低磷胁迫对大花序桉幼苗叶片生理指标的影响  

Effects of low phosphorus stress on physiological characteristics of Eucalyptus coleziana seedling leaves

作　　者：何榜眼 刘世男[1] 杨梅[1] 梁喜献 HE Bang-yan;LIU Shi-nan;YANG Mei;LIANG Xi-xian(Forestry College,Guangxi University,Nanning 530004,China;Xingjian College of Arts and Sciences,Guangxi University,Nanning 530004,China)

机构地区：[1]广西大学林学院,南宁530004 [2]广西大学行健文理学院,南宁530004

出　　处：《西南农业学报》2022年第2期418-424,共7页Southwest China Journal of Agricultural Sciences

基　　金：广西自然科学基金重点项目(2021GXNSFDA196003);广西林业科技项目(推广示范类)(gl2020kt01);广西大学博士启动项目(20190022)

摘　　要：【目的】探究低磷胁迫对大花序桉叶片生理指标的影响,为大花序桉抗低磷机制研究及其苗木推广种植提供参考依据。【方法】设置低磷浓度(0.1 mmol/L)和正常磷磷浓度(1.0 mmol/L)Hoagland营养液对大花序桉无性系1203号和1212号幼苗进行水培,20 d后测定其叶片的保护酶活性、丙二醛(MDA)含量、光合色素含量和叶绿素荧光参数,利用单因素方差分析和Pearson相关系数分析不同磷浓度处理大花序桉幼苗叶片的生理指标。【结果】在低磷处理下,大花序桉无性系1203号和1212号幼苗叶片的MDA含量分别为0.0032和0.0037μmol/g FW,超氧化物歧化酶(SOD)活性分别为18.42和16.25 U/g FW,多酚氧化酶(PPO)活性分别为894.13和1138.00 U/g FW,过氧化物酶(POD)活性分别为579.67和471.33 U/g FW,抗坏血酸过氧化物酶(APX)活性分别为1598.89和688.33 U/g FW,均显著高于正常磷处理(P<0.05);叶绿素总量分别为1.65和1.51 mg/g,类胡萝卜素(Caro)含量分别为0.17和0.12 mg/g,均低于正常磷处理;PSⅡ反应中心初始荧光(F_(o))均为0.082,非光化学淬灭系数(NPQ)分别为1.44和1.35,均高于正常磷处理,最大荧光(Fm)分别为0.37和0.40,可变荧光(F_(v))分别为0.29和0.31,最大光化学量子效率(F_(v)/Fm)分别为0.78和0.79,实际光化学效率(Φ_(PSⅡ))分别为0.31和0.32,均低于正常磷处理。相关分析结果表明,低磷胁迫对大花序桉幼苗各生理指标存在不同程度的影响,特别对叶绿素荧光参数的影响最大。【结论】低磷胁迫会使大花序桉幼苗叶片大量积累MDA,导致叶片组织受到不可逆的损伤,进而引起叶片光合机构功能异常;但大花序桉幼苗能通过对叶片SOD、PPO、POD和APX等保护酶和NPQ的综合调节来减轻低磷胁迫引起的伤害,尤其以PPO和NPQ的调节作用更佳,二者在减轻大花序桉幼苗叶片损害过程中可能发挥着重要作用。[Objective]The present paper aimed to explore the effects of low phosphorus stress on physiological indexes of Eucalyptus coleziana leaves,to provide reference basis for the study of low phosphorus resistance mechanism of E.coleziana and the popularization and planting of seedlings.[Method]The seedlings of E.coleziana clones 1203 and 1212 were hydroponically cultured with Hoagland nutrient solution with low phosphorus concentration(0.1 mmol/L)and normal phosphorus concentration(1.0 mmol/L).After 20 days,the protective enzyme activity,malondialdehyde(MDA)content,photosynthetic pigment content and chlorophyll fluorescence parameters of seedlings of E.coleziana clones 1203 and 1212 were measured,and single-factor analysis of variance and Pearson correlation coefficient were used to analyze the physiological indexes of leaves of E.coleziana seedlings treated with different phosphorus.[Result]Under low phosphorus treatment,the content of MDA in the leaves of clones 1203 and 1212 were 0.0032 and 0.0037 μmol/g FW,the SOD activity were 18.42 and 16.25 U/g FW,the PPO activity were 894.13 and 1138.00 U/g FW,the POD activities were 579.67 and 471.33 U/g FW,the APX activities were 1598.89 and 688.33 U/g FW respectively,which were significantly higher than that of normal phosphorus treatment(P<0.05).The total chlorophyll contents were 1.65 and 1.51 mg/g,and the carotenoid contents were 0.17 and 0.12 mg/g,respectively,which were lower than normal phosphorus treatment.The initial fluorescence(F_(o))of the PSⅡ reaction center both were both 0.082,the non-photochemical quenching coefficients(NPQ)were 1.44 and 1.35,respectively,which were higher than those of normal phosphorus treatment.The maximum fluorescence(F_(m))were 0.37,and 0.40,the variable fluorescence(F_(v))were 0.29 and 0.31,the maximum photochemical quantum efficiency(F_(v)/F_(m))were 0.78 and 0.79,and the actual photochemical efficiency(Φ_(PSⅡ))were 0.31 and 0.32 respectively,which were lower than that of normal phosphorus treatment.The results of correlation an

关 键 词：大花序桉 低磷胁迫 生理指标 保护酶活性 叶绿素荧光参数 

分 类 号：S792.39[农业科学—林木遗传育种]