Interrelationships Between Nitrogen Supply and Photosynthetic Parameters in Vicia faba L.

Abstract

We determined for Vicia faba L the influence of nitrogen uptake and accumulation on the values of photon saturated net photosynthetic rate (P Nmax ), quantum yield efficiency (α), intercellular CO 2 concentration (C i ), and carboxylation efficiency (C e ). As leaf nitrogen content (N L ) increased, the α converged onto a maximum asymptotic value of 0.0664±0.0049 µmol(CO 2 ) µmol(quantum) -1 . Also, as N L increased the C i value fell to an asymptotic minimum of 115.80±1.59 µmol mol -1 , and C e converged onto a maximum asymptotic value of 1.645±0.054 µmol(CO 2 ) m -2 s -1 Pa -1 and declined to zero at a N L -intercept equal to 0.596±0.096 g(N) m -2 . α fell to zero for an N L -intercept of 0.660±0.052 g(N) m -2 . As N L increased, the value of P Nmax converged onto a maximum asymptotic value of 33.400±2.563 µmol(CO 2 ) m -2 s -1 . P N fell to zero for an N L -intercept of 0.710±0.035 g(N) m -2 . Under variable daily meteorological conditions the values for N L, specific leaf area (δ L ), root mass fraction (R f ), P Nmax , and α remained constant for a given N supply. A monotonic decline in the steady-state value of R f occurred with increasing N supply. δ L increased with increasing N supply or with increasing N L .

Effects of water stress and nitrogen supply on leaf gas exchange and fluorescence parameters of Sophora davidii seedlings

“…Theoretically, P max , which determines the plant potential photosynthetic capacity, is proportional to the number of active catalytic sites in chloroplasts that are involved in the reductive assimilation of CO 2 (Jia and Gray 2003). In our study, decreased P max under water stress and increased P max at N supply were respectively associated with stomatal closure and improvement of carboxylation efficiency as discussed above, suggesting that N supply could enhance potential photosynthetic capacity under water deficit.…”

Influence of phosphorus and nitrogen on photosynthetic parameters and growth in Vicia faba L.

“…Aquadulce Claudia (Straathof Seed Group) requiring approximately 130-150 d for crop development was used. Outdoor experimental pot trials were carried out as reported in Jia and Gray (2003). Faba bean seeds were planted in 15 cm diameter (area equivalent to ---0.0177 m 2 ) pots.…”

Photosystem II photochemistry and physiological parameters of three fodder shrubs, Nitraria retusa, Atriplex halimus and Medicago arborea under salt stress

“…Some studies have shown that the decreased photosynthesis under salt stress was associated with decreased diffusion of CO 2 to chloroplasts, caused by stomata closure and/or by changes in mesophyll structure (Delfine et al 1998;Netondo et al 2004). On other hand, some works showed that the non-stomatal photosynthesis limitation could be attributed to the perturbations of biochemical processes, such as decrease in ribulose bisphosphate carboxylase/oxygenase (Rubisco) activity, decrease in ribulose-1,5-bisphosphate (Delfine et al 1998), and to the reduced carboxylation efficiency (Jea and Gray 2004). The effect of salt stress on photosynthesis is still controversial.…”