桑树叶片光合诱导对光强转换的响应  

Response of photosynthetic induction to irradiance transition in mulberry leaf

作　　者：胡彦波[1] 许楠[1] 包卓[1] 张晓松[1] 孙广玉[1] 

机构地区：[1]东北林业大学生命科学学院,哈尔滨150040

出　　处：《中国生态农业学报》2010年第4期799-803,共5页Chinese Journal of Eco-Agriculture

基　　金：国家自然科学基金项目(30771746);黑龙江省重点科技攻关项目(GB07B306);哈尔滨市重点科技攻关项目(2004AA6CN142)资助

摘　　要：在温室条件下,以桑树品种"蒙古桑"幼苗为试验材料,应用气体交换和叶绿素荧光测定技术,研究了光强转换过程中桑树叶片的光合诱导响应。结果表明:光强由黑暗或低光转换到高光时,桑树叶片净光合速率需要10min的光诱导才能达到稳定状态,其中1～2min之内的光诱导较快(快相诱导),8～10min诱导较慢(慢相诱导)。当光强由黑暗转到高光时,光量子转化效率的诱导过程滞后于光合碳同化诱导过程;当光强由高光转到低光或黑暗时,桑叶的光合诱导平衡速率快于光强由低光或黑暗转到高光时的平衡速率。说明光量子转化效率的光诱导受碳同化诱导过程的限制,光量子转化效率的诱导主要通过调控PSⅡ开放的反应中心比例来实现。Using ＂Menggusang＂ mulberry （Morus alba L.） seedling grown under greenhouse conditions in Heilongjiang Province, we analyzed photosynthetic induction responses to irradiance transitions via gas-exchange and chlorophyll fluorescence techniques. Results show that 10 min photosynthetic induction is needed for the photosynthetic rate （Pn） of mulberry leaf to reach stable state under the sudden irradiance transition from dark/low irradiance （LI） to high irradiance （HI）. A biphasic photosynthetic response is evident — rapid phase （1～2 min） and slow phase （8～10 min）. When irradiance is transited from LI to HI, induction of photosynthetic quantum conversion efficiency falls behind the photosynthetic CO2 assimilation. When irradiance is changed from high to low/dark, Pn faster approaches steady-state compared to the irradiance transfer from low/dark to high. This indicates that induction efficiency of quantum conversion is limited by photosynthetic CO2 assimilation following increase in irradiance. Induction efficiency of photosynthetic quantum conversion may therefore be regulated by the proportion of open PSⅡ reaction centers.

关 键 词：光强转换 桑树 碳同化诱导 光合诱导 

分 类 号：Q945.1[生物学—植物学]