不同施氮量对杂交酸模叶片光合电子流分配的影响  

Effects of Different Nitrogen Application Rate on Allocation of Photosynthetic Electron Flux in Rumex K-1 Leaves

作　　者：李海东[1] 高辉远[2] 

机构地区：[1]山东农业大学生命科学学院,泰安271018 [2]山东农业大学生命科学学院作物生物学国家重点实验室,泰安271018

出　　处：《植物生理与分子生物学学报》2007年第5期417-424,共8页Journal Of Plant Physiology and Molecular Biology

基　　金：国家自然科学基金项目(No.30571125);高校博士点专项基金项目(No.20050434007)资助。~~

摘　　要：研究了不同施氮量对高蛋白含量植物杂交酸模(Rumex patientiaxR.tianschanicus)叶片中总光合电子流和分配在碳同化、光呼吸、Mehler反应以及氮代谢上的光合电子流的影响,并研究了不同施氮量对硝酸还原酶(NR)和谷氨酰胺合成酶(GS)的活性、叶片的蛋白质含量及叶绿素含量的影响。结果表明随着施氮量的增加,硝酸还原酶和谷氨酰胺合成酶的活性都显著提高,同时更多的光合电子流分配到氮代谢和光呼吸。氮代谢所需光合电子流约占总光合电子流的15%～21%。缺氮并没有造成光合电子流向Mehler反应分配的增加。The total photosynthetic electron flux through PSII [Je （PSII）], the electron flux used for carbon assimilation [Je （PCR）], the electron flux used for photorespiration [Je （PCO）], the electron flux used for Mehler reaction [Ja（OE-depend）] and the electron flux used for nitrogen metabolism [Ja （O2-independ）] in leaves of Rumex K- 1, a fodder crop with high protein content, were measured under three levels of nitrogen application （Fig.2）. The nitrate reductase （NR） activity, ghtamine syn- thetase （GS） activity, the leaf protein content, the chlorophyll content （Fig.3）, Pn and φ （PSII） （Fig. 1） and F√Fm （Table 1） were also measured. The results showed that with the increase of nitrogen application, the NR and GS activities increased remarkably （Fig.3） and more electron flux was al- located to nitrogen metabolism as well as photo- respiration （Fig.2）. Nitrogen metabolism and car- bon metabolism competed for energy, and the pro- portion of energy used in nitrogen metabolism to that used in carbon metabolism changed with ni-trogen application rate. The electron flux used for nitrogen metabolism is about 15%-21% of the to- tal electron flux under the three levels of nitrogen application （NO3- 0-30 mmol/L）. Under lower ni- trogen application, though energy used for carbon and nitrogen assimilation remarkably decreased, no significant increase of electron flux allocated to Mehler reaction was observed. The excess ex- citation energy in the leaves under the lower nitro- gen application was efficiently dissipated via other energy dissipation mechanisms to protect the leaves against photo-damage.

关 键 词：光合电子流 氮代谢 光呼吸 能量分配 杂 交酸模 

分 类 号：S54[农业科学—作物学]