MPEC: an important gene in the chlorophyll biosynthesis pathway in photosynthetic organismsInstitute of Experimental Botany - Tập 46 - Trang 321-328 - 2008
H. -H. Liu, C. -C. Zheng
One of the least understood enzymatic steps in chlorophyll biosynthesis is the formation of isocyclic ring, which is catalyzed by the Mg-protoporphyrin IX monomethyl ester (MgPME) cyclase that is involved in the conversion of MgPME to protochlorophyllide. Several genes encoding part of this enzyme have been identified and functional analysis of them has been performed. The enzyme plays important r...... hiện toàn bộ
Seasonal Variation of Photoinhibition of Photosynthesis in Bark from Populus Tremula L.Institute of Experimental Botany - Tập 35 - Trang 411-417 - 1998
K.A. Solhaug, J. Haugen
In the bark of Populus tremula L. photochemical efficiency of photosystem 2 (PS2) determined as Fv/Fm decreased during winter. The strongest reduction was found after cold periods. The degree of reduction depended on irradiance since the lowest levels of Fv/Fm were found on the sun-exposed side of the stem and below thin phellem. Therefore, photoinhibition was partly responsible for the reduction ...... hiện toàn bộ
A new viewpoint to understand the response of leaf dark respiration to elevated CO2 concentrationInstitute of Experimental Botany - Tập 45 - Trang 510-514 - 2007
Y.-Z. Qiao, Y.-B. Zhang, K.-Y. Wang, Y.-P. Wang, Y. Xu, Q.-C. Li
By investigating the R
D-C
a (dark respiration rate-atmospheric CO2 concentration) and P
N (net photosynthetic rate)-C
a curves of bamboo (Fargesia denudata) and poplar (Populus cathayanna), we found that: (1) the minimal R
D was close to ambient CO2 concentration, and the elevat...... hiện toàn bộ
Xanthophyll cycle activity in detached barley leaves senescing under dark and lightInstitute of Experimental Botany - Tập 43 - Trang 117-124 - 2005
M. Špundová, K. Strzałka, J. Nauš
Senescence-induced changes in the xanthophyll cycle activity and chlorophyll (Chl) fluorescence parameters were compared in detached barley (Hordeum vulgare L.) leaf segments kept for 6 d in darkness or under continuous “ white light” (90 μmol m−2 s−1). Before detachment of the leaf segments, the plants were grown at periodic regime [12 h light (90 μmol m−2 s−1)/12 h dark]. The de-epoxidation stat...... hiện toàn bộ
Utilization of Photosynthetically Fixed 14CO2 into Alkaloids in Relation to Primary Metabolites in Developing Leaves of Catharanthus roseusInstitute of Experimental Botany - Tập 42 - Trang 469-472 - 2004
N.K. Srivastava, A. Misra, A.K. Srivastava, S. Sharma
Partitioning of current photosynthates towards primary metabolites and its simultaneous incorporation in leaf alkaloids was investigated in developing leaves of medicinally important Catharanthus roseus. Of the total 14CO2 assimilated, the leaves at positions 1–6 fixed 8, 22, 25, 19, 13, and 8 %, respectively, and stem 3 %. Leaf fresh mass, chlorophyll content, and CO2 exchange rate increased up t...... hiện toàn bộ