Watermelon seedlings in the greenhouse will wither in rainy days. How to remedy in time?

Rainy days are really annoying, and the subject's mind at the moment is estimated to be rainy days. However, the subject should not worry. There are three reasons why watermelon seedlings suffer from rainy weather. One is the lack of light, the other is the drop in temperature, and the third is the high humidity. In this regard, the present situation of Yimeng farmers provides suggestions for the subject.

First of all, let's analyze the reasons:

1. Insufficient light. Adequate light is the guarantee of photosynthesis of melon seedlings. Insufficient light in rainy weather greatly reduced the photosynthetic efficiency of melon seedlings and reduced the organic matter needed for their own production. Moreover, the breathing of melon seedlings needs to consume nutrients, which can be said to make ends meet.

2. The temperature drops. The effect of cooling reduced the activity of enzymes in melon seedlings, and then slowed down the photosynthesis of melon seedlings, and the nutrients produced were far from meeting the needs of life activities of melon seedlings. At the same time, too low temperature will also cause chilling injury to melon seedlings.

3. Humidity increases. Rainy weather makes the air humidity and seedbed humidity in the shed increase relatively. Too much water in the seedbed soil will reduce the oxygen content in the soil, and the root system of melon seedlings will be prone to lack of oxygen, and at the same time, harmful gases emitted by melon seedlings will be easy to accumulate. In this case, it is easy to cause root retting. Once the root system of melon seedlings is injured, the absorption of water and inorganic salts can not be guaranteed normally, and the growth of melon seedlings will be affected.

Through the above analysis, when watermelon seedlings encounter rainy weather, they should start with enhancing illumination, controlling temperature and humidity and proper ventilation.

Second, do the following prevention and control measures

1. artificially strengthen the light intensity. ① Install fluorescent lamps, such as incandescent lamps. Make up the light all day, and control the light intensity, with 2000 lux as appropriate, to ensure sufficient light in the greenhouse. (2) Hanging reflective curtain and laying silver-gray film. On the back wall or column of greenhouse, 6 square meters of aluminum-plated reflective curtain is hung every 5 meters, and silver-gray film is laid on the ground to increase the light intensity between plants.

2. Increase the temperature in the shed. (1) Cover the grass cover with a plastic film. Prevent the loss of heat caused by rain wetting the grassland. (2) Cover the melon seedlings with plastic film. This can not only increase the temperature, but also reduce the humidity of the seedbed. (3) When necessary, burn the stove in the shed.

3. Not suitable for watering and proper fertilization. It is forbidden to water melon seedlings in rainy days. Alleviate the root retting of melon seedlings and prevent the ground temperature of seedbed from dropping. ② Less application of biological bacterial fertilizer. The roots of stored melon seedlings grow and develop to ensure the normal absorption of water and inorganic salts by the roots.

4. Maintain proper vigilance. Open the vent at noon every day, the opening should not be too large, preferably not more than 10cm, and the ventilation time should be controlled at 10 minute, which can effectively exhaust the harmful gases accumulated in the greenhouse and effectively reduce the air humidity in the greenhouse.

The above is my experience in preventing watermelon seedlings from slanting in rainy days.