Abstract: Based on many years continual determination of temperature for the populations of wheat varieties by means of infrared technique, the temperature type phenomenon of wheat is discovered. Each temperature type of wheat has its distinct characteristics in its external and internal characters. Cold typal wheat is superior than warm typal one in many important characters:the functional period of its functional leaves is 10.8% longer, its root number per plant is 20 more, and the chlorophyll content, transpiration rate and net photosynthetic rate of its flag leaves are respectively 0.1389 g·100g^-1 ·FW,0.0035 mol·m -2 ·s^-1 and 4.71 μmol·m -2 ·s^-1 higher.It is considered that the temperature type wheat is closedly related with a series of important characters of wheat.

Key words: Temperature type, Cold typal wheat, Character, characteristic scale., spatial scale, landscape pattern, scale effect