Latest Technical Guide to the Prevention and Control of Cold Injury and Freezing Injury in Cucumbers

In greenhouse cucumber cultivation during autumn, winter and early spring, because the air temperature is cold, cold injury and freezing injury are extremely prone to occur. In early spring the leaves turn yellow and growth is damaged, and in severe cases the plants wilt and die. So how should cold injury and freezing injury be prevented and controlled? Follow the editor to learn about it.

I. Causes of Low Temperature and Freezing Injury

The longer the low temperature and the low temperature last, the faster the temperature drops, and the more severe the cold injury and freezing injury of cucumbers become; conversely, the milder they are. If the air temperature drops slowly, then the symptoms of freezing injury and cold injury are milder. If low temperature is followed by clear weather, then cold injury and freezing injury are aggravated. If low temperature is followed by cloudy weather and the temperature gradually rises, cucumbers will gradually recover their physiological vitality, and cold injury and freezing injury will be somewhat milder.

II. Preventive Measures

When transplanting, grafted seedlings can be used. According to experimental surveys, in the same greenhouse the wilting rate of all ungrafted seedling plants reached more than 10%, while that of grafted seedlings was only about 10%. Before the Beginning of Spring, greenhouse cucumbers are extremely susceptible to cold wave invasion, so nitrogen fertilizer should be applied as little as possible, and watering should be controlled at the same time, so as to prevent the seedlings from growing excessively and reduce the cold resistance of the seedlings, which would make freezing injury and cold injury to the seedlings more severe. Before the cold wave arrives, some straw can be lit at intervals to produce smoke, which can also alleviate cold injury and freezing injury; however, note that the amount of smoke should not be too large, so as to prevent the seedlings from being killed by the smoke, and also be careful not to cause open flames. After cucumbers have suffered from sustained low temperature damage, when clear weather comes again, do not immediately remove the straw curtains; instead, remove the straw curtains gradually, to avoid a sharp rise in temperature that burns the seedlings.

III. Remedial Measures

Fertilizer and water management should be strengthened to prevent premature leaf senescence. After the stem tip develops bacterial wilt, fertilizer and water management should be strengthened to prolong the photosynthetic function period of the original leaves on the main vine. On each clear day, maintain about 28 degrees during the day and no lower than 12 degrees at night; irrigate once a week under the film, and apply nitrogen fertilizer once every two weeks together with irrigation. After the cucumber plants resume normal growth, their nutrient level is relatively sufficient, and lateral branches and back cucumbers will both be produced in large numbers; however, the cucumbers on the lateral branches are of poorer commercial quality, and the main vine already has a certain length, so all lateral branches need to be pinched off at the tip, forming a relatively long peak production period.

The above is an introduction to the prevention and control techniques for cold injury and freezing injury in cucumbers. We hope it can help you. To learn more related knowledge, please keep following us.