How to deal with frozen vegetables, remedy methods after frozen vegetables, how to prevent frozen vegetables.

With the increasingly low temperature, greenhouse planting is easy to appear low temperature obstacles, vegetables appear freezing damage and even dead trees. How to avoid vegetable frostbite is directly related to the quality of vegetables and the price after listing.

There is a very big difference in biology between freezing and cold.

Low temperature chilling injury

During the growth and development of vegetables, the temperature drops to above 0℃ in a certain period, but it is lower than the minimum temperature suitable for growth, resulting in leaf yellowing, withering, falling flowers and fruit, fruit deformity and other harmful conditions.

Frozen vegetable damage

During the growth and development of vegetables, when the temperature is below 0℃ for a long time, the water in the plant is frozen, the vegetable plant tissues are injured, and the whole plant is seriously frozen to death.

Occurrence of low temperature chilling injury and freezing injury: in winter and early spring, it is easy to drop sharply to below the temperature suitable for vegetable growth. Whether vegetables grown in greenhouses or vegetables grown in the open land in south China, they are likely to suffer from chilling injury, and sheds with poor insulation effect often occur.

Sometimes the temperature drops suddenly, but also accompanied by sudden freezing and snow damage, such as extreme low temperature and heavy snow collapse of the shed, causing serious freezing of vegetables in the shed.

The symptoms of hypothermia are mainly divided into two types:

Delayed chilling injury

The photosynthesis and nutrient absorption capacity of vegetables decreased, the growth almost stopped, the new leaves did not grow, the slow seedling appeared in colonization, and the development stopped at the flowering and fruiting stage. From the observation of vegetable leaves, some leaves deepened green, some turned light yellow or yellow, some turned red or purple, and even the whole plant gradually withered.

Obstructive cold injury

From the leaf observation, there will be dead spots, disease spots gradually bleaching; In the flowering and fruiting stage, the flower apparatus is damaged, which affects flowering, flower deformity or falling flower, and young fruit deformity or falling fruit.

Symptoms of frost damage: mainly reflected in seeds, leaves, stems, fruits, roots and other parts of crops.

Freezing damage of seeds and leaves

Frost - damaged seeds are generally more difficult to sprout.

Vegetable leaves will become thin and rotten when frozen, as if they had been scalded. In cucumber, pepper, tomato and other plants, the leaf margin is dark green, the back of the leaf appears "water stains" water spots, then appear water loss, and finally withered.

How to prevent cold injury and freezing injury?

1. Select some varieties with strong freezing damage resistance. If you do not know much about the varieties with freezing resistance, it is recommended to try planting first.

2. Vegetables can not be planted in low-lying, windy and poor soil plots. Vegetables in protected areas should be built with good insulation performance.

3. Pay attention to the application of rancid farm fertilizer and control the amount of nitrogen fertilizer appropriately to improve the ability of vegetables to resist freezing damage.

4, seedlings before transplanting, in advance of a certain time of low temperature refining, improve their ability to resist freezing damage.

5. Pay attention to listening to the weather forecast. Before the cooling weather, prepare to use sunshade net, straw curtain, plastic film, thermal insulation quilt and other thermal insulation materials. 1-2 days before the onset of freezing damage can be poured once antifreeze water.

6. For rain and snow weather, the snow on the greenhouse should be cleaned in time to prevent the snow on the shed from collapsing. Clean and drain drains in time.

How to remedy cold damage and freezing damage?

First, timely supplement

Cold damaged vegetable plants are relatively weak, need timely fertilization to supplement nutrition, ransomed fertilizer is the best, can also add thin fertilizer, but pay attention to the concentration of fertilizer is not too high, should be with the vegetable growth recovery, gradually increase the concentration or dosage.

Two, clean up dead leaves

If the ground leaves wither and die at seedling stage and can produce new leaves, clean up the dead leaves in time.