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一、前言大白菜生长的适温范围在5～25℃之间,其中叶片生长最适温度是18～21℃,包心最适温度是15～10℃。在适温范围内,温度高则叶片生长快。若高过25℃,虽然叶片生氏也快,但由于呼吸作用增强,病虫害增多,养分累积少,因而品质祖糙。包心后,温度低于5℃,包心仍能进行。但若低于15℃以下的时间累积到2～3周,则花
I. Introduction The optimum temperature range for Chinese cabbage growth is between 5 and 25 ℃. The optimum temperature for leaf growth is 18 ~ 21 ℃, and the optimum temperature for packing is 15 ~ 10 ℃. In the temperature range, the high temperature leaves grow faster. If higher than 25 ℃, although the leaves of Health is also fast, but due to enhanced respiratory effects, increased pests and diseases, nutrient accumulation less, so the quality of ancestral roughness. After the heart, the temperature is below 5 ℃, heart can still be carried out. However, if less than 15 ℃ below the cumulative time of 2 to 3 weeks, then flowers