金钗石斛对温度的生理反应

 目的研究金钗石斛对温度的生理反应，确定其生长的适宜温度范围。方法利用人工气候箱，于同一光强下设置不同的温度梯度对金钗石斛进行处理；采用754GW紫外．可见分光光度计测定石斛叶中MDA，可溶性蛋白质、可溶性总糖及叶绿素含量；POD，CAT活性及其同工酶电泳。结果石斛的生理活性随温度由低到高，表现出弱，强，弱的变化规律；25℃处理石斛的可溶性蛋白质含量、总糖含量、叶绿素含量及CAT活性均显著高于其它处理，MDA含量及POD活性，则显著低于其它处理；CAT活性与MDA含量呈显著负相关，而POD活性与之呈显著正相关；CAT，POD同工酶分析表明，温度引起石斛同工酶谱带数目的增减或强弱的改变，其变化与相应酶活性基本一致。结论25℃的平均温度(23～28℃)有利于促进金钗石斛的生长与代谢，是其生长的适宜温度。

Physiological reactions ofDendrobium nobile to temperature

OBJECTIVE To identify the suitable range of temperature of Jinchai Shihu(Dmdrobium nobrle)growth and its physiological reactions to temperature. METHODS The plant was treated with the different temperatures,(15,20,25,30 and 35℃)respectivelyin 20KLX light intensity in the artificial climate chests. The activity of POD,CAT,the contents of soluble protein,total sugar,MDA and chlorophyll in leaf were detennined by 754 GW specord UV vis. The zymoyams of CAT and POD isoenzymes were studied by PAGE.RII:SULTS The physiologi-cal activity of Jinchai Shihu showed the“weakness-strength-weakness”regularity from lower temperature to higher temperature.The contents of soluble protein,total sugar and chlorophyll,CAT activity of the treatment at 25℃were highest and the content of MDA and activity of POD were lowest in all treatments The content of MDA was negatvely related to the CAT activity and postively related to the POD activity.The analysis of lsoenzymes indicated that the changes of zymogram were in agreement with the activities of corresponding enzymes. CONCLUSION The suit-able growth temperature of Jinchai Shihu is 25℃