低钾胁迫下马铃薯植株光合机构响应特性  

Response characteristic of photosynthetic apparatus of potato plants under low-potassium stress

作　　者：乔建磊[1] 于海业[2] 肖英奎[1] 张艳平[1] 王淑杰[1] 

机构地区：[1]吉林大学生物与农业工程学院,长春130022 [2]吉林大学仿生工程教育部重点实验室,长春130022

出　　处：《吉林大学学报（工学版）》2011年第2期569-573,共5页Journal of Jilin University:Engineering and Technology Edition

基　　金：'863'国家高技术研究发展计划项目(2007AA10Z203);吉林省科技发展计划项目(20090566);长春市科技支撑计划项目(09KZ22)

摘　　要：通过不同供钾水平栽培试验,分析了低钾胁迫下马铃薯植株光合机构的响应机制,并探讨了叶片光合参数之间的内在联系。结果表明:在低钾胁迫下,马铃薯叶片中叶绿素a、叶绿素b和类胡萝卜素的含量都明显下降,但低钾胁迫对叶绿素a与叶绿素b含量的比值影响不大,在整个处理期间均无显著差异(P>0.05);低钾胁迫下马铃薯叶片的可变荧光Fv、PSⅡ光化学效率以及潜在活性均有所下降,其中可变荧光Fv的下降是由初始荧光F0的增加和最大荧光Fm的减小所致;在低钾胁迫的初期,马铃薯叶片净光合速率Pn的下降主要是由气孔限制引起,但随着胁迫时间的进一步延长,非气孔限制也逐渐成为Pn下降的重要原因;非直角双曲线Farquhar模型能够较好地描述低钾胁迫下马铃薯植株叶片的光合光响应特性,各胁迫时期叶片Pn-PAR拟合曲线的决定系数均在0.92以上,且拟合分析结果表明低钾胁迫下马铃薯叶片的表观量子效率AQY及表观最大光合速率Pmax均明显下降,但钾素水平的变化对光补偿点LCP和暗呼吸速率Rd的影响并不显著。The response characteristic of photosynthetic apparatus of potato plants under low-potassium stress was analyzed,and the internal relations among the photosynthetic parameters were investigated.Results show that the contents of chlorophyll a,chlorophyll b and carotenoids in leaves decrease under low-potassium stress.However,the effect of the content ratio of chlorophyll a/b was not obvious,that there was no significant difference during the treatment period（P〉0.05）.Variable fluorescence（Fv）,PSII photochemical efficiency and potential activity in leaves under low-potassium treatment were lower than those in control group.The drop in Fv was due to the increase in initial fluorescence（F0） and the decrease in the maximum fluorescence（Fm）.In the early stage of low-potassium stress,the drop in the net photosynthetic rate Pn was mainly induced by the stomatal limitation.With further extension of the stress time,the non-stomatal limitation gradually became a main factor for the drop in Pn.The response characteristic of photosynthesis of potato leaves under low-potassium stress can be described by the non-orthogonal hyperbolic Farquhar model.The coefficient of determination of Pn-PAR response curve in each stage was higher than 0.92.The fitting analysis indicated that both the Apparent Quantum Yield（AQY） and the maximum apparent photosynthetic rate（Pmax） decreased obviously.However,the effects of potassium concentration on Light Compensation Point（LCP） and Dark Respiration Rate（Rd） were not significant.

关 键 词：钾素 胁迫 马铃薯 光合生理 响应特性 

分 类 号：S143[农业科学—肥料学]