Čeština
EnglishPhotosynthesis and water relations in transgenic tobacco plants with T-DNA carrying gene 4 for cytokinin synthesis.
Čatský J., Pospíšilová J., Macháčková I., Wilhelmová N., Šesták Z.
BIOLOGIA PLANTARUM 35: 393-399, 1993
Klíčová slova: chlorophyll, chloroplast, thylakoids, stomatal and cuticular transpiration, water relations, Nicotiana tabacum
Abstrakt: Abstract Expression of the gene 4 for cytokinin synthesis in two clones of transgenic tobacco plants resulted in slightly higher (ca. 10 - 20 %) levels of endogenous cytokinins - zeatin, zeatin riboside and isopentenyladenosine. This was associated with changes in photosynthetic processes on chloroplast and leaf level. In comparison with nontransformed plantlets a higher degree of gra~a stacking was found in both clones of transgenic plants which indicated a higher proportion of photosystem 2 lightharvesting complex in thylakoids. This was supported by a decreased chlorophyll a/b ratio in the separated grana fraction. The rate of leaf net photosynthetic rate (measured as CO 2 uptake) was ca. 25 % higher in both clones than in nontransformed plants. Also the rates of dark and light respiration, and CO 2 compensation concentration were higher in transgenic plants. On the other hand, parameters of water relations (water, osmotic and pressure potentials, stomatal and cuticular transpiration rates) were not significantly affected in transgenic tobacco plants.
DOI: 10.1007/BF02928516
Autoři z ÚEB: Jana Pospíšilová
BIOLOGIA PLANTARUM 35: 393-399, 1993
Klíčová slova: chlorophyll, chloroplast, thylakoids, stomatal and cuticular transpiration, water relations, Nicotiana tabacum
Abstrakt: Abstract Expression of the gene 4 for cytokinin synthesis in two clones of transgenic tobacco plants resulted in slightly higher (ca. 10 - 20 %) levels of endogenous cytokinins - zeatin, zeatin riboside and isopentenyladenosine. This was associated with changes in photosynthetic processes on chloroplast and leaf level. In comparison with nontransformed plantlets a higher degree of gra~a stacking was found in both clones of transgenic plants which indicated a higher proportion of photosystem 2 lightharvesting complex in thylakoids. This was supported by a decreased chlorophyll a/b ratio in the separated grana fraction. The rate of leaf net photosynthetic rate (measured as CO 2 uptake) was ca. 25 % higher in both clones than in nontransformed plants. Also the rates of dark and light respiration, and CO 2 compensation concentration were higher in transgenic plants. On the other hand, parameters of water relations (water, osmotic and pressure potentials, stomatal and cuticular transpiration rates) were not significantly affected in transgenic tobacco plants.
DOI: 10.1007/BF02928516