The Role of Pigments and Cryptochrome 1 in the Adaptation of Photosynthetic Apparatus to High-Intensity Blue Light.

The effects of high-intensity blue light (HIBL, 500/1000 µmol ms, 450 nm) on mutants with high pigment () and low pigment ( levels and cryptochrome 1 (cry1) deficiency on photosynthesis, chlorophylls, phenols, anthocyanins, nonenzymatic antioxidant activity, carotenoid composition, and the expression of light-dependent genes were investigated. The plants, grown under white light for 42 days, were exposed to HIBL for 72 h. The mutant quickly adapted to 500 µmol ms HIBL, exhibiting enhanced photosynthesis, increased anthocyanin and carotenoids (beta-carotene, zeaxanthin), and increased expression of key genes involved in pigment biosynthesis (, , , ) and PSII proteins along with an increase in nonenzymatic antioxidant activity.

The Adaptive Role of Carotenoids and Anthocyanins in Pigment Mutants under High Irradiance.

The effects of high-intensity light on the pigment content, photosynthetic rate, and fluorescence parameters of photosystem II in high-pigment tomato mutants ( 3005) and low-pigment mutants ( 3617) were investigated. This study also evaluated the dry weight percentage of low molecular weight antioxidant capacity, expression patterns of some photoreceptor-regulated genes, and structural aspects of leaf mesophyll cells. The 3005 mutant displayed increased levels of photosynthetic pigments and anthocyanins, whereas the 3617 mutant demonstrated a heightened content of ultraviolet-absorbing pigments.

Investigating the Physiological and Molecular Responses of Mutants to Light of Different Quality for Biotechnological Applications.

The effect of the light of different spectral compositions, white fluorescent light (WFL), red light (RL, 660 nm), blue light (BL, 450 nm), green light (GL, 525 nm), and white LED light (WL, 450 + 580 nm), on the physiological parameters of 3005 (defective for a gene) and 4012 ; 3538 ; 0279 (defective for a gene) photomorphogenetic mutants was studied. The parameters of the primary photochemical processes of photosynthesis, photosynthetic and transpiration rates, the antioxidant capacity of low-molecular weight antioxidants, the content of the total phenolic compounds, including flavonoids, and the expression of the genes involved in light signaling and biosynthesis of secondary metabolites were determined. Under BL, the 3005 mutant showed the highest nonenzymatic antioxidant activity, which occurred to a greater extent due to the increase in flavonoid content.

Independent Responses of Photosynthesis and Plant Morphology to Alterations of PIF Proteins and Light-Dependent MicroRNA Contents in Mutants Grown under Lights of Different Spectral Compositions.

The effects of the quality of light on the content of phytochrome interacting factors (PIFs) such as PIF3, PIF4 and PIF5, as well as the expression of various light-dependent microRNAs, in adult mutant plants (, , , , ) were studied. We demonstrate that under blue light, the mutant had maximal expression of most of the studied microRNAs (miR163, miR319, miR398, miR408, miR833) when the PIF4 protein in plants was reduced. This finding indicates that the PIF4 protein is involved in the downregulation of this group of microRNAs.

Effect of Phytochrome Deficiency on Photosynthesis, Light-Related Genes Expression and Flavonoid Accumulation in under Red and Blue Light.

The effect of red (RL, 660 nm) and blue (BL, 450 nm) light on mutant tomato plants was studied. The rates of photosynthesis (Pn) and transpiration, the efficiency of the primary photochemical processes of photosynthesis, the contents of flavonoids and phenolic compounds, the low-molecular-weight antioxidant capacity (Trolox equivalent antioxidant capacity (TEAC)) of leaf extracts, and the expression of light-dependent genes were evaluated. Under RL, BL, and white fluorescent light (WFL), the Pn values decreased in the order: WT > > > , except for the Pn in on BL.

Effects of Iron Oxide Nanoparticles (FeO) on Growth, Photosynthesis, Antioxidant Activity and Distribution of Mineral Elements in Wheat () Plants.

Engineered nanoparticles (NPs) are considered potential agents for agriculture as fertilizers and growth enhancers. However, their action spectrum differs strongly, depending on the type of NP, its concentrations, and plant species per se, ranging from growth stimulation to toxicity. This work aimed to investigate effects of iron oxide (FeO) NPs on growth, photosynthesis, respiration, antioxidant activity, and leaf mineral content of wheat plants.