Using the aseptic seedling of Kalmia latifolia ' Peppermint' and ' Bullseye' as experimental materials, the heat tolerance of K.latifolia and some relative physiological indices were determined and analyzed under the stress conditions of 25℃,30℃, 35℃, 40℃, 45℃ and 50℃.The relative conductivity, Chlorophyll, soluble protein content and free proline content of each plant were measured.Caculated the lethal temperature by Logistic equation, and evaluated the cold-hardiness by the subordinate function.The result showed that the LT50 for ' ...