IAA及KCN在黄瓜子叶离体叶绿体氧化还原作用过程中的相互作用

ＩＡＡ对于不同时期的叶绿体ＤＣＰＩＰ光还原均有促进效应。而对叶绿体的放氧效率的促进则随子叶叶岭的增长而下降至零。ＣＮ＾－（１０＾－３ｍｏｌ／Ｌ）存在时不同程度地抑制叶绿体的ＤＣＰＩＰ光还原和氧化放氧。而ＩＡＡ（１０＾－５，１０＾－４ｍｏｌ／Ｌ）则能消除ＣＮ＾－的抑制作用而仅表现ＬＡＡ原有的促进作用。同时，ＩＡＡ可以释放照光和不照光条件下ＫＣＮ对离体叶绿体分解外源Ｈ２Ｏ２的抑制。叶绿体光系统的光还原

The action and the interaction of IAA and KCN during the photoreduoxidation of cucumber cotyledon chloroplasts

Purified cucumber cotyledon chloroplasts were treated with IAA (<10 -4 mol/L) and/or KCN (10 -3 mol/L).IAA would promote the DCPIP photoreduction by the chloroplasts from 6 d and 16 d cotyledon.But the promotion to the oxidable oxygen release was less and would decline gradually to as far as zero when the cotyledon became older.So there was a disagreement between the promotion levels of the DCPIP photoreduction and O 2 release.A similar disagreement also existed especially on the 16 d cotyledon chloroplasts.KCN would depress both the DCPIP photoreduction and the photosynthetic O 2 release by the chloroplasts from 6 d and 16 d cotyledon.But IAA could almost totally reverse the depression and demonstrated its original promotion.It is concluded that the photoreduction and the O 2 release could be separated on time by accumulating certain intermediate,probably H 2O 2.IAA could release the KCN depress on the H 2O 2 decomposition by the chloroplasts but could not promote it.