What is the effect of continuous rainy days on vegetable planting? How to deal with ensuring output and quality

Adverse effects of continuous rainy weather on vegetable growth

As long as the rainy weather lasts for more than 3 days or more, it will have different degrees of influence on the growth of vegetables.

1, plants are long and flowers are weak.

In rainy weather, it is especially common that vegetables are long and flowers are weak. This is mainly because in the case of high temperature and weak light, plants will grow in vain, which is caused by excessive nutrient consumption and organic nutrient accumulation. In the weak light environment, the organic nutrition synthesized by photosynthesis of vegetables and plants is inherently insufficient, and most of them are supplied for the vegetative growth of plants. At the same time, as long as the plants grow white, there will be weak flowers.

2. Insufficient supply of organic nutrition.

Organic nutrition is produced by photosynthesis of leaves, which is the premise for vegetables to grow plants and fruits. Without light, photosynthesis will be weakened and organic nutrients will be reduced. As long as the supply of organic nutrients is insufficient, many physiological diseases will occur. Such as cucumber with big head, pointed mouth and curved mouth; Non-expanded fruit and empty fruit of tomato; Eggplant and pepper do not flatulence after fruit setting; Beans and peas are both physiological diseases. The poor commodity of vegetables is directly related to the insufficient supply of organic nutrition.

3. Vegetables are deficient in elements.

When the supply of organic nutrition is insufficient on cloudy days, there are mainly four elements: calcium, magnesium, boron and iron. Umbilical rot, fruit cracking and bud blight of calcium-deficient tomatoes are directly related to calcium deficiency; Lack of calcium and boron in cucumber will lead to melon bending and scorching leaves at the growing point. The most typical symptom of iron deficiency is that after cloudy days, yellow heads appear at the whole growing point on sunny days. The premise of these element deficiencies is that they have poor resistance to stress. Under this premise, simply supplementing boron and calcium may not work. Therefore, it is extremely important to supplement medium and trace elements while improving its anti-stress ability.

4. The plants withered.

When plants wither in sunny days after cloudy days, the first thing to consider is whether there is a problem with the roots. There are three main reasons for plant withering:

Physiological root retting or root diseases: Due to insufficient synthesis of organic nutrients on cloudy days, most of them are supplied to plants for growth, and the organic nutrients distributed in the roots will decrease, leading to root necrosis.

Root diseases: root diseases can also lead to plant wilting, and fungal root diseases include root rot and Fusarium wilt; Bacterial root diseases include canker, pulp necrosis and bacterial wilt. According to the symptoms of wilting, including the manifestations of pulp and vascular bundles, we can judge what kind of disease it is, and then we can prevent it.

Physiological water loss: After several cloudy days and a sunny day, the transpiration required by leaves is particularly large, and the water supply absorbed by roots can not meet the needs of leaf transpiration. At this point, the whole plant will lose water and wither.

No matter what kind of situation leads to wilting, we should judge clearly and take corresponding countermeasures.

5, the disease occurs.

Continuous rainy days are likely to lead to diseases that require a high humidity environment. For example, tomato is cloudy after rain, fungal diseases such as gray leaf spot, bacterial diseases such as brown spot and macula, and moderate temperature and high humidity diseases such as late blight; Cucumber anthracnose, target spot disease and other diseases mostly occur under high temperature and high humidity conditions, such as downy mildew, leaf blight and so on. High temperature and high humidity cotton wilt and eggplant spot disease; Hot and humid pepper leaf blight, leaf spot and anthracnose; Colletotrichum gloeosporioides, brown spot disease and cotton blight of beans with high temperature and high humidity.

Countermeasures of vegetable planting after continuous rainy weather

I worked out the effect of rainy weather on vegetables. Let's talk about countermeasures first.

1, prosperity control should be strengthened and flower promotion should be followed up.

The premise of promoting flowers is to control prosperity. If all the plants are in vain, it is useless to promote flowers. The nutrients made by leaves are called organic nutrients, which are made during the day and run in the first half of the night. Where to run depends on the judgment of vegetables on the external environment. When vegetables feel that the outside temperature is relatively high, they will be transported to the plants by force. When the temperature is relatively low, such as winter, nutrients are supplied first. So, if it is not well controlled, how can we try to promote flowers?

Therefore, after continuous rainy days, it is suggested to spray flutriafol+medium and trace elements+biostimulant, and control the dosage of flutriafol according to the plant growth. If the plant still grows in vain after using flutriafol, Trim potassium dihydrogen phosphate or methylphenidate, a hormone drug for controlling flowering, can be added at the same time to promote flowering.

2. Improve the compression resistance and supplement organic nutrition after sunny days.

After cloudy days, it can improve stress resistance, supplement organic nutrition, and relieve plant wilting and physiological water loss. It should be done on the day before the arrival of sunny day or on sunny day, because the organic nutrition supply of vegetables on cloudy day is insufficient, and it is necessary to supplement organic nutrition to alleviate nutritional deficiency. It is suggested that plant-derived auxin+plant-derived amino acids should be sprayed on the leaves.

3. The conditioning of element deficiency

The premise of conditioning element deficiency is to improve resilience. After rainy days, if the new leaves at the growing point of plants turn yellow, it is suggested to spray them with plant-derived amino acids and chelated iron; If there is umbilical rot, scorched leaves, cracked fruit, etc. Spray plant-derived amino acids and trace elements.

4. Be sure to raise roots after cloudy days.

Many vegetable farmers have a misunderstanding that plants wither after cloudy days, and supplementing nitrogen, phosphorus and potassium can make plants grow rapidly. As everyone knows, the root system of plants is the most fragile at this time, and supplementing a large number of elemental fertilizers will only aggravate the damage to the root system. Therefore, as long as it is cloudy for more than 3 days, the first thing to do is to stop applying NPK fertilizer, whether it is compound fertilizer or Trim water-soluble fertilizer. At this time, the first priority is to raise roots first. There are two ways to raise roots after cloudy days:

Plant wilting: After cloudy days, plant wilting, except physiological water loss, is mainly caused by retting roots or root diseases. Therefore, as long as the plant wilts, it is recommended not to water it first, but to water the roots first. The purpose of root irrigation is to sterilize and raise roots at the same time. Use rooting fertilizer+trichloroisocyanuric acid to irrigate the roots, and use strong oxidant to reduce the pathogen base.

Plant does not wither: if the plant does not wither, it means that there is no root disease, just raise the roots.

5. Disease prevention

As soon as the cloudy day passes, the disease begins to happen. Therefore, after the cloudy day has passed, we must prevent the disease in time, and don't wait for the disease to become popular, then it will be too late. It is suggested to spray difenoconazole+dicyandiamide anthraquinone+kasugamycin+propamocarb hydrochloride, so that fungal diseases and bacterial diseases can be well controlled. If the disease has occurred, choose the corresponding therapeutic agent for treatment.

Persistent rainy weather will have many adverse effects on the growth of vegetables. By taking targeted measures, these potential hazards will be reduced to a minimum, thus ensuring the yield and quality of vegetables.