After the rain, as the temperature continues to rise, sunshine increases gradually, especially after the start of summer, vegetable cultivation will usher in a long period of high temperature and strong light conditions, which is a big test for vegetables. If it is not properly managed, it will cause heat damage to the vegetables, usually manifested as plant growth, abnormal flower bud differentiation, poor pollination and fertilization, serious flowering and falling fruit, and abnormal fruit growth, affecting the yield and quality of vegetables. How to prevent vegetables from being roasted?

First, the high temperature and light damage to the growth of vegetables

1, poor flower bud differentiation, less female flowers

The flower bud differentiation of vegetables is closely related to factors such as temperature and light. Even cucumbers, gourds and other high-temperature crops are prone to high flowering node positions, reduced female flower numbers, no female flowers, or female flower abortions due to high temperature season. This is because Flower bud differentiation is not only related to genetic factors, but also directly affected by the temperature and length of sunshine. Long-day high-temperature sunshine is usually conducive to the differentiation of male flowers, female flowers are relatively reduced, and low-temperature and short-day sunshine are beneficial to the differentiation of female flowers.

2, plant length, vegetative growth and reproductive growth are not balanced

High temperature, especially high night temperature, strong plant respiration, excessive organic nutrient consumption, resulting in suppression of leggy plants, reproductive growth, and problems such as less flowers, small flowers, and difficulties in fruit setting, or even fruiting, are likely to occur. Falling fruit and malformed fruit and other issues.

3, high temperature and light cause a variety of physiological problems

Absorption of moisture and nutrients Temperature is above 30°C. If it is not watered in time, it will cause soil drought. When the vegetable roots absorb water from the soil can not meet the needs of plant evaporation, plant leaves tend to curl, fall off, or even dry; High temperature and drought, easily lead to elemental malabsorption, such as cabbage easy to get dry heart, tomatoes are easy to get umbilical rot.

Sunburn, bad color, high temperature is usually accompanied by strong light, greenhouse vegetables often appear sunburn phenomenon, in which pepper vegetables are most prone to occur, the fruit is burned by light, often in the sunny side of the fruit appears rotten, just At the beginning, the diseased part of the disease appears dark brown, and then the diseased part gradually turns brown. Finally, the diseased part of the disease will turn white, then expand slightly, white or light brown, the cortex becomes thin, the tissue is necrotic, and then it is susceptible to fungal infection, when the humidity is high. It also causes bacterial infestation and causes the entire fruit to rot and loses its commercial value. In tomato coloring, when the temperature is lower than 10°C or higher than 30°C, the synthesis of lycopene is inhibited, so the tomato is exposed to high temperature and strong light. The synthesis of red pigment is inhibited and affects tomato coloration.

Fast weather changes, vegetables are vulnerable to high temperatures in summer are often accompanied by rain, after the rain, the leaves are delicate, if improper management after a sudden fine, easy to cause damage to the leaves, and the hot sun and rainstorms are more likely to occur splitting.

4, plant resistance decreased, multiple pests and diseases

When the air temperature or ground temperature is higher than the normal temperature range of vegetable plants, disease resistance of some disease-resistant varieties will be reduced, they will become susceptible varieties, aggravate the occurrence of diseases; under high temperature and drought conditions, suitable for Pests, thrips, whiteflies and other pests develop and multiply, and pests act as vectors, causing high rates of viral disease.

Second, the main measures to deal with high temperature and strong light weather

1, choose heat-resistant, disease-resistant varieties

In the hot season, select vegetable varieties with strong heat resistance and strong resistance.

2, pay attention to shading and cooling

Cover shady and high-temperature weather to set up shade net in the roof to reduce the light intensity in the roof. However, it should be noted that the shade nets must not be covered all day to avoid insufficient lighting in the sheds. Generally, shades should be set before 10 am and before 3 pm. In the sunny weather after the rain, the plants are easily damaged, and the shade should be used in time to prevent the occurrence of sunburn and leaf burning. In open field cultivation, a simple shade shed is set up on the vegetable plots, covered with branches or crop straws, and covered with sparse flower sheds to achieve the purpose of cooling.

Changing the light transmittance of the shed film The mud is the most economical one, but it is not rain-resistant and it must be splashed again after the rain. The dosage can be controlled according to the intensity of light and the transparency of the film, and ink can be used to achieve the purpose of cooling the shade.

The use of cooling agents can be used to spray cooling agents on the shed film, which can effectively avoid the problem of rain erosion, obvious cooling effect, good light transmission, and does not affect photosynthesis.

3, high pole crop cover

Make full use of the shade of high-stalk crops to improve the mix between Xiyang and Xiyin crops. Such as cowpea and pepper intercropping, bitter gourd and pepper intercropping, maize and pepper intercropping, in the mulberry, tea, orchard to interplanting ginger in the shade.

4, ensure the timely supply of moisture and nutrients

Watering is one of the most effective measures for alleviating hot weather. The number of waterings and the amount of watering each time can be appropriately increased. When conditions permit, sprinkler irrigation or spraying of water can be used to prevent dehydration of the leaves. The time should be selected in the early morning or late afternoon. Do not water at high temperatures at noon. Use well water or low-temperature river water, and pour it thoroughly to keep the soil moist. To timely apply composite chitin organic water soluble fertilizer to cultivate strong root system, enhance the ability of plants to resist high temperature weather, and timely spraying of foliar fertilizer containing trace elements to supplement the nutrient consumption of plants, regulate plant growth.

5, reasonable sparse leaves

Solanaceous vegetables in summer should be left as leaves, so that the fruit can be hidden under the leaves as much as possible, avoiding direct sunlight. Therefore, when Solanum vegetables are used in high temperature weather, they must be avoided at high temperatures at noon. It is better to choose after 3 pm. In addition, when the summer vegetables are planted, the spacing of the plants should be dense, so that the stems and leaves can be sheltered from one another and the fruits can be prevented from direct sunlight.

6, enhance ventilation

When the temperature is high during the day, open the air outlets at the upper part and the front face of the greenhouse to strengthen the air release. As time progresses, the temperature continues to rise and the tuyere can be opened at night to cool down. In addition, a 60-mesh insect net should be placed at the same time as the air outlet, which can effectively prevent the invasion of pests and reduce the occurrence of pests and diseases.

7, timely and appropriate fertilization, medication

Vegetables are exposed to high temperature and strong light and their metabolism will be strengthened. If improper use of anthers, pharmaceutics and fertilizers can cause problems such as phytotoxicity, hormonal intoxication, and fertilizer damage, they must be used with caution and fertilization at high temperatures. In particular, the use of plant growth regulators such as anthers should be controlled to use concentrations.

8, pay attention to prevent diseases and pests in advance

The high temperature and drought conditions in summer provide favorable conditions for the propagation of pathogens and pests. Once an outbreak is more difficult to control. Therefore, we must strengthen monitoring, prevention in advance to achieve better control results.

Amorphous Hydrogel

Amorphous Hydrogel,Amorphous Hydrogel Dressing,Amorphous Gel Dressing,Hydrogel Amorphous Gel

Roosin Medical Co.,Ltd , https://www.roosinmedical.com