[Effect of the exogenous glucose on photosynthesis of the diatom Thalassiosira weissflogii depending on nitrate supply and light].
The rate of photosynthetic carbon fixation (P) in the diatom Thalassiosira weissflogii cultivated in the presence of exogenous glucose in the medium (0-10.56 micrograms C/l) at different levels of illumination (25, 50, and 100 microE/m2 s) was studied as a function of nitrate nitrogen supply. In the diatoms limited in nitrogen and assimilating exogenous glucose, P was found to decrease or increase depending on light intensity, glucose concentration, and the duration of exposure. In the diatoms assimilating both nitrate nitrogen and glucose, compared to those supplied with nitrates alone, P was higher at medium and high light intensities and lower at a low light intensity. The interrelation of the processes of carbon and nitrogen metabolism in mixotrophic algae and the ecological role of glucose consumption by phytoplankton are discussed.
Radchenko
I G
IG
Biological Faculty, Moscow State University, Vorob'evy gory, Moscow, 119899 Russia. Radchenk@2.hydro.bio.msu.ru
Il'iash
L V
LV
Fedorov
V D
VD
D002244:Carbon / Q000378:metabolism; D003470:Culture Media; D017377:Diatoms / Q000187:drug effects / Q000502:physiology*; D005947:Glucose / Q000494:pharmacology*; D008027:Light; D009566:Nitrates / Q000378:metabolism*; D009584:Nitrogen / Q000378:metabolism; D010788:Photosynthesis / Q000187:drug effects / Q000502:physiology*
D003470:Culture Media; D009566:Nitrates; D002244:Carbon; D005947:Glucose; D009584:Nitrogen