Why can't leafy crops be planted in hot weather?

If the temperature is abnormally high. There is no doubt that it will hit agriculture. In the final analysis, abnormal high temperature is the water source problem of agriculture. High temperature makes ground water evaporate and soil water decrease, which seriously affects crop growth. If farmers take measures to irrigate crops, they will increase their production input and their future profits will be affected. Because of the water problem, crop production is blocked, which directly affects crop prices.

The harm of high temperature crops to rice is usually more obvious. The harm of rice is characterized by premature aging and yellowing of the last three functional leaves, shortened filling period, reduced 1000-grain weight and increased incidence of Fusarium wilt. The hazard index is that the maximum temperature is ≥35℃ for three consecutive days or more, which leads to high temperature maturity of rice during flowering and filling. The filling period of early rice, middle rice and hybrid rice in the south of the Yangtze River is midsummer, which is often harmful to them. Guangdong early rice will also mature at high temperature in continuous high temperature drying years.

High temperature will also lead to flowering of vegetables, reduce the fruit setting rate, and adversely affect the growth and development of cucumber, eggplant and kidney bean. Potatoes will degenerate and become smaller after being damaged. Thermal damage of fruit trees and trees includes sunburn of fruit trees and forest burns. Heat damage is caused by high temperature, because high temperature will inactivate chlorophyll in plants, hinder normal photosynthesis, reduce photosynthetic rate, greatly increase consumption, make protein in cells agglutinate and denature, lose semi-permeability of cell membrane, and damage plant organs and tissues.

High temperature will also reduce the transportation ability of photosynthetic products to panicles and the activity of enzymes, resulting in shortened filling period, incomplete grains and decreased yield.