摘要
以多年生浮水植物荇菜(Nymphoides peltata)为实验植物,人工配制氯化钠浓度为0.00 mol/L、0.05 mol/L、0.10 mol/L、0.15 mol/L和0.20 mol/L的水,用于沉水栽培荇菜幼苗;在实验期间,测定荇菜植株的根茎形态特征参数、叶片的光合气体交换参数和叶绿素荧光参数,分析盐胁迫下荇菜植株的耐受性和光合特性。研究结果表明,在实验的第16天,在氯化钠浓度为0.15 mol/L的水体中的荇菜植株还在生长,但是其地上部损伤较大,地下部长势略差,地下茎仍然可以克隆扩展,因此,荇菜植株对盐胁迫具有一定的耐受性;在氯化钠浓度为0.20 mol/L的水体中的荇菜植株地上部基本死亡,地下根系也受到严重损伤;实验的第1天至第7天,当水体中的氯化钠浓度大于0.10 mol/L时,荇菜叶片的光合作用就会被显著抑制,随着水体中氯化钠浓度的增大,荇菜叶片的胞间CO浓度总体上在增大,荇菜叶片的蒸腾速率和气孔导度无明显变化;实验的第3天至第7天,不同盐度水体中的荇菜叶片的光系统Ⅱ实际光化学量子产量和光合电子传递速率都小于淡水水体中的荇菜叶片,而且随着水体中氯化钠浓度的增大,荇菜叶片的光系统Ⅱ实际光化学量子产量和光合电子传递速率都在不断减小。荇菜具有一定的耐盐性,盐胁迫主要通过影响荇菜叶片光系统Ⅱ的光合活性、光合电子传递速率和CO同化能力,进而影响荇菜的光合作用和生物量积累。
Nymphoides peltata,a perennial floating-leaved plant,was used as experimental material.To analyze the physiological responses to salt stress,different concentrations of NaCl solutions,including 0.00 mol/L,0.05 mol/L,0.10 mol/L,0.15 mol/L and 0.20 mol/L,were prepared for submerged cultivation of Nymphoides peltata.Then rhizome morphological parameters,photosynthetic gas exchange parameters and fluorescence parameters of leaves were further analyzed under salt stress to investigate the salt tolerance and photosynthetic characteristics.In general,the results indicated that Nymphoides peltata has certain tolerance to salt stress,and it can survive and maintain continuous growth under 0.15 mol/L NaCl treatment.With this concentration,significant morphological damage of floating leaves were observed,however,the underground rhizomes still kept the capacity for clonal integration,although the rhizomes were physically affected by salt stress.When NaCl concentration was increased to 0.20 mol/L,the aboveground leaves slowly decayed,and underground rhizomes were also seriously damaged.As the results showed,from day 1 to day 7,salt stress with concentration over 0.10 mol/L,had a significant inhibitory effect on the photosynthesis of leaves.The intercellular COconcentration increased with the raise of NaCl concentration,while the transpiration rate and stomatal conductance had no significant changes.From day 3 to day 7,actual photochemical quantum yield of photo systemⅡand photosynthetic electron transport rate significantly decreased under salt-treatment comparing with control plants,and the decline trend exacerbated with the increase of salt concentration.In a word,this study identified that Nymphoides peltata has certain salt tolerance,and salt stress may inhibit photosynthesis and biomass accumulation associating with the photosynthetic activity of photo systemⅡ,electron transfer efficiency and COassimilation ability.
作者
杜凤凤
刘晓静
陈少周
李乃伟
姚东瑞
DU Fengfeng;LIU Xiaojing;CHEN Shaozhou;LI Naiwei;YAO Dongrui(Jiangsu Engineering Research Center f Aquatic Plant Resources and Water Environment Remediation,Institute of Botany,Jiangsu Province and Chinese Academy of Sciences,Nanjing 210014,Jiangsu,P.R.China;Jiangsu Key Laboratory for the Research and Utilization of Plant Resources,Institute of Botany,Jiangsu Province and Chinese Academy of Sciences,Nanjing 210014,Jiangsu,P.R.China)
出处
《湿地科学》
CSCD
北大核心
2022年第4期565-572,共8页
Wetland Science
基金
江苏省林业科技创新与推广项目(LYKJ[2021]32)
省属公益类科研院所自主科研课题(JSPKLB202035)资助。
关键词
荇菜
盐胁迫
克隆
叶片
光合特性
Nymphoides peltata
salt stress
clone
leaf
photosynthetic characteristics
