高温胁迫下外源茉莉酸甲酯、钙和水杨酸对蝴蝶兰幼苗耐热性的影响

为了探求外源茉莉酸甲酯、钙和水杨酸对蝴蝶兰耐热性的影响，分别采用最适浓度的3种药液和蒸馏水（对照）喷施蝴蝶兰幼苗叶片，并置于40℃高温胁迫4天，测定了有关生理指标的变化。结果表明：高温胁迫下，与对照处理相比，茉莉酸甲酯、钙处理明显提高了SOD、POD、CAT活性，而水杨酸处理在明显提高了SOD、POD活性的同时，却明显降低了CAT活性；3种处理明显提高了可溶性蛋白质和脯氨酸含量，显著降低了相对电导率和MDA含量。由此认为，茉莉酸甲酯、钙、水杨酸处理能提高蝴蝶兰幼苗的耐热性。根据形态和生理指标的差异性，可得出诱导耐热性强弱的顺序为：茉莉酸甲酯>钙>水杨酸。

Effect of Exogenous Methyl Jasmonate, Calcium and Salicylic Acid on the Heat Tolerance in Phalaenopsis Seedlings under High Temperature Stress

In order to reveal the effect of exogenous methyl jasmonate（MeJA） and calcium and salicylic acid（SA） on the heat tolerance in Phalaenopsis seedlings,these seedlings sprayed with 3 chemicals at the optimum concentration or distilled water（control） respectively were exposed to high temperature stress at 40℃ for 4 days,the variations of some physiological indexes in the leaves were measured.The results showed that,compared with the control treatment,the MeJA and calcium treatments resulted in higher activities of SOD and POD and CAT.The SA treatment made the activity of CAT decrease significantly,while it could increase the activities of SOD and POD.The 3 treatments could improve obviously the contents of prolin and soluble protein,and decrease significantly the relative electrical conductivity and MDA content under high temperature stress.According to these results,it indicated that the MeJA and calcium and SA treatments could enhance effectively the heat tolerance in Phalaenopsis seedlings.On the basis of physiological and morphological indexes difference,the inducting intensity of the heat tolerance was in the following order：MeJAcalciumSA.