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作 者 ：李 宁,王美月,孙 锦,束 胜,郭世荣*,王军伟,孙洪助

期 刊 ：西北植物学报 2013年 7期 页码：1395~1402

关键词：24-表油菜素内酯(EBR)；弱光胁迫；番茄幼苗；光合作用；非气孔限制因素；

Keywords:24-epibrassinolide（EBR）, low light stress, tomato seedlings, photosynthesis, non-stomatal limitation,

摘 要 ：以弱光敏感型番茄品种‘基尔斯’为试验材料,采用营养液栽培方式,研究了外源24-表油菜素内酯（24-epibrassinolide,EBR）对弱光(80 μmol·m^-2·s^-1)胁迫下番茄幼苗生长、气体交换参数、叶绿素荧光参数、叶绿素含量、抗氧化酶活性和MDA含量的影响。结果显示,弱光胁迫显著影响番茄幼苗的生长和相关生理指标。而弱光下叶面喷施EBR 15 d后,番茄幼苗的茎粗、地上部鲜重、干重、壮苗指数分别显著升高15.8%、29.3%、79.0%、114.5%,净光合速率（P_n）、气孔导度（G_s）、蒸腾速率（T_r）分别显著升高34.1%、46.3%、35.9%,叶绿素荧光参数F_v/F_m、Ф_PSⅡ、ETR分别升高21.0%、15.4%、16.7%,SOD、POD、CAT和APX活性分别升高16.7%、31.8%、32.7%、51.2%,株高、叶面积、胞间CO₂浓度（C_i）、叶绿素总量、MDA含量分别下降9.8%、13.9%、0.9%、13.2%、19.5%。研究表明,适量外源EBR可以通过增强保护酶系统的活性来减轻弱光胁迫造成的膜脂过氧化伤害,有效解除弱光胁迫下番茄幼苗光合作用减弱的非气孔限制因素,维持光合活性,促进幼苗生长。

Abstract:With low-light sensitive tomato variety ‘Jiersi’ as the tested material,we investigated the effects of exogenous 24-epibrassinolide（EBR） on the growth,gas exchange parameters,chlorophyll fluorescence parameters,chlorophyll content,anti-oxidative enzyme activities and MDA content of tomato seedlings under low light stress by hydroponic culture.The research showed that there were significant effects on the growth and physiological function under low light.However,in the treatment of foliar spraying EBR for 15 days under low light,the stem diameter,shoot fresh weight,dry weight and healthy index of tomato seedlings were significantly increased by 15.8%,29.3%,79.0% and 114.5%,respectively；Net photosynthetic rate（P_n）,stomatal conductance（G_s） and transpiration rate（T_r） were significantly enhanced by 34.1%,46.3% and 35.9%,respectively；Chlorophyll fluorescence parameters F_v/F_m,Ф_PSⅡ and ETR were raised by 21.0%,15.4% and 16.7%,respectively；SOD,POD,CAT and APX activities were increased by 16.7%,31.8%,32.7% and 51.2%,respectively.The plant height,leaf area,intercellular CO₂ concentration（C_i）,chlorophyll content and MDA content were decreased by 9.8%,13.9%,0.9%,13.2% and 19.5%,respectively.Hence,it was indicated that appropriate amount of exogenous EBR could mitigate lipid peroxidation injury by strengthening the protective enzymatic system activity,alleviate non-stomatal limitation which inhibited photosynthetic function under low light,and maintain the photosynthetic activity,promote growth.

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