Study On Photoinhibition And Preventing Photoinhibition From Damaging In Leaves Of Capsicum Annuum L.

Using two different cold sensitive varieties of pepper seedlings as experient materials. The photoinhibition character treated with low temperature and moderate lingt insensity and the mechanism of photoinhibition-resistant treated with normal temperature and strong ling intensity were studied. The main experiment results were that:1. Dealed with the light intensity of 300umol·m^-2·s^-1 and 15℃/5℃low temperature, the Fv/Fm,ΦPSⅡ,qP,Fv′/Fm′,Pn,AQY and CE of two varieties pepper leaves all reduced gradually, LCP increased gradually. It showed that under low temperature, photoinhibition was happened in pepper seedlings leaves, photochemical efficiency reduced. Photoinhibition was increased gradually with the extension of time. In the whole treatment, the all targets of Xiangyan No.16 were better than Xiangyan No.1. It showed that the daptability of Xiangyan No.16 was stranger than Xiangyan No.1 durig the treatment.2. When pepper leaves were treated with the light intensity of 1600μmol·m^-2·s^-1, the AQY,Fm and Fv/Fm all reduced substantially and photoinhibition was happened.3. When pepper leaves which were treated with DTT. SM and NaHSO3 were lightened in 1600μmol·m^-2·s^-1, the AQY, qP,ΦPSⅡand Fv/Fm all reduced evidently, qN increased evidently. There was no remarkable difference between SM, NaHSO3 and CK. The change extent dealed with DTT was bigger than CK. There was no remarkable difference between SM in the time of revival , the revival of Fv/Fm dealed with NaHSO3 and CK. The revival effect which was dealed with DTT was weak and was evidently lower than CK.4. When pepper leaves which were treated with DTT,SM and NaHSO3 were lightened in 1600umol·m^-2·s^-1, the MDA content, the activity of APX, POX were all bigger than CK. The activity of SOD was evidently lower than CK. The MDAcontent, the activity of APX, POD treated with DTT were higher remarkably than that treated with SM and NaHSO3.5. Lutein circulation mechanism which was inhibited by DTT treatment was probably the main mechanism of broken ring of Tabasco denfense of peppers. The role of D1 Pr's reversible effect in losing work and light respiration in photoinhibition-resistant of pepper was less.