The role of light quality of photoperiodic lighting on photosynthesis, flowering and metabolic profiling in
            Ranunculus asiaticus
            L.

Light is an important cue that stimulates both plastid development and biosynthesis of carotenoids in plants. During photomorphogenesis or de-etiolation, photoreceptors are activated and molecular factors for carotenoid and chlorophyll biosynthesis are induced thereof. In fruits, light is absorbed by chloroplasts in the early stages of ripening, which allows a gradual synthesis of carotenoids in the peel and pulp with the onset of chromoplasts’ development. In roots, only a fraction of light reaches this tissue, which is not required for carotenoid synthesis, but it is essential for root development. When exposed to light, roots start greening due to chloroplast development. However, the colored taproot of carrot grown underground presents a high carotenoid accumulation together with chromoplast development, similar to citrus fruits during ripening. Interestingly, total carotenoid levels decrease in carrots roots when illuminated and develop chloroplasts, similar to normal roots exposed to light. The recent findings of the effect of light quality upon the induction of molecular factors involved in carotenoid synthesis in leaves, fruit, and roots are discussed, aiming to propose consensus mechanisms in order to contribute to the understanding of carotenoid synthesis regulation by light in plants.

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Metabolic Profile and Performance Responses of Ranunculus asiaticus L. Hybrids as Affected by Light Quality of Photoperiodic Lighting

Frontiers in Plant Science ◽

10.3389/fpls.2020.597823 ◽

2020 ◽

Vol 11 ◽

Author(s):

Petronia Carillo ◽

Emilia Dell’Aversana ◽

Giuseppe Carlo Modarelli ◽

Giovanna Marta Fusco ◽

Stefania De Pascale ◽

...

Keyword(s):

Metabolic Profiling ◽

Time Course ◽

Light Quality ◽

Red Light ◽

Day Length ◽

Light Sources ◽

Light Spectrum ◽

Vegetative Development ◽

Tuberous Roots ◽

Ranunculus Asiaticus

Ranunculus asiaticus is a quantitative long day plant grown for cut flowers and flowering potted plants production. We evaluated the influence of light spectrum of three light sources for end-of-day photoperiodic treatments, with different phytochrome photoequilibria (PPE) induced at plant level, on the metabolic profiling of two hybrids of R. asiaticus L., MBO and MDR, in plants from vernalized tuberous roots. The following treatments were compared with natural day length (NL): white fluorescence lamp (FL, PPE 0.84), light emitting diodes (LEDs) Red:Far Red light at 3:1 ratio (R:FR 3:1, PPE 0.84), and LEDs Red:Far Red light at 1:3 ratio (R:FR 1:3, PPE 0.63). Measurements were carried out to evaluate the time course of carbohydrate, amino acid, and protein levels throughout the growing cycle in tuberous roots and leaves, in relation to the different plant stages (pre-planting, vegetative phase, and flowering). The study of metabolic profiling suggested that the differences between the tuberous root reserves of the two R. asiaticus hybrids could be responsible for the capacity of MBO to exert an early flowering. In particular, the proton-consuming synthesis during the pre-planting of two amino acids, alanine and γ-aminobutyric acid (GABA), is able to buffer the cytoplasmic acidosis and pH altered by the vernalization process, and GABA itself can efficiently scavenge reactive oxygen species. This fast response to the stress caused by vernalization allows MBO plants to accelerate the process of vegetative development and flowering. Some other changes in metabolites profile were certainly related to the different responses to day length and photoperiodic light quality in the two hybrids, such as dose exerted by low R:FR lighting in both MBO and MDR. However, most of the responses are under a strict genetic control.

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THE ROLE OF LIGHT QUALITY IN THE FORCING OF TULIPS AND HYACINTHS AND IN THE PROPAGATION OF HYACINTH BULBS

Acta Horticulturae ◽

10.17660/actahortic.1992.305.16 ◽

1992 ◽

pp. 111-112

Author(s):

H. Gude ◽

M. Dijkema

Keyword(s):

Light Quality ◽

Role Of Light

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Transcriptomic and metabolic analysis uncovers the role of light quality in carotenoid accumulation of grapefruit during ripening

10.21203/rs.3.rs-825511/v1 ◽

2021 ◽

Author(s):

Liulian Huang ◽

Linping Hu ◽

Wenbin Kong ◽

Can Yang ◽

Wanpeng Xi

Keyword(s):

Red Light ◽

Carotenoid Content ◽

Citrus Fruits ◽

Carotenoid Metabolism ◽

Total Carotenoid Content ◽

Carotenogenic Genes ◽

Induced Changes ◽

Role Of Light

Abstract Light, a crucial environmental signal, is involved in the regulation of secondary metabolites. To understand the mechanism by which light influences carotenoid metabolism, grapefruits were bagged with four types of light-transmitting bags that altered the transmission of solar light. We showed that light-transmitting bagging induced changes in carotenoid metabolism during fruit ripening. Compared with natural light, red light (RL)-transmittance treatments significantly increased the total carotenoid content by 142%. Based on weighted gene co-expression network analysis (WGCNA), ‘red’, ‘darkred’, ‘yellow’, ‘brown’ and ‘midnightblue’ modules were remarkably associated with carotenoid metabolism under different light treatment. Transcriptome analysis identified the transcription factors (TFs) bHLH74/91/122, NAC56/78/90/100, MYB/MYB308, WRKY7/55, MADS29/AGL61, ERF043/118 as being involved in the regulation of carotenoid metabolism in response to RL. Under RL treatment, these TFs regulated the accumulation of carotenoids by directly modulating the expression of carotenogenic genes, including PSY, Z-ISO2, ZDS6, LCYB, LCYE, CHYB, CCD1-1/1-3, CCD4-2 and NCED2/3. Based on these results, a network of the regulation of carotenoid metabolism by light in citrus fruits was preliminarily proposed. These results showed that RL treatments have great potential to improve coloration and nutritional quality of citrus fruits.

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Cognitive Health Counseling 40+

Zeitschrift für Gesundheitspsychologie ◽

10.1026/0943-8149/a000085 ◽

2013 ◽

Vol 21 (1) ◽

pp. 24-33 ◽

Cited By ~ 1

Author(s):

Anne Eschen ◽

Franzisca Zehnder ◽

Mike Martin

Keyword(s):

Outcome Variable ◽

Pilot Phase ◽

Subjective Memory ◽

Cognitive Health ◽

Health Counseling ◽

Agents Of Change ◽

Main Outcome Variable ◽

Further Development

This article introduces Cognitive Health Counseling 40+ (CH.CO40+), an individualized intervention that is conceptually based on the orchestration model of quality-of-life management ( Martin & Kliegel, 2010 ) and aims at improving satisfaction with cognitive health in adults aged 40 years and older. We describe the theoretically deduced characteristics of CH.CO40+, its target group, its multifactorial nature, its individualization, the application of subjective and objective measures, the role of participants as agents of change, and the rationale for choosing participants’ satisfaction with their cognitive health as main outcome variable. A pilot phase with 15 middle-aged and six older adults suggests that CH.CO40+ attracts, and may be particularly suitable for, subjective memory complainers. Implications of the pilot data for the further development of the intervention are discussed.

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