【摘要】 [目的]研究低温胁迫下外源水杨酸和硒复配剂处理对铁皮石斛抗寒性的影响。[方法]以生长一年的铁皮石斛组培苗为供试材料,2℃低温胁迫7 d后,用不同浓度的外源水杨酸和硒复配剂进行叶面喷施,其中外源水杨酸和硒均设置了4个浓度梯度,分别为0、15、30、60 mg/L和0、5.0、7.5、10.0 mg/L,采用不完全随机设计将二者进行复配,共12种复配剂。[结果]低温胁迫下外源水杨酸和硒应配合使用,叶绿素含量和PRO含量的增加,SOD、POD和CAT活性增强,MDA含量下降;喷施浓度为15/10.0、30/5.0和30/7.5 mg/L的水杨酸和硒复配剂时,其叶绿素含量、PRO含量、抗氧化酶活性均显著增加,MDA含量显著下降,显著提高铁皮石斛抗寒性,缓解铁皮石斛的低温伤害。[结论]低温胁迫下配合使用外源水杨酸和硒,可在一定程度上减缓铁皮石斛的低温伤害。更多还原

【Abstract】 [Objective]To explore effects of salicylic acid and selenium on cold resistance of Dendrobium candidumin under low temperature stress. [Method]Based on Dendrobium candidum seedlings as experimental material, the stress of low temperature 2 ℃ after 7 d, with different concentrations of exogenous salicylic acid and selenium compound spraying on the leaf. The exogenous salicylic acid and selenium were all set up four concentration, respectively 0,15,30,60 mg/L,and 0,5,7.5,10.0 mg/L,not completely random design will both for distribution, a total of 12 kinds of complex dispensing. [Result]The results showed that exogenous salicylic acid and selenium should be used together in low temperature stress, which was reflected in the increase of chlorophyll content and PRO content, the increase of POD,SOD and CAT activity, and the decrease of MDA content.Salicylic acid and selenium treatment(15/10、30/5 and 30/7.5 mg/L) could increase the cold resistance of Dendrobium candidum seedlings, which was achieved by means of enhancing the anti-oxidative enzyme activities, chlorophyll content and PRO content, and decreasing the MDA content to reduce injury of in low temperature stress. [Conclusion]Exogenous salicylic acid and selenium should be used together under low temperature stress, which can slow down the low temperature injury of Dendrobium candidum to a certain extent.更多还原