Photosynthesis and hydrogen energy for sustainability: harnessing the sun for a greener future

B.D. KOSSALBAYEV, G. YILMAZ, H.G. OZCAN, G. SOYKAN, S. YALCIN, S.I. ALLAKHVERDIEV

Photosynthetica 2024, 62(2):138-146 | DOI: 10.32615/ps.2024.013  

At the dawn of the 21^st century, the rapid expansion of manufacturing plants and the widespread destruction of natural habitats significantly contributed to accelerating global warming. This phenomenon has led to severe droughts, irreversible agricultural damage, and substantial challenges in securing food supplies for the burgeoning global population. The alarming surge in atmospheric carbon dioxide concentrations underscores the urgent need to embrace clean energy technologies. To date, the primary goal of mankind is to develop innovative approaches to return Earth's ecology to its pre-industrial condition, as a century ago. The special...

Using chlorophyll fluorescence parameters and antioxidant enzyme activity to assess drought tolerance of spring wheat

S.V. ОSIPOVA, А.V. RUDIKOVSKII, А.V. PERMYAKOV, Е.G. RUDIKOVSKAYA, А.V. POMORTSEV, О.V. МUZALEVSKAYA, Т.А. PSHENICHNIKOVA

Photosynthetica 2024, 62(2):147-157 | DOI: 10.32615/ps.2024.014  

The improvement of phenotyping methods is necessary for large-scale screening studies of wheat (Triticum aestivum L.) drought tolerance. The objective of our research was to find out whether it is possible to use chlorophyll (Chl) fluorescence parameters instead of biochemical indicators of drought tolerance when screening wheat. We measured shoot biomass, gas exchange, as well as biochemical and Chl fluorescence indicators in 11 wheat genotypes grown under contrasting water supplies and differing in drought tolerance. The effect of drought on the traits was evaluated using the effect of size index. We made two independent rankings: one based...

Gas exchange and time to reach maximum rate of photosynthetic rateand their relationship with whole-plant traits in sugarcane in water abundant Louisiana, USA

P.Z. ELLSWORTH, P.M. WHITE Jr., J. TODD

Photosynthetica 2024, 62(2):158-167 | DOI: 10.32615/ps.2024.015  

Variety development of sugarcane (Saccharum spp. hybrids) is necessary to continue improving sugar yields and selecting photosynthetic traits can improve sugar production through increased carbon inputs. In this study, gas exchange and whole-plant measurements were made on 55 sugarcane genotypes in Louisiana. Variation in the relationship between photosynthetic rate and stomatal conductance suggests that sugarcane exhibits variation in both photosynthetic capacity and CO₂ substrate availability. Genotypes that reached maximum photosynthetic rate (TRMPR) in the gas-exchange cuvette more quickly had greater CO₂ assimilation...

Selenite foliar application increased the accumulation of medicinal components in Paeonia ostii by promoting antioxidant capacity, reducing oxidative stress, and improving photosynthetic capacity

L.X. ZHANG, Q.S. CHANG, Y.L. HE, X.L. ZHAO, W. LIU, Q. GUO, K. CHEN, X.G. HOU

Photosynthetica 2024, 62(2):168-179 | DOI: 10.32615/ps.2024.012  

The effects of selenite (0, 15, 30, 45 mg L^-1) on physiological characteristics and medicinal components of Paeonia ostii were analyzed. The results showed that selenite application promoted the activity of superoxide dismutase and the contents of soluble sugar, proline, carotenoids, total flavonoids, and total polyphenols, and decreased the contents of reactive oxygen species, relative electrical conductivity, and malondialdehyde. In addition, selenite also increased chlorophyll content, improved electron transfer ability, PSI and PSII performance, and the coordination between PSI and PSII, which significantly improved photosynthetic...

Influence of additional far-red light on the photosynthetic and growth parameters of lettuce plants and the resistance of the photosynthetic apparatus to high irradiance

A. SHMAREV, M. VERESHAGIN, P. PASHKOVSKIY, V.D. KRESLAVSKI, S.I. ALLAKHVERDIEV

Photosynthetica 2024, 62(2):180-186 | DOI: 10.32615/ps.2024.016  

The effects of additional far-red light (FRL) on the photosynthetic and growth parameters of Lactuca sativa plants grown for 30 d and on the photosynthetic activity of the plants under high irradiance [4 h; 1,500 μmol(photon) m^-2 s^-1] were studied. The plants were grown under coloured light-emitting diodes at a ratio of red light (RL): blue light (BL): green light (GL): far-red light (FRL) = 0.7:1:0.3:0.4 or RL:BL:GL:FRL = 0.7:1:0.3:0.8 (test, T). Additional FRL led to an increase in plant biomass, height, and leaf area but to a decrease in photosynthesis and respiration rates. However, PSII activity was greater in plants...

Changes of Cd content in chloroplasts are mirrored by the activity of photosystem I, but not by photosystem II

E.A. LYSENKO, V.V. KUSNETSOV

Photosynthetica 2024, 62(2):187-203 | DOI: 10.32615/ps.2024.018  

We searched for a direct Cd action on the photosynthetic electron transport chain using induced chlorophyll fluorescence and P₇₀₀ light absorption. Young barley and maize plants were treated with Cd in concentrations of toxic (80 μM) and nearly lethal (250 μM). The maximal and relative photochemical activities of PSI, its major limitation at the donor side, and partially acceptor-side limitation of PSII changed in agreement with Cd accumulation in the corresponding chloroplasts. Acceptor-side limitation of PSII increased with a direct Cd action at 80 μM that was overcome with an indirect Cd action at 250 μM. These alterations...

Revisiting the nonregulatory, constitutive nonphotochemical quenching of the absorbed light energy in oxygenic photosynthetic organisms

G. GARAB

Photosynthetica 2024, 62(2):204-208 | DOI: 10.32615/ps.2024.022  

The present paper aims to open discussion on the information content, physical mechanism(s), and measuring protocols to determine the partitioning of the absorbed light energy in oxygenic photosynthetic organisms. Revisiting these questions is incited by recent findings discovering that PSII, in addition to its open and closed state, assumes a light-adapted charge-separated state and that chlorophyll a fluorescence induction (ChlF), besides the photochemical activity of PSII, reflects the structural dynamics of its reaction center complex. Thus, the photochemical quantum yield of PSII cannot be determined from the conventional ChlF-based protocol....

LETTER TO THE EDITOR

U. SCHREIBER

Photosynthetica 2024, 62(2):209-211 | DOI: 10.32615/ps.2024.023  

LETTER TO THE EDITOR

H.M. KALAJI

Photosynthetica 2024, 62(2):212 | DOI: 10.32615/ps.2024.024  

Chlorophyll and growth performance of biological sand-fixing materials inoculated on sandy desert surface

H.R. REN, L. TAO, J. REN, X.C. REN

Photosynthetica 2024, 62(2):213-220 | DOI: 10.32615/ps.2024.020  

Desert biocrusts play an important role in the control of desertification and artificial inoculation can promote the formation and development of biocrusts. Physiological and growth responses of biocrusts inoculated on desert surfaces were investigated to assess the effect of mixture ratio, inoculation times, and water supply under laboratory conditions. The application of biological sand-fixing material prepared by cultivated algae crust and polymeric composites in a 1:1 ratio accelerated the most accumulation of chlorophyll a in 0.55 mg kg^-1, thickness in 3.06 mm, and fresh mass in 0.69 g cm^-1, was the most beneficial...

Biochar alleviates single and combined effects of salinity and drought stress in faba bean plants

I. RAJHI, R. NEFISSI OUERTANI, N. FERCHICHI, B. KHIARI, L. EL-BASSI, H. MHADHBI

Photosynthetica 2024, 62(2):221-231 | DOI: 10.32615/ps.2024.019  

This study aimed to evaluate the impact of four biochar concentrations (0, 2, 5, and 8%) on single and interactive effects of salinity and drought stresses on the morphological, physiological, and photosynthetic parameters of faba bean plants. PCA analysis showed that plants displayed different behavior under non-stressed and stressed conditions. The most discriminating quantitative characters were related to plant biomass production and photosynthesis, especially shoot dry mass, root dry mass, plant fresh mass, internal CO₂ concentration, net CO₂ assimilation rate, and relative water content. The obtained results confirm the...