Behind the logic. The keyword for the week is supersaturation. The primary difference in the spectral composition between sunset and sunrise is that at sunset, the light contains a higher proportion of longer wavelengths (red, orange) due to atmospheric scattering, while at sunrise, the light has a slightly higher proportion of shorter wavelengths (blue) as the sun is initially filtering through the atmosphere, making the sky appear more blueish compared to the redder hues of sunset. Key points about spectral composition at sunrise and sunset: Longer wavelengths at sunset: When the sun is low on the horizon, sunlight travels through a thicker layer of the atmosphere, causing more scattering of shorter wavelengths (blue) and allowing longer wavelengths (red, orange) to reach our eyes, resulting in vibrant sunset colors. Shorter wavelengths at sunrise: At sunrise, the light also travels through a thick atmosphere, but the scattering effect is slightly different due to the atmospheric conditions, leading to a slightly higher presence of blue light compared to sunset. 4 Hours 1000-1800ppf @ UVB peak in the afternoon, 4 hours of 700-1000ppf on either side with differing ratios of PR/PRF and Peak UVA @ both Sunrise and Sunset, nature knows best. •The level of antioxidants depends on the stress severity and duration. •The plant’s antioxidants response to light and temperature in a short- and long-term manner (acclimation). •Under severe, short stress, the levels of antioxidants tend to decrease. •Under acclimation (long-term responses) the levels of antioxidants gradually increase. Cannabis contains antioxidants like cannabinoids, flavonoids, and phenolic compounds. Δ9-tetrahydrocannabinol (THC) Has been shown to be an antioxidant and prevent hydroperoxide-induced oxidative damage. Auxins are mainly involved in plant growth at the tips of plants. Gibberellins are involved in stem elongation, as well as various other aspects of plant growth such as flowering and fruit production. abscisic acid is the hormone that acts opposite to auxins, gibberellins, and cytokinins. EXPLANATION: Abscisic acid is the plant hormone that controls the organ size and stomatal closure, and also actively responds against environmental stress or biotic stress. Plants are an integral component in the global movement of water from the soil to the atmosphere, which is referred to as the hydraulic soil–plant–air continuum. Gradients of water vapor generate strong forces for water mobilization. At 20 °C, for example, a one percent difference in water saturation between plant tissues and the air generates a water potential difference of −1.35 MPa (−13.5 bar) which drives transpiration. In essence, plants facilitate the translocation of water from the root zone, back into the air. A number of different endogenous signals have been proposed for long-distance communication of the water deficit of roots to leaves. These range from chemical to hydraulic, and electric signals. ABA was identified as a chemical being delivered in increased amounts to the shoot in the transpiration stream during drought. Electrical signals emanate from water-stressed roots or from roots after re-irrigation and have been suggested to be relayed independently of hydraulic function. How is the change in Ψw sensed within the plant? The hydraulic signal generated by water deficit causes first, a reduction of turgor and second, a moderate increase in solute concentrations because of water withdrawal from cells, and third, mechanical forces exerted at the cell wall and at the cell wall-plasma membrane interface. Pioneering work uncovered the importance of turgor loss for triggering ABA biosynthesis whereas lowering cellular osmotic potential without reducing turgor was Low-level UVA exposure increases Zeaxanthin production 2 fold. Plants have evolved several efficient protective mechanisms that make it possible for them to survive under unfavorable light and temperature conditions. These mechanisms are linked predominantly to the photosynthetic electron transport chain, the xanthophyll cycle, and the photorespiratory pathway. Under stress conditions, elevated levels of reactive oxygen species (ROS) are produced, which in addition to deleterious effects also show signaling functions. In response to enhanced ROS formation, different low-molecular antioxidants are synthesized, as well as antioxidant enzymes. Depending on the stress intensity and its duration, the content of synthesized antioxidants varies. Under severe, short light/temperature stress, the contents of low-molecular-weight antioxidants, such as ascorbate, glutathione and prenyllipids, tend to decrease, which is correlated with an extra need for ROS scavenging. Under longer exposure of plants to unfavorable light and temperature conditions, the contents of antioxidants gradually increase as a result of acclimation during long-term responses. Studies on plant antioxidant responses indicate that a crucial part of the antioxidant network operates in chloroplasts and their action shows a high level of interdependence. The antioxidant response also depends on plant stress tolerance. Under acclimation (long-term responses) the levels of antioxidants gradually increase. Ascorbic acid and Zeanathaxin are the two co-enzymes responsible for ROS and NPQ, helping the plant deal with the rigors of excess light. Too much light can be harmful and excess light energy can be dissipated as fluorescence or heat (nonphotochemical quenching, NPQ). At least part of this nonradiative energy dissipation occurs through reversible covalent modifications of the thylakoid xanthophylls and involves the reductive de-epoxidation of violaxanthin to zeaxanthin (xanthophyll cycle) that is triggered by the pH gradient produced by photosynthetic electron flow. A genetic analysis of NPQ-deficient mutants provided direct genetic evidence for the importance of zeaxanthin in NPQ and also revealed that the pigments of the xanthophyll cycle derived from β-carotene, and lutein derived from α-carotene are required both for NPQ and for protection against oxidative damage in high light. https://www.sciencedirect.com/topics/medicine-and-dentistry/xanthophyll-cycle https://www.sciencedirect.com/science/article/abs/pii/S0098847217301065?via%3Dihub