桢楠幼树生长和营养元素吸收对镉胁迫的响应及其镉富集特性  

Response of growth and nutrient absorption of Phoebe zhennan saplings to cadmium stress and its bioaccumulation characteristics for cadmium

作　　者：官鹏 铁得祥 胡红玲[1] 陈刚[1] 李闯 李冬豪 邓雯 GUAN Peng;TIE Dexiang;HU Hongling;CHEN Gang;LI Chuang;LI Donghao;DENG Wen(College of Forestry,Sichuan Agricultural University,Chengdu,Sichuan 611130,China)

机构地区：[1]四川农业大学林学院,四川成都611130

出　　处：《西北农林科技大学学报(自然科学版)》2025年第3期10-20,35,共12页Journal of Northwest A&F University(Natural Science Edition)

基　　金：四川省“十三五”农作物育种攻关项目(2016NZ0098-10)。

摘　　要：【目的】分析镉(Cd)对桢楠(Phoebe zhennan)幼树生长和各器官中营养元素含量及分配模式的影响,探讨桢楠对Cd的耐受能力及富集性,以正确选择桢楠的适生立地。【方法】以3.5 a桢楠幼树为试验材料,采用盆栽控制试验,设置0(CK),10,20,30,40和50 mg/kg 6个Cd(以CdCl_(2)形式施入)处理水平,分5次施入,每2月施1次,试验结束后测定不同处理桢楠的叶面积、株高、根系活力和各个器官(叶、枝、主干、运输根、吸收根)的生物量及其N、P、K、Mg、Fe、Cd含量,计算各器官的Cd富集系数(BCF)和不同处理的Cd转运系数(TF),分析桢楠对镉胁迫的响应及其对镉的富集和转运特性。【结果】①当第4次施入CdCl_(2)约15 d后,除CK外,其余Cd处理植株叶缘均出现枯萎现象,且随Cd胁迫的加重其叶缘枯萎面积逐渐增大。②与CK相比,桢楠幼树株高净生长量在Cd处理水平≥20 mg/kg时显著(P<0.05)降低,总生物量、根系活力则是所有Cd处理均受到显著(P<0.05)抑制。③随施Cd量的增加,叶、枝、主干中的N含量总体呈降低趋势,吸收根中的N含量呈先降后增趋势且各处理均显著低于CK,而运输根中的N含量在各处理与CK间均无显著差异;枝和吸收根中的P含量均较CK显著降低,运输根中的P含量在施Cd量≥40 mg/kg时显著降低,而叶片和主干中的P含量在50 mg/kg Cd处理时显著高于CK;运输根中的K含量自20 mg/kg Cd处理开始显著低于CK,其余器官中的K含量在各水平Cd处理下均较CK显著降低;运输根中Mg含量在各水平Cd处理下均较CK增高,其中10,20和50 mg/kg Cd处理显著增高,而各水平Cd处理下其他器官中的Mg含量均与CK无显著差异;除10 mg/kg Cd处理外,其余Cd处理下叶中Fe含量均较CK显著增高,但枝和主干中Fe含量分别在施Cd量大于等于50和40 mg/kg时显著低于CK,而在运输根和吸收根中各Cd处理Fe含量均与CK无显著差异。④随施Cd量的增加,吸收根、叶和枝中的Cd含【Objective】The effects of cadmium(Cd)on the growth of Phoebe zhennan saplings and nutrient content and distribution patterns in various organs were analyzed.In order to select a suitable site for breeding,the Cd tolerance and enrichment of P.zhennan were investigated.【Method】The 3.5-year-old P.zhennan saplings were used as the experimental materials,and the pot control test was used,and 6 Cd(in the form of CdCl_(2))treatment levels were set up at 0(CK),10,20,30,40 and 50 mg/kg,which were applied in 5 times,once every 2 months,and after the experiment,the leaf area,plant height,root activity and biomass of each organ(leaf,branch,trunk,transport root,absorbing root)and the content of N,P,K,Mg,Fe and Cd of different treatments were measured.The Cd bioaccumulation factor(BCF)of each organ and the Cd translocation factor(TF)of different treatments were calculated to analyze the response of P.zhennan to cadmium stress and its enrichment and transport characteristics to cadmium.【Result】①About 15 days after the fourth application of CdCl_(2),the leaf margins of plants treated with Cd,except CK,were all withe-red,and the area of leaf margins withered gradually increased with the increase of Cd stress.②Compared with CK,the net plant height growth of P.zhennan saplings was significantly decreased(P<0.05)when the Cd treatment level was greater than or equal to 20 mg/kg,while the total biomass and root activity were significantly inhibited(P<0.05)by all Cd treatments.③With the increase of Cd application,the N content in leaves,branches and trunk showed a decreasing trend,and the N content in absorbing roots showed a trend of first decreasing and then increasing,and the N content in each treatment was significantly lower than that of CK,while there was no significant difference in N content in transport roots between each treatment and CK.The P content in branches and absorbing roots was significantly lower than that in CK,but the P content in transport roots decreased significantly when the dosage of Cd was

关 键 词：桢楠 镉胁迫 幼树生长 营养元素吸收 镉富集性 

分 类 号：X792.24[环境科学与工程—环境工程] X503.235