高温胁迫下半夏倒苗前后光合参数及叶绿素荧光特性的变化

Changes of photosynthesis parameters and chlorophyll fluorescence around sprout tumble of Pinellia ternata under high temperature stress

目的:探讨高温胁迫下半夏倒苗过程中光合作用及叶绿素荧光特性的变化,从而为延缓半夏倒苗提供信息。方法:在半夏植株高15 cm左右时,给予37℃的高温胁迫,于不同的胁迫处理天数分别测定半夏叶片叶绿素含量、光合作用和叶绿素荧光参数等生理指标。结果与结论:随着高温胁迫时间的延长,半夏叶片叶绿素含量、Chla/Chlb、净光合速率(Pn)、气孔导度(Gs)、蒸腾速率(Tr)、最大荧光产量(Fm)、光合电子传递量子效率(ΦPSⅡ)、光系统Ⅱ的原初光能转换效率(Fv/Fm)、光化学淬灭系数(qP)下降,而胞间CO2浓度(Ci)、最小荧光产量(F0)、非光化学淬灭系数(NPQ)上升。

Objective： To study the change of photosynthesis and chlorophyll fluorescence characteristics of Pinellia ternata around sprout tumble.Method： Tubers of P.ternata were cultured firstly at（25±1） ℃ for certain days,and then they were coerced under 37 ℃ stress in the same artificial climate boxes.The chlorophyll contents,photosynthesis and chlorophyll fluorescence during different stages of high temperature stress were measured.Result and Conclusion： After under high temperature stress,the chlorophyll contents,the ratio of chlorophyll a/b,photosynthetic rate（Pn）,stomatal conductance（Gs）,transpiration rate（Tr）,maximum fluorescence（Fm）,quantum yield of PSⅡ（ΦPSⅡ）,intrinsic photochemical efficiency of PSⅡ（Fv/Fm） and the chlorophyll photochemical quenching（qP） decreased,but the intercellular CO2 concentration（Ci）,minimal fluorescence（F0）,the chlorophyll non-photochemical quenching（NPQ） increased.