What about the lack of chlorine in crops? What are the symptoms? How to use chlorinated fertilizer?

Chlorine is one of the essential elements for rich growth and development. Many plants will grow poorly if they lack chlorine. What about chlorine deficiency in crops? What are the symptoms? How to use chlorine fertilizer? Let's take a look.

1. The effect of chlorine on crops

1. Participation in photosynthesis In photosynthesis, chlorine participates in the photolysis reaction of water as a cofactor of manganese. Water photolysis is the first photochemical reaction of photosynthesis.

2. Chlorine regulates the opening and closing of stomata in crop leaves, thus enhancing the drought resistance of plants. In addition, chlorine has the ability to bind water, which helps crops extract more water from the soil.

3. Chlorine-containing chemical fertilizer can inhibit the occurrence of many diseases. At least 10 crops are reported to have significantly reduced disease levels through increased application of chlorine-containing fertilizers. For example, stripe rust of spring wheat, root rot of barley, stem blight of corn, etc.

Chlorine activity is very strong, very easy to enter the plant body, and can promote the absorption of ammonium ions and potassium ions by plants.

II. Symptoms of Chlorine Deficiency in Crops

The general symptoms of chlorine deficiency are plant atrophy, leaf chlorosis and leaf size reduction. Chlorine deficiency symptoms of different crops are not exactly the same, for example, spring wheat chlorine deficiency performance for plant leaves yellow, and there are many spots; lettuce, cabbage and alfalfa chlorine deficiency performance for leaves wilting, but the root is thick and short rod, young leaf edge rolled up cup shape; cotton chlorine deficiency, leaves wilting, dark green, serious, leaf edge dry, curly.

III. What about chlorine deficiency in crops?

Chlorine deficiency is rare in the field because of the wide sources of chlorine. Chlorine carried in the atmosphere and rainwater alone far exceeds the annual requirements of crops. Once chlorine deficiency occurs, chlorine-containing fertilizers, such as ammonium chloride and potassium chloride, can eliminate symptoms.

IV. How to use chlorine-containing fertilizer?

1. Avoid use on sensitive crops and sensitive periods of crops: Chlorine sensitivity and tolerance vary widely among crops and varieties. Chlorine-sensitive crops are called chlorine-resistant crops, such as tobacco, tea, citrus, grape, watermelon, potato, Chinese milk vetch, etc., and generally do not apply or strictly control the application amount of chlorine-containing chemical fertilizers.

2. Pay attention to the application method of chlorine-containing chemical fertilizer: when using chlorine-containing chemical fertilizer as base fertilizer, it should be applied deeply and covered with soil in advance, generally one week before sowing or transplanting seedlings, and applied to the lower side of seeds or seedlings, 5~7 cm away from the topsoil. For topdressing: adopt hole or strip application, and 5~10 cm away from crop plants, do not spread.

3. Chlorine fertilizer should be applied in seasons and areas with more rainfall as far as possible: chlorine fertilizer should be applied in rainy seasons or areas with more rainfall. Chlorine ions can be leached with water and are not easy to accumulate in soil, thus avoiding side effects on crops. It is better not to use or use less chlorine-containing chemical fertilizer in dry land without irrigation conditions, saline land with poor drainage, high temperature and dry season and water shortage and little rain area.

5. Which plants are suitable for chlorine-containing fertilizers?

Different crops have different sensitivity to chlorine. Some plants are very sensitive to chloride ions, and when the absorption reaches a certain level, it will obviously affect the yield and quality. These plants are usually called chlorine-resistant plants.

When chloride ion is more, it is not conducive to the conversion of sugar into starch, and the starch content of root and tuber crops will be reduced; chloride ion can promote the hydrolysis of carbohydrates, watermelon, sugar beet and grape will reduce the sugar content; chloride ion is more, which will affect the combustion of tobacco, and cigarettes are easy to extinguish; chloride ion is more, often causing harm to the seedlings of sensitive crops.

Tobacco, potato, sweet potato, sugarcane, watermelon, grape, citrus, beet, apple, tea, cabbage, pepper, lettuce, amaranth and so on are all chlorine-free crops. Chlorine can adversely affect solanaceous crops. Chlorine resistance of soybean and kidney bean was weak.

Chlorine-sensitive crops, such as tobacco, sweet potato, cabbage, pepper, lettuce, amaranth, apple, grape, tea, watermelon, etc., often affect the quality of products when chlorine-containing fertilizers such as ammonium chloride and potassium chloride are applied. For example, too much chlorine will reduce the burning of tobacco, bad smell, starch content of potato crops decreased, poor quality; reduce the sugar of fruit, and high acidity, so that the fruit flavor is poor. Therefore, sulfur-containing fertilizers should be selected as far as possible when selecting fertilizers for chlorine-sensitive crops.

On the contrary, crops that are not sensitive to chlorine, such as rice, sorghum, millet, cotton, corn, wheat, peanuts, soybeans, tomatoes, etc., can not only save fertilizer costs when applying chlorine-containing fertilizers, but also have better effects on certain crops. For example, fiber crops such as cotton and hemp, potassium chloride application is beneficial to increase their fiber length and toughness; chlorine fertilizer application in paddy fields is often better than sulfur fertilizer, because it can reduce hydrogen sulfide damage to rice roots.