一、传统的需冷量概念果树需冷量,一般是指果树休眠期对低温的得要量,常以一定条件下低温积累的小时数表示。树种不同、品种不同,其需冷量也不同。传统意义上果树休眠需冷量的概念,常有以下三种不同的说法:一是≤7.2℃低温积累的小时数;二是0-7.2℃低温积累的小时数;三是2.4-7.2℃低温积累的小时数。就某一特定的果树品种而言,应用不同需冷量概念,在不同地区、不同年份,所测算的需冷量也不同。一般越严寒地区,气温变化越大的年份,误差越大。这样,同一果树品种,可能出现多个 First, the concept of the traditional need of cold fruit trees to be cold, usually refers to the amount of fruit trees dormancy on the low temperature, often under certain conditions, the accumulation of low temperature hours said. Different tree species, different varieties, their cold capacity is also different. Traditionally, the concept of fruit dormancy cold demand, often the following three different views: First, ≤7.2 ℃ low temperature accumulated hours; second is 0-7.2 ℃ low temperature accumulated hours; third is 2.4-7.2 ℃ low temperature Accumulated hours. For a particular fruit tree species, the application of different concepts of demand for cold, in different regions, different years, the measured cooling capacity is also different. Generally the more cold areas, the greater the temperature changes in the year, the greater the error. In this way, the same fruit variety may appear more than one