吴进东

摘 要：为了解不同浓度6-BA对霍山石斛（Dendrobidium huoshanness）耐热性的影响，以二年生霍山石斛的当年生茎叶为试验材料对其进行试验研究。结果表明，昼/夜温度分别为（35±1）℃/（25±1）℃的高温胁迫下，随时间推移，霍山石斛叶片叶绿素含量不断降低；SOD、POD与CAT的活性均先提高后降低，峰值在高温胁迫后10d；MDA含量不断提高；茎中多糖含量下降。6-BA显著缓解了高温胁迫对霍山石斛伤害，显著提高其叶片叶绿素含量；提高SOD、POD与CAT的活性，降低MDA含量；提高茎中多糖含量。6-BA浓度为0.5mg·L-1、1.0mg·L-1的处理效果显著优于其它浓度处理，综合考虑，生产中缓解霍山石斛的高温胁迫，推荐使用浓度为0.5mg·L-1的6-BA。

关键词：6-BA；高温；霍山石斛；抗熱性

中图分类号 S79 文献标识码 A 文章编号 1007-7731（2016）11-0038-04

Effects of Different Concentrations of 6-BA on the Heat Resistance of Dendrobidium huoshanness

Wu Jindong

（West Anhui University，Lu'an 237012，China）

Abstract：In order to study the effects of different concentrations of 6-BA on the heat resistance of Dendrobidium huoshanness，the experiment was carried out with annual stems and leaves of biennial Dendrobidium huoshanness.The results showed that，under heat stress （day/night temperature were 35±1℃/25±1℃，respectively），chlorophyll content was decreased constantly，activities of SOD，POD and CAT were improved firstly and then reduced and the peaks were all at the 10th day after heat stress，MDA content was increased constantly in leaves and polysaccharide content was reduced in the stem.6-BA significantly alleviated the hurts of heat stress on Dendrobidium huoshanness.6-BA improved chlorophyll content，activities of SOD，POD and CAT，reduced MDA content in leaves and improved the polysaccharide content in the stem.The effects of two treatments （6-BA concentrations were 0.5mg·L-1、1.0mg·L-1，respectively） were significantly better than other treatments.Considered comprehensively，the 6-BA concentration of 0.5mg·L-1 was recommended in production to alleviate the hurts of heat stress in Dendrobidium huoshanness and improve its quality.

Key words：6-BA；Heat stress；Dendrobidium huoshanness；Heat resistance

霍山石斛（Dendrobidium huoshanness Tang et Cheng），属兰科石斛属植物，又名霍石斛、米斛，产于大别山区安徽霍山及邻近地区，是我国名贵的中药。霍山石斛不仅具有滋阴清热、生津益胃、润肺止咳及清音明目等功效，还可用于降低心率、血压，减慢呼吸、扩张血管及抗血小板凝集，具有抗肿瘤、抗衰老、增强机体免疫力等作用[1]。温度是制约作物产量和品质的主要环境因子，而霍山石斛对生态环境要求严格，需要温暖湿润的生长环境，其生长适温为18～32℃，最适生长期温度为25℃，在5℃以下或35℃以上会停止生长[2]。郝丽丽等[3]、艾娟等[4]研究表明，金钗石斛在25℃条件下植株长势最佳，铁皮石斛在20℃具有更高的多糖含量。近年来，由于温室效应现象的加剧，全球气温不断升高，寻找缓解高温胁迫的有效途径是石斛栽培生产中急需解决的问题。……