叶面喷施6-BA对高温胁迫下甜椒幼苗生长和叶片生理生化指标的影响  

Effect of Foliar-spraying 6-BA on the Growth and Physiological and Biochemical Indexes of Sweet Pepper Seedlings under High Temperature Stress

作　　者：刘凯歌[1,2] 朱月林[1] 郝婷[1] 宋云鹏[2] 龚繁荣[2] 

机构地区：[1]南京农业大学园艺学院,南京210095 [2]上海市农业科学院园艺研究所、上海市设施园艺技术重点实验室,上海201403

出　　处：《西北植物学报》2014年第12期2508-2514,共7页Acta Botanica Boreali-Occidentalia Sinica

基　　金：上海市科学技术委员会科研计划项目(13391901100)

摘　　要：以‘P13201’甜椒品种为材料,在光照培养箱内采用营养液栽培法,研究了叶面预喷施不同浓度6-BA(5、10、20、50μmol/L)溶液对高温胁迫(40℃/30℃昼/夜)下甜椒幼苗的生长及生理生化指标的影响,探讨缓解甜椒高温胁迫的最佳6-BA浓度。结果显示:(1)高温胁迫致使甜椒幼苗的各生长指标及叶绿素含量显著下降,且10μmol/L 6-BA处理下的株高、茎粗、地上干重、根干重与常温对照(28℃/18℃昼/夜)差异不显著,其幼苗的地上鲜重、根鲜重、叶绿素a、叶绿素b及叶绿素总含量在各处理中降幅也最小。(2)高温胁迫下甜椒幼苗叶片的PSⅡ实际光化学量子产量(Yield)、PSⅡ实际光化学效率(ФPSⅡ)、PSⅡ最大光化学效率(Fv/Fm)显著下降,非光化学猝灭(NPQ)显著升高;相比其他处理组,10μmol/L 6-BA溶液处理下的各荧光参数变化幅度最小,特别是NPQ与对照差异不显著。(3)甜椒叶片中O-·2产生速率、抗氧化酶(SOD、APX、POD)活性、丙二醛(MDA)含量及相对电导率受高温胁迫后显著增大,但10μmol/L 6-BA溶液处理下O-·2产率、MDA含量及相对电导率显著小于T0处理(蒸馏水+高温)下的各值,而其SOD、APX、POD活性则表现相反,相比T0处理,显著升高了50.5%、79.4%、50.3%。研究表明,高温显著抑制了甜椒幼苗正常生长,致使叶片中各抗逆生理生化指标变幅大增,而叶面喷施适宜浓度的6-BA有利于高温胁迫下抗氧化酶活性的升高及光能的捕获与转换,有效缓解高温胁迫伤害,维持甜椒幼苗的正常生长,并以10μmol/L 6-BA溶液处理效果最好。The experiment was carried out by sweet pepper cultivar ＇P13201＇ in light growth incubator and nutrient solution to investigate the effects of pre-spraying different concentrations of 6-BA（5,10,20,50 μmol/L） on the growth and physiological and biochemical indexes of the sweet pepper seedlings under high temperature stress（40 ℃/30 ℃ day/night）. The results showed that： （1）Growth index and chlorophyll content were significantly descended under high temperature stress, while plant height, stem diameter, shoot and root dry matter weight of sweet pepper treated with 10 μmol/L 6-BA concentration had no sig- nificant difference compared with the control check（CK）,reduction of shoot and root fresh matter weight, contents of chlorophyll a, chlorophyll b and total chlorophyll of sweet pepper with this concentration were the smallest as well, among all the treatments. （2）Actual photochemical yield of PS ]I （Yield）, actual photo- chemical efficiency of PSl] （~PsH）,optimal photochemical efficiency of PS 1I in the dark（Fv/Fm） were sig- nificantly decreased under heat stress,while the non-photochemical fluorescence quenching（NPQ） showed a reverse trend. The extent of variation of four fluorescence parameters mentioned above in leaves of sweet pepper treated with 10 ~mol/L 6-BA were the lowest among the all treatment groups,especially NPQ,dis- playing no significance with CK. （3）Affected by high temperature stress, the productivity of 02＂ , activities of superoxide dismutase （SOD）, ascorbic acid peroxidase （APX）, peroxidase （POD） and malondialdehyde （MDA） content, relatively conductivity rate increased significantly. However, the productivity of 02＂. MDA content and relatively conductivity rate in leaves of sweet pepper treated with 10 ~mol/L 6-BA were signifi- cantly smaller than those of To treatment group（distilled water＋ high temperature）. The activities of SOD, APX and POD revealed a remarkably increased tendency,namely,to rise by 50.5%,79.4% and

关 键 词：甜椒 6-BA 高温胁迫 生长 抗氧化酶活性 叶绿素荧光参数 

分 类 号：Q945.78[生物学—植物学]