The results of changes in photochemical activity parameters and chloroplast pigments in the present study indicated that xanthophylls cycle was induced in leaves of boea hygrometrica when they were dehydrated for 8 days under very weak light condition ( 3u mol . m - 2 . s - 1 ) , xanthophylls cycle may play a photoprotective role in dehydrated boea leaves 为此本研究对牛耳草叶片光系统的光化学活性参数和叶黄素循环色素在脱水复苏过程中的变化进行了分析，结果表明，在极微弱的光强( 3 mol m ~ ( - 2 ) s ~ ( - 1 )下，脱水8天的牛耳草叶片诱导了叶黄素循环，叶黄素循环可能介导了牛耳草叶片脱水过程中的光保护作用。
