石光达 康鹏 潘雅清 郭雨辰 王强 李洪明 雷茜

摘要 為明确不同浓度褪黑素喷施对干旱复水条件下玉米幼苗生长及生理特性的影响。采用室内盆栽培养试验，以“沈玉21”玉米幼苗为材料，将其进行7 d干旱胁迫（30% FWC）后复水处理，喷施不同浓度褪黑素，以探求外源褪黑素对玉米幼苗干旱后复水的影响。结果表明，干旱胁迫严重抑制玉米幼苗的生长，复水条件下喷施褪黑素，促进了植株的生长和根系发育，提高了叶绿素的生物合成和光合作用;同时，外源褪黑素提高了植株可溶性糖、可溶性蛋白和脯氨酸等渗透调节物质的积累，抑制了MDA的产生，提高了SOD、POD和CAT的活性;此外，褪黑素还能提高干旱复水条件下玉米叶片的AsA/DHA、GSH/GSSG，抑制ROS大量产生，减少胁迫对植株细胞膜系统的伤害;其中，外源褪黑素浓度为50～100 μmol/L时，调控效果最佳。总之，外施褪黑素可通过调节逆境下植物细胞的信号传导，以此在分子水平调控植株对干旱胁迫的生理响应，促进植物生长、提高渗透调节及抗氧化的能力，有效减缓胁迫对植株造成的负面影响。

关键词 干旱复水;褪黑素;玉米;生理特性

中图分类号 S513  文献标识码 A

文章编号 0517-6611（2021）24-0060-07

doi：10.3969/j.issn.0517-6611.2021.24.014

Effects of Exogenous Melatonin on Plant Growth and Physiology Characteristics of Maize Seedling under Drought-rewater Treatment

SHI Guang-da1，KANG Peng1，2，PAN Ya-qing3 et al （1.College of Biological Sciences and Engineering，North Minzu University，Yinchuan，Ningxia 750021;2.Ningxia Key Laboratory of Microbial Resources Development and Applications in Special Environment，Yinchuan，Ningxia 750021;3.School of Agriculture，Ningxia University，Yinchuan，Ningxia 750021）

Abstract In order to determine the effects of different concentrations of melatonin on the growth and physiological characteristics of maize seedlings under drought-rewater conditions.Maize seedlings of Shen Yu 21 were treated with water rehydration after 7 days of drought stress （30% FWC）.Melatonin of different concentrations was sprayed during this period to study the effect of exogenous melatonin on the rehydration of maize seedlings after drought.The results showed that drought stress seriously restraint in the growth of maize seedlings，and melatonin spraying under the condition of rehydration promoted the growth and root development of maize plants，as well as chlorophyll biosynthesis and photosynthesis.Meanwhile，exogenous melatonin increased the accumulation of osmotic regulatory substances such as soluble sugar，soluble protein and proline，reduced the content of MDA，and improved the activity of SOD，POD and CAT.In addition，melatonin can enhance the AsA/DHA.GSH/GSSG ratios in maize leaves under drought-rewater conditions，alleviated the damage of plant cell membrane system.In brief，when the exogenous melatonin concentration was 50-100 μmol/L，the regulation effect was optimum.In conclusion，exogenous melatonin could regulate the physiological response of plants to drought stress at the molecular level by regulating the signal transduction of plant cells under stress，so as to promote plant growth，improve the ability to regulate osmosis and antioxidant，and effectively mitigate the negative effects of stress on plants.

Key words Drought-rewater;Melatonin;Maize;Physiology characteristics

基金项目

宁夏回族自治区大学生创新创业训练计划项目（S2020-11407-028）;北方民族大学生创新创业训练计划项目（2021-XJ-SK-019）;北方民族大学中央高校基本科研业务费专项资金资助（2019XYZSK04）。

作者简介 石光达（1999—），男，内蒙古通辽人，从事植物逆境生理生态研究。*通信作者，副教授，硕士，从事植物生态学研究。……