Effects of Shed Temperature on Cucumber Physiology

Effects of Shed Temperature on Cucumber Physiology

Water, temperature, gas and heat are the basic conditions for cucumber growth and development. The main problem solved by the protected cultivation is the temperature problem, that is, through the greenhouse and the greenhouse, creating a suitable temperature environment for the growth of cucumber. Any kind of crop growth has its own suitable conditions, and the control of environmental factors is a very important aspect. Greenhouse planting is produced under this demand. In the face of variable environmental factors, we can use the temperature illuminance recorder to measure the temperature and illumination of the environment at any time and make appropriate adjustments. In addition, self-reporting rain gauges and wind direction wind speed monitors are also some of the instruments often used in weather monitoring. Meteorological testing plays an unassailable role in agriculture and its importance has been recognized by more and more people. This is also the reason for the rapid development of meteorological testing in recent years. However, the difference in temperature between the sheds is large, and the temperature required for cucumbers is basically regular. Under conditions where the temperature is not appropriate, the cucumbers cannot grow normally and there are some physiological temperature disorders, ie physiological diseases.

1. Apprentice. High temperature and high humidity are the main factors leading to leggy. Seedlings easily form tall seedlings, resulting in long internodes, easy lodging, poor flower bud differentiation, the result is small and thin. During the growing period of the vegetables, the purpose of cooling can be achieved through the use of ventilation, shade nets, cooling agents, water spray, grass cover curtains, splashing mud and other measures, and the ventilation openings on the northern wall can have better cooling effect. The suitable temperature for cucumber seedlings is 25~28°C during the day and 13~15°C during the night. The melon period is 28~32°C during the day and 13~17°C at night. In this range, the temperature is preferably lower. 2. Growth inhibition. During the growth period of cucumber, photosynthesis will be difficult to perform if it is above 35°C for a long time, ie, the respiration is greater than photosynthesis, which means that the nutrients produced are not as much as consumed. When the night temperature is too high, respiratory consumption is even more severe. Cucumber grows weak, premature aging, and low yield. 3. Malformed melons. Due to the increased photorespiration caused by high temperatures, the production and transportation of photosynthetic products is hindered, and the supply of organic nutrients is reduced, and it is difficult for the young cucums to sit. Big melons grow poorly, and they are easy to produce thin-shouldered gourds and pointed gourds. Variety of miscellaneous melons increased, resulting in a significant reduction in quality and commerciality. 4. The lack of disease. The high temperature increases the amount of evaporation of the soil, and the transpiration of the leaves increases. Due to the soil drought, the water supply is insufficient, and various elements such as phosphorus and calcium have poor mobility, and physiological phosphorus deficiency and calcium deficiency problems are prone to occur. In addition, iron deficiency, zinc deficiency, and yellowing can also be caused in the top leaves. 5. Leaves burned. Under the conditions of high temperature, low humidity, strong light, the leaves are prone to leaf cell necrosis and “dry edge” phenomenon, especially when the plants are subjected to cold damage and freezing injury. Once high temperatures and strong light are encountered, the leaves will inevitably lose water quickly. Large area of ​​scaly white dry spots. Note: This symptom cannot be diagnosed as bacterial leaf blight. 6. Drizzle. Spraying at high temperatures around noon is very prone to phytotoxicity. Although the efficacy is rapid when the temperature is high, it is also prone to phytotoxicity. Such as DDV, insecticidal composition of insecticidal components, pyrimethanil, sclerotia net, B-phosphorus aluminum as a bactericide.