烟草光合作用对低温的响应  

Responses of Photosynthesis to Different Low Temperatures in Tobacco Seedlings Leaves

作　　者：易建华 孙在军 

机构地区：[1]长沙卷烟厂技术中心,湖南长沙410014

出　　处：《作物学报》2004年第6期582-588,共7页Acta Agronomica Sinica

基　　金：湖南省烟草专卖局重点课题项目 ( 0 1 0 12 )

摘　　要：研究了低温对烟苗叶片光合特性的影响。用CIRAS 1光合系统测定了各项光合指标 ,结果表明 :( 1)在 16℃、8℃、3℃条件下 ,净光合速率 (Pn)、表观量子效率 (AQY)、羧化效率 (CE)、RuBP最大再生能力随温度的降低显著下降 ,在8℃、3℃条件下发生了低温光抑制现象 ;低光强下 ,温度对Pn 的影响小 ,温度对Pn 的效应随光强的增大而增大 ,当光强达到 4 0 0 μmol·m-2 ·s-1后 ,Pn 基本由温度决定。 ( 2 )经 3℃低温处理 72h ,其后续影响表现为叶片RuBP最大再生能力、CE、气孔导度、胞间CO2 浓度显著下降 ,AQY略有下降 ,Pn 表现为可逆下降。 ( 3)经 8℃处理 72h ,其后续作用对叶片Pn影响不大。Effects of low temperatures on photosynthesis in the leaves of pot cultured tobacco seedlings were studied with a CIRAS 1 photosynthetic system. The results were as follows: (1)Net photosynthetic rate( P n), apparent quantum yield(AQY), carboxylation efficiency(CE) and the maximum rate of RuBP regeneration were declined with the decrease of temperature from 16℃ to 3℃; chilling induced photoinhibition of photosynthesis was observed at 8℃ and 3℃. Under low light intensity, photosynthesis was little affected by temperature, however it was remarkably affected by the temperature when light was above 400 μmol·m -2 ·s -1 . The higher value of P n should occur at higher temperature combined with higher light intensity. (2) Subsequent effect of chilling treatments on photosynthesis was remarkable. After 72 h treatment at 3℃, the maximum rate of RuBP regeneration, stomatal conductance ( G s), intercellular CO 2 concentration ( C i) and CE were declined significantly , but no obvious changes were observed in AQY. The reversible decline of P n was observed, the depressed photosynthesis was nearly completely recovered at 14℃ for 1 d. After 72 h treatment at 8℃, no remarkable changes were observed in the photosynthetic characteristics.

关 键 词：烟草 光合作用 低温光抑制 低温侵害 

分 类 号：S572[农业科学—烟草工业]