Sa. Ushakova et al., PHOTOSYNTHESIS AND RESPIRATION IN PLANTS GROWN UNDER RED AND WHITE-LIGHT, Russian journal of plant physiology, 44(3), 1997, pp. 317-321
Tomato (Lycopersicon esculentum Mill), sunflower (Helianthus annuus L.
), and cucumber (Cucumis sativus L.) plants were grown under red or wh
ite light at a radiance of 115 W/m(2) under controlled conditions. The
red spectra were characterized by either two well-distinguished spect
ral lines (RL1) or only one (RL2). Apparent photosynthesis (P-a), gros
s photosynthesis (P-g), dark (R-d) and Light (R-l) respiration, the co
ntent of pigments, and the biochemical composition of plants were esti
mated. Enhancing the destructive red Light influence led to a rise in
the P-a/R-l and P-a/P-g ratios and to a decrease in chlorophyll a, nit
rate, and reduced nitrogen. RL1 was more inhibitory for plants than RL
2. It is concluded that declined energy efficiency of respiration cont
ributes to the destructive effect of RL in sunflower and cucumber plan
ts. The rearrangement of metabolic processes, at which energy efficien
cy of respiration is maintained, is responsible for adaptation of toma
to plants to red Light. The obtained results allow one to outline the
ways to study the species-specific mechanisms of plant responses to pr
olonged RL action.