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用PAM脉冲调制荧光仪测定叶绿素荧光的变化研究了黄瓜幼苗子叶在PFD为50和100μmolm-2s-1，温度为4、7、10、15℃下的光抑制及其恢复。结果表明，黄瓜幼苗子叶Fv／Fm随着温度的下降和PFD的增加而下降，并且增加等量的PFD在4℃下比在10℃下引起更大的Fv／Fm下降。在黑暗条件下光抑制有轻微恢复，但完士恢复必需光照，且恢复起始时的光照十分重要。DTT可部分抑制叶绿素荧光Fo和Fm的猝灭，且15℃下比在4℃下抑制效果更大。CAP能强烈地加剧光抑制并几乎完全抑制恢复，且10℃下比在4℃下对光抑制的加剧作用更大。冷锻炼提高了黄瓜幼苗抵抗低温先抑制的能力，而CAP对冷锻炼苗比未锻炼苗的低温光抑制具有更大的加剧作用。
Measurement of Chlorophyll Fluorescence with PAM Pulse Fluorescence Spectrometer The photoinhibition and recovery of cucumber seedling cotyledons at PFD of 50 and 100 μmolm-2s-1 at 4, 7, 10 and 15 ℃ were studied. The results showed that the Fv / Fm of cucumber seedling cotyledons decreased with the decrease of temperature and the increase of PFD, and increasing the equivalent amount of PFD caused larger decrease of Fv / Fm at 4 ℃ than at 10 ℃. Light suppression is slightly restored in dark conditions, but light restoration is necessary, and light at the beginning of recovery is very important. DTT can partially inhibit the quenching of chlorophyll fluorescence Fo and Fm, and the inhibitory effect is greater at 15 ℃ than at 4 ℃. CAP strongly intensified photoinhibition and almost completely inhibited the recovery, and aggravated the photoinhibition more strongly at 10 ° C than at 4 ° C. Cold exercise increased cucumber seedlings resistance to low temperature first inhibition, while CAP on cold exercise than non-exercise seedlings with low temperature light inhibition has a greater role in exacerbating.