铅胁迫下硅对香樟幼苗生理的调控作用  

Regulation of Silicate on the Physiology of Cinnamomum camphor Seedlings under Lead Stress

作　　者：周倍竹 杨秀玲 王凌晖[1] 唐新瑶 卢立国 ZHOU Beizhu;YANG Xiuling;WANG Linghui;TANG Xinyao;LU Liguo(Guangxi University,Nanning,Guangxi 530004,China;Yulin Normal University,Yulin,Guangxi 537006,China)

机构地区：[1]广西大学林学院,广西南宁530004 [2]玉林师范学院,广西玉林537006

出　　处：《热带农业科学》2022年第12期54-60,共7页Chinese Journal of Tropical Agriculture

基　　金：国家自然科学基金(No.31360174);广西国有钦廉林场林业科技项目(No.钦廉科字2017-1号);广西林业科技项目(No.桂林科字[2012]第17号)。

摘　　要：为探究香樟对铅胁迫的生理响应及外源硅对香樟耐铅性的影响,以香樟幼苗为试材,研究不同浓度(0、500、1000、2000 mg/kg)铅胁迫及不同浓度(0、1000和2000 mg/kg)硅对香樟幼苗光合特性、渗透调节物质含量及抗氧化酶活性的影响。结果表明:500 mg/kg铅胁迫增强了香樟光合作用的能力,1000、2000 mg/kg铅胁迫抑制了光合作用,且铅浓度越高,抑制作用越严重;铅胁迫提高了丙二醛含量、渗透调节物质含量和抗氧化酶活性,且铅浓度越高,其增量越大。在相同铅、不同硅处理下,1000 mg/kg硅的处理显著缓解了铅对香樟的胁迫效应,增大了叶绿素含量,提高光合能力,促进生成更多渗透调节物质帮助维持体内水势平衡,并减少丙二醛的产生,显著提高抗氧化酶活性,进而有效减轻铅胁迫导致的过氧化损伤;而2000 mg/kg硅的处理表现相反,严重削弱了香樟幼苗抵御铅胁迫的能力。综上所述,香樟在2000 mg/kg铅胁迫下能够生长正常,1000 mg/kg硅可作为香樟在铅胁迫下的缓解剂,有助于保证香樟在铅污染地区的景观效果与生态效益。In order to investigate the physiological response of Cinnamomum camphora to lead stress and the effect of exogenous silicon on the lead tolerance,C.camphora seedlings was used as the test material.Effects of different levels lead stress(0,500,1000 and 2000 mg·kg?1)and effects of different concentrations of silicon(0,1000 and 2000 mg·kg?1)on photosynthetic characteristics,osmotic regulation substance content and antioxidant enzyme activity of C.camphora seedlings.The results showed that 500 mg·kg?1lead stress enhanced the photosynthesis ability of C.camphora seedings,1000 mg·kg?1and 2000 mg·kg?1lead stress inhibited photosynthesis,the higher the lead centration was,the more serious the damage to C.camphora seedings;The lead stress enhanced Malondialdehyde content,osmolyte’s content and antioxidant enzyme activity,and the higher the lead concentration was,the greater the increment.Under the same level lead stress and different concentrations of silicon,the treatment of 1000 mg·kg?1silicon significantly alleviated the stress effect of lead on C.camphora,increased chlorophyll content,improved photosynthetic capacity,promoted the production of more osmotic regulation substance,helped maintain the balance of water potential in the cell,Malondialdehyde content was significantly reduced while antioxidant enzyme activity was significantly improved,thereby effectively reducing the peroxidative damage caused by lead stress;while the treatment of 2000 mg·kg?1silicon showed the opposite,which seriously weakened the ability of C.camphora seedlings to resist lead stress.In summary,camphor can grow normally under 2000 mg·kg?1lead stress,and 1000 mg·kg?1silicon can be used as a mitigation agent for Camphor seedings under lead stress,which helps to ensure the landscape effect and ecological benefits of C.camphora in lead-contaminated areas.

关 键 词：香樟 重金属 硅 铅胁迫 生理特性 

分 类 号：S792.23[农业科学—林木遗传育种]