth of eggplant, the demand for fertilizer increases. Among them, the fertilizer requirement is the largest from the full fruit stage to the last fruit stage, and the absorption accounts for about 90% of the whole growth period.

From seedling stage to flowering and fruiting stage, the absorption of nutrients by eggplant plants is gradually increasing. After entering the picking stage, the nutrient absorption is the largest, the nitrogen and potassium absorption increase rapidly, and the calcium and magnesium absorption are also increasing.

Nitrogen fertilizer is indispensable in any period of eggplant growth. Lack of nitrogen will lead to weak plant growth and affect flowering and fruiting, and adequate supply can promote the good development of fruits.

The demand for phosphate fertilizer in eggplant is small, but it has an important influence on the flower bud differentiation of eggplant. Therefore, the supply of phosphate fertilizer should be sufficient in the early stage.

The demand for potassium in eggplant is the same as that for nitrogen in the middle growth period, and it increases significantly in the later growth period. The demand for nitrogen and potassium fertilizer is the greatest in the full fruit period.

Second, matters needing attention in the process of eggplant fertilization

Only when plants reach the physiological balance of various nutrients needed can they achieve high quality and high yield. Therefore, in the actual fertilization, it is necessary to rationally fertilize according to different cultivation methods and different growth periods.

Eggplant has a long fruiting period and needs a lot of fertilizer. Organic fertilizer should be based on base fertilizer, supplemented by chemical fertilizer. Phosphate fertilizer should be applied at one time in the base fertilizer, and nitrogen fertilizer and potassium fertilizer are divided into base fertilizer and topdressing. It should be noted that when applying base fertilizer, chemical fertilizer and organic fertilizer should be fully mixed before application.

1, seedbed fertilizer

Generally, 200 kg of organic fertilizer, 0.5 kg of calcium superphosphate 1 kg of potassium sulfate are applied per 10㎡ of seedbed fertilizer, and some peat and decomposed livestock manure can also be added to mix with seedbed soil. At seedling stage, if the young leaves of eggplant turn yellow, about 0.25% urea solution can be sprayed in time, which can restore the leaves of seedlings to dark green.

2. Base fertilizer

Eggplant has a long fruiting period. In order to ensure that eggplant has sufficient nutrition supply in the process of growth and development, it is necessary to apply sufficient base fertilizer to obtain high quality and high yield.

Open-field cultivation: it is recommended to apply base fertilizer for open-field cultivation, and it is recommended to apply about 5000 kg of decomposed farm manure or 450~550 kg of commercial European base fertilizer per mu; 10 ~15kg ammonium sulfate or 5kg urea; 30-40kg of calcium superphosphate or diammonium phosphate 10- 15kg, and 6- 10kg of potassium sulfate; before soil preparation, the fertilizer is scattered on the ground and then ploughed. Protected cultivation: It is suggested to apply about 8000 kg of decomposed farmyard manure, 25-35 kg of calcium superphosphate or 0/0-/0/5 kg of diammonium phosphate and 25-30 kg of potassium sulfate per mu for protected cultivation. 3. Surface treatment

Eggplant has a long fruiting period, so it is very important to master the key topdressing period for high yield.

(1), fruit fertilizer

The first ear fruit enters the swelling stage, which is the key period for the first topdressing of eggplant plants. Urea 10~ 17 kg and potassium sulfate 8~ 12 kg should be applied in combination with irrigation water.

(2) Fruit fertilizer

The second and third ears of eggplant enter the expansion period, which is the key period of secondary topdressing and the peak period of eggplant's demand for fertilizer and water. Generally, topdressing is needed for about 3 times in the full fruit stage, with urea 10~ 18 kg and potassium sulfate 8~ 14 kg each time. Topdressing can be applied with water, furrow or acupoint.

③ Late topdressing

In order to maintain plant growth and prevent premature aging, topdressing 1~2 times can be used in the late growth stage of eggplant to obtain higher yield.

4. Topdressing outside the roots

When the amount of potassium fertilizer is insufficient, potassium dihydrogen phosphate solution can be sprayed during the expansion period of eggplant, and the general concentration is 0.2%~0.5%. The eggplant cultivated in greenhouse should also enhance the photosynthesis of eggplant plants by applying carbon dioxide gas fertilizer. When applying carbon dioxide gas fertilizer, it should be applied in sunny morning, and the carbon dioxide concentration is1200 ~1500μ l/L. ..

When planting, fertilization should be applied scientifically according to the law of fertilizer demand in each growth and development period of eggplant, so that the cultivated eggplant can obtain high quality and high yield.