通过对澳洲坚果叶片的低温处理 ,测定其POD和Est同工酶 ,同时观察叶片冻害症状。结果表明 ;所试材料随处理温度降低 ,POD同工酶谱带减少 ,活性降低。Est同工酶也有类似情况 ,但不如POD同工酶有规律。澳洲坚果不同品种抗寒性差异较大 ,品种 34 4,2 46 ,实生苗在 - 5℃以上基本不受冻害。品种 788在 - 5℃ ,80 0 ,741在 0℃开始表现冻害。提出在极端低温 0℃以上地区为适宜种植区。 POD and Est isozymes were determined by low temperature treatment on Macadamia leaves, and the symptoms of frostbite were observed. The results showed that the temperature of the treated materials decreased, POD isoenzyme bands decreased, activity decreased. Est isozymes have similar conditions, but not as regular as POD isoenzymes. Different varieties of macadamia differ greatly in their cold resistance, with varieties 34 4 and 2 46, and the seedlings basically free from frost damage above -5 ℃. Variety 788 at-5 ℃, 80 0, 741 at 0 ℃ began to show frost damage. Proposed in the extreme low temperature above 0 ℃ area is suitable for planting areas.