外源 H2O2处理对两种小麦叶绿素荧光和叶绿素的影响

目的]研究不同浓度H2O2处理对2种小麦幼苗叶绿素荧光和叶绿素的影响。方法]以小麦品种宁春四号和西旱二号幼苗为材料，采用室内水培试验。结果]对于宁春四号，200μmol／LH2O2处理使得初始荧光（FO）、最大荧光（Fm）、PSI处调节性能量耗散的量子产量Y（NPQ）、光化学淬灭（qP）和非光化学淬灭（NPQ）明显低于对照；不同浓度的H2O2处理使得幼苗叶片叶绿素a（Chla）、叶绿素b（Chlb）和叶绿素总量均显著降低。50、100和200μmol／LH3O2处理下西旱二号幼苗叶片Chla含量和F0显著降低，PSI的最大量子产量（Fv/Fm）、实际光化学反应效率（1，（II））、电子传递速率（ETR）、qP和ⅣPQ均增大，而Chlb和叶绿素总量无显著变化。结论]与宁春4号相比，外源H2O2胁迫使西旱2号小麦幼苗叶片PSⅡ反应系统更开放，光合机构的损伤较严重。

Effects of H2O2 oH Chlorophyll Cluorescenceo and Chlorophyll in Wheat

Objective ] To study the effects of different concentration H2O2 treatments on chlorophyll flttorescenceo and chlorophyll of seedlings of two kinds of wheat. Method] With Ningehun 4 and Xihan 2 seedlings as material, hydroponic experiment was conducted. Result] FO, Fro, Y （NPQ）, Photochemical quenching （qP）, Nonphotochemical quenching （NPQ） significantly decreased under 200 μmol/L H2O2 treatment in comparison with the control, but remarkable reductions in Chla, ehlorophyUb and total chlorophyl/was observed in Ningchun under different H2O2 concentration. 50, 100 and 200 μmol/L H2O2 resulted in decreased chlorophyll a content, F0 was observed decreased to different H2O2 concentration, there was an increase of Fv/Fm, Y（ I]）, ETR, qP and NPQ in response to different H2O2 concentration as com- pared with untreated wheat, while no significant changes in chlorophyll b and total chlorophyll. Conclusion] Exogenous H2O2 treatment resuited PS 11 reaction system more open, and photosynthetic apparatus were damaged more in the mine population in Xihan 2 seedlings, in comparison with Ningehun 4 seedlings.