Shade-induced ROS/NO reinforce COP1-mediated diffuse cell growth.

Canopy shade enhances the activity of PHYTOCHROME INTERACTING FACTORs (PIFs) to boost auxin synthesis in the cotyledons. Auxin, together with local PIFs and their positive regulator CONSTITUTIVELY PHOTOMORPHOGENIC 1 (COP1), promotes hypocotyl growth to facilitate access to light. Whether shade alters the cellular redox status thereby affecting growth responses, remains unexplored. Here, we show that, under shade, high auxin levels increased reactive oxygen species and nitric oxide accumulation in the hypocotyl of Arabidopsis. This nitroxidative environment favored the promotion of hypocotyl growth by COP1 under shade. We demonstrate that COP1 is S-nitrosylated, particularly under shade. Impairing this redox regulation enhanced COP1 degradation by the proteasome and diminished the capacity of COP1 to interact with target proteins and to promote hypocotyl growth. Disabling this regulation also generated transversal asymmetries in hypocotyl growth, indicating poor coordination among different cells, which resulted in random hypocotyl bending and predictably low ability to compete with neighbors. These findings highlight the significance of redox signaling in the control of diffuse growth during shade avoidance.

LED therapy modulates M1/M2 macrophage phenotypes and mitigates dystrophic features in treadmill-trained mdx mice.

The mdx mouse phenotype, aggravated by chronic exercise on a treadmill, makes this murine model more reliable for the study of Duchenne muscular dystrophy (DMD) and allows the efficacy of therapeutic interventions to be evaluated. This study aims to investigate the effects of photobiomodulation by light-emitting diode (LED) therapy on functional, biochemical and morphological parameters in treadmill-trained adult mdx animals. Mdx mice were trained for 30 min of treadmill running at a speed of 12 m/min, twice a week for 4 weeks. The LED therapy (850 nm) was applied twice a week to the quadriceps muscle throughout the treadmill running period. LED therapy improved behavioral activity (open field) and muscle function (grip strength and four limb hanging test). Functional benefits correlated with reduced muscle damage; a decrease in the inflammatory process; modulation of the regenerative muscular process and calcium signalling pathways; and a decrease in oxidative stress markers. The striking finding of this work is that LED therapy leads to a shift from the M1 to M2 macrophage phenotype in the treadmill-trained mdx mice, enhancing tissue repair and mitigating the dystrophic features. Our data also imply that the beneficial effects of LED therapy in the dystrophic muscle correlate with the interplay between calcium, oxidative stress and inflammation signalling pathways. Together, these results suggest that photobiomodulation could be a potential adjuvant therapy for dystrophinopathies.

Effects of LED lights and cytokinin on the phytotreatment of simulated swine wastewater by Azolla spp.: Pollutant removal and biomass valorization.

Phytoremediation is an eco-friendly and affordable option for tackling wastewater pollutants. The study focused on how light-emitting diodes (LED) light exposure, measured by intensity and duration (photoperiod), along with cytokinin, impacts Azolla microphylla's simulated swine wastewater treatment performance and biomass production. Under optimal treatment conditions, high removals of COD (89.2 % to 90.8 %), N-NH4+ (72.6 % to 91.2 %), N-NO3- (84.4 % to 88.6 %), Cu (75.4 % to 86.4 %), sulfamethoxazole (77.0 % to 79.0 %), P-PO43- (54.1 % to 59.9 %) and DOC (67.4 % to 71.3 %) while Zn presented a more moderate reduction (2.0 % to 9.7 %). Biomass productivity reached up to 34.8 t ha-1 yr-1. Protein production accounted for 23 % to 27 % of dry weight, while lipids ranged from 20 % to 34 % of dry biomass. Carbohydrate content varied from 8 % to 28 % of fresh weight. Higher light intensities, with both high or low values of photoperiods, and low concentrations of cytokinin were identified as optimal conditions for removal of almost all pollutants. However, pollutant removal was impacted differently by LED light and cytokinin concentration. In treatment conditions with the shortest photoperiods (8 h), the lowest residual Cu and Zn concentrations, whereas with longer photoperiods (24 h), the lowest residual concentrations of N-NH4+ and P-PO43- concentrations were recorded. On the other hand, SMX was the only parameter in which cytokinin had a clear influence on its removal, with the lowest residual concentration observed under 8-hour photoperiods combined with the lowest tested cytokinin concentrations (0.3 mg L-1). For residual COD and N-NO3-, no discernible pattern was evident for any of the analyzed factors. Therefore, the study demonstrates the potential for treating simulated swine wastewater using Azolla microphylla, aligned with its ability to produce biomass rich in high-value compounds.

Ambient light spectrum affects larval Mexican jumping bean moth (Cydia saltitans) behavior despite light obstruction from host seed.

Spectral differences in ambient light can affect animal behavior and convey crucial information about an individual's environment. The ability to perceive and respond to differences in ambient light varies widely by taxa and is shaped by a species' ecology. Mexican jumping bean moths, Cydia saltitans, spend their entire larval period encased in fallen host seeds and contend with potentially lethal environmental temperatures when host seeds are in direct sunlight. We investigate if and how C. saltitans larvae in host seeds respond to lighting conditions associated with these thermal risks. In a temperature-controlled experiment, we identified that larvae demonstrated distinct behavioral ("jumping") responses corresponding to four lighting treatments (white, red, green, and purple), despite extremely minimal light penetration through host seed walls. Red light induced the greatest larval activity (measured by probability of movement and by displacement from origin), suggesting that larvae have mechanisms to perceive low levels of red light and/or to detect subtle increases in heat produced by red/near infrared-biased light spectra, possibly providing them with an early-warning mechanism against thermal stress. Our findings highlight the interplay of environmental lighting, behavior, and potential thermosensory adaptations in a species with a visually constrained environment.

Increased color preference through the introduction of luminance noise in chromatic stimuli.

Humans exhibit consistent color preferences that are often described as a curvilinear pattern across hues. The recent literature posits that color preference is linked to the preference for objects or other entities associated with those colors. However, many studies examine this preference using isoluminant colors, which don't reflect the natural viewing experience typically influenced by different light intensities. The inclusion of random luminance levels (luminance noise) in chromatic stimuli may provide an initial step towards assessing color preference as it is presented in the real world. Employing mosaic stimuli, this study aimed to evaluate the influence of luminance noise on human color preference. Thirty normal trichromats engaged in a two-alternative forced-choice paradigm, indicating their color preferences between presented pairs. The chromatic stimuli included saturated versions of 8 standard hues, presented in mosaics with varying diameters under different luminance noise conditions. Results indicated that the inclusion of luminance noise increased color preference across all hues, specifically under the high luminance noise range, while the curvilinear pattern remained unchanged. Finally, women exhibit a greater sensitivity to the presence of luminance noise than men, potentially due to differences between men and women in aesthetic evaluation strategies.

Divergent patterns of locomotor activity in cave isopods (Oniscidea: Styloniscidae) in Neotropics.

In cave environments, stable conditions devoid of light-dark cycles and temperature fluctuations sustain circadian clock mechanisms across various species. However, species adapted to these conditions may exhibit disruption of circadian rhythm in locomotor activity. This study examines potential rhythm loss due to convergent evolution in five semi-aquatic troglobitic isopod species (Crustacea: Styloniscidae), focusing on its impact on locomotor activity. The hypothesis posits that these species display aperiodic locomotor activity patterns. Isopods were subjected to three treatments: constant red light (DD), constant light (LL), and light-dark cycles (LD 12:12), totaling 1656 h. Circadian rhythm analysis employed the Sokolove and Bushell periodogram chi-square test, Hurst coefficient calculation, intermediate stability (IS), and activity differences for each species. Predominantly, all species exhibited an infradian rhythm under DD and LL. There was synchronization of the locomotor rhythm in LD, likely as a result of masking. Three species displayed diurnal activity, while two exhibited nocturnal activity. The Hurst coefficient indicated rhythmic persistence, with LD showing higher variability. LD conditions demonstrated higher IS values, suggesting synchronized rhythms across species. Significant individual variations were observed within species across the three conditions. Contrary to the hypothesis, all species exhibited synchronization under light-dark conditions. Analyzing circadian activity provides insights into organism adaptation to non-cyclical environments, emphasizing the importance of exploring underlying mechanisms.

Effects of light quality and intensity on phycobiliprotein productivity in two Leptolyngbya strains isolated from southern Bahia's Atlantic Forest.

Cyanobacterial phycocyanin and phycoerythrin are gaining commercial interest due to their nutrition and healthcare values. This research analyzed the biomass accumulation and pigment production of two strains of Leptolyngbya under different combinations of light colors and intensities. The results showed that while Leptolyngbya sp.4 B1 (B1) produced all phycobiliproteins, Leptolyngbya sp.5 F2 (F2) only had phycocyanin and allophycocyanin. Both the color of the light and its light intensity affect the biomass accumulation and phycoerythrin concentration in strain B1. Although white light at medium intensity (50 µmol m-2 s-1) causes greater biomass accumulation (1.66 ± 0.13 gDW L-1), low-intensity (25 µmol m-2 s-1) green light induces lower biomass accumulation with twice the pigment content (87.70 ± 2.46 mg gDW -1), culminating in 71% greater productivity. In contrast, for the F2 strain, light intensity positively influenced biomass and pigment accumulation, being observed 2.25 ± 0.10 gDW L-1 under white light at 100 µmol m-2 s-1 and higher phycocyanin concentration (138.38 ± 3.46 mg gDW -1) under red light at 100 µmol m-2 s-1. These findings provide insights into optimizing the growth conditions by altering the intensity and wavelength of light for future production of phycocyanin and phycoerythrin from local cyanobacteria.

Light regulates widespread plant alternative polyadenylation through the chloroplast.

Transcription of eukaryotic protein-coding genes generates immature mRNAs that are subjected to a series of processing events, including capping, splicing, cleavage, and polyadenylation (CPA), and chemical modifications of bases. Alternative polyadenylation (APA) greatly contributes to mRNA diversity in the cell. By determining the length of the 3' untranslated region, APA generates transcripts with different regulatory elements, such as miRNA and RBP binding sites, which can influence mRNA stability, turnover, and translation. In the model plant Arabidopsis thaliana, APA is involved in the control of seed dormancy and flowering. In view of the physiological importance of APA in plants, we decided to investigate the effects of light/dark conditions and compare the underlying mechanisms to those elucidated for alternative splicing (AS). We found that light controls APA in approximately 30% of Arabidopsis genes. Similar to AS, the effect of light on APA requires functional chloroplasts, is not affected in mutants of the phytochrome and cryptochrome photoreceptor pathways, and is observed in roots only when the communication with the photosynthetic tissues is not interrupted. Furthermore, mitochondrial and TOR kinase activities are necessary for the effect of light. However, unlike AS, coupling with transcriptional elongation does not seem to be involved since light-dependent APA regulation is neither abolished in mutants of the TFIIS transcript elongation factor nor universally affected by chromatin relaxation caused by histone deacetylase inhibition. Instead, regulation seems to correlate with changes in the abundance of constitutive CPA factors, also mediated by the chloroplast.

How does the life cycle of Clinodiplosis profusa (Cecidomyiidae) adjust to phenological variations of the host plant Eugenia uniflora (Myrtaceae) in sun and shade?

Galls are plant neoformations induced by specialized parasites. Since gall inducers rely on reactive plant sites for gall development, variations in abiotic factors that affect plant phenology are expected to impact the life cycle of gall inducers. To test the hypothesis that different light conditions affect both host plant and gall inducer life cycles, we studied the system Eugenia uniflora (Myrtaceae) - Clinodiplosis profusa (Cecidomyiidae), comparing plants occurring in sunny and shaded environments. We mapped phenological differences among individuals of E. uniflora occurring in the two environments and related them to the influence of luminosity on the life cycle of the gall inducer. Shade plants showed lower intensity of leaf sprouting throughout the year compared to sun-exposed plants, especially during the rainy season. Young and mature galls are synchronized with the peak of leaf sprouting at the beginning of the rainy season, lasting longer in sun-exposed plants - approximately two months longer compared to shade plants. The greater light intensity positively impacts the formation and growth of leaves and galls, with an extended period available for their induction and growth. Thus, light is an important factor for the development of gallers, considering that variations in luminosity influenced not only the phenology of the host plant, but also determined the life cycle of gall inducers. Furthermore, changes in plant-environment interactions are expected to affect the life cycle and richness of other host plant-gall inducer systems.

The synergistic effect of photodynamic and sonodynamic inactivation against Candida albicans biofilm.

Candida albicans biofilm can cause diseases that are resistant to conventional antifungal agents. Photodynamic (PDI), sonodynamic (SDI), and sonophotodynamic (SPDI) inactivation have arisen as promising antimicrobial strategies. This study evaluated these treatments mediated by curcumin against C. albicans biofilms. For this, C. albicans biofilms were submitted to PDI, SDI, or SPDI with different light and ultrasound doses, then, the viability assay was performed to measure the effectiveness. Finally, a mathematical model was suggested to fit acquired experimental data and understand the synergistic effect of light and ultrasound in different conditions. The results showed that SPDI, PDI, and SDI reduced the viability in 6 ± 1; 1 ± 1; and 2 ± 1 log, respectively, using light at 60 J/cm2, ultrasound at 3 W/cm2, and 80 µM of curcumin. The viability reduction was proportional to the ultrasound and light doses delivered. These results encourage the use of SPDI for the control of microbial biofilm.

Influence of Luminosity on the Precision and Accuracy of Intraoral Scanning: A Comparative in vitro Study.

OBJECTIVES: This in vitro study focused on verifying the influence of different ambient light conditions on the accuracy and precision of models obtained from digital scans. METHODOLOGY: To measure the tested illuminances: chair light/reflector; room light, and natural light at the time of scanning, a luxmeter was used. From the STL file, nine experimental groups were formed. RESULTS: Of the nine specific combinations between the three IOS and the three types of lighting, it was verified that for all of them, as well as the ICC, the accuracy was also excellent, in which the measured values were not significantly influenced by the IOS brand (p = 0.994) nor by the type of lighting (p = 0.996). For precision data, GLM indicated a statistically significant interaction between IOS and lighting type. Under LS, accuracy was significantly higher with 3Shape® than with CS 3600 CareStream®, which had significantly higher accuracy than Virtuo Vivo™ Straumann®. CONCLUSIONS: The models obtained with the three IOS evaluated exhibited excellent accuracy under the different illuminance tested and the 3Shape® under the three illuminance conditions was the device that presented the best precision, specifically when using LC and LS.

Bright light increases blood pressure and rate-pressure product after a single session of aerobic exercise in men.

This study aimed to test whether bright light (BL) exposure attenuates the reduction in blood pressure (BP) postexercise compared to dim light (DL). Twenty healthy men (27 ± 5 years) randomly underwent two experimental sessions: one under BL (5000 lux) and another under dim light (DL <8lux). In each session, subjects executed a bout of aerobic exercise (cycle ergometer, 30 min, moderate intensity). BP (oscillometric) and heart rate (HR monitor) were measured, and rate-pressure-product (RPP) was calculated. Additionally, a 24-h ambulatory blood pressure monitoring (ABPM) was conducted after the sessions. Systolic BP decreased while HR increased significantly and similarly after the exercise in both sessions. Additionally, systolic BP levels were higher in BL than DL throughout the experimental session (Psession = 0.04). Diastolic (Pinteraction = 0.02) and mean (Pinteraction = 0.03) BPs decreased after exercise in DL (at 30 min), and increased in BL (at 60 and 90 min). RPP increased in both sessions postexercise, but with a main effect revealing higher levels throughout the experimental session in BL than DL (Psession = 0.04) and during the first 3 h of ABPM (p = 0.05). In healthy men, BL exposure increased systolic BP and cardiac work, and abolished the postexercise decreases of diastolic and mean BPs.

The light intensity in the cultivation environment and the impact of glyphosate on plants of the Urochloa genus.

The variation in light within the environment triggers morphophysiological changes in plants and can lead to distinct responses in sun-exposed or shaded plants to glyphosate. The response of Urochloa genotypes subjected to desiccation with 2160, 1622.4, 1080, 524.4, 273.6, and 0.0 g ha-1 of glyphosate was evaluated in full sun and shade conditions. Cayana grass, mulato II grass, and sabiá grass - hybrids recently launched on the market, in addition to palisade grass and congo grass were evaluated. Under full sun, we achieved control of congo grass using 1080 g ha-1 of glyphosate, while the other grasses required 2160 g ha-1. In the low-light environment, sabiá grass was effectively controlled with 524.4 g ha-1 of glyphosate, but the other grasses needed 273.6 g ha-1. In shading, compared to full sun, the savings with glyphosate were 75 and 76% for the control of congo grass and sabiá grass, respectively, and 87% for palisade grass, mulato II grass and cayana grass. Increasing glyphosate doses leads to a decline in the quantum efficiency of photosystem II and in the electron transport rate, especially in the shade. Urochloa genotypes are more sensitive to glyphosate in the shade, which must be considered when determining the herbicide dose.

Cattleya walkeriana Gardner (Orchidaceae) propagation: culture medium, sealing system and irradiance.

This study aimed to evaluate the influence of culture media, irradiance, and sealing system on the in vitro and ex vitro growth of Cattleya walkeriana Gardner. We used MS medium as culture medium, supplemented with 30 g L-1 of sucrose and solidified with 7.0 g L-1 of bacteriological agar. This medium served as a control, while for the other treatments we supplemented the media as follows: 2) MS with 150 g L-1 of banana pulp = P150; 3) MS with 300 g L-1 of banana pulp = P300; 4) MS with 150 g L-1 of banana peel = PE150; and 5) MS with 300 g L-1 of banana peel = PE300. The irradiances were provided by 3000K LED lamps: 86 µmol m-2 s-1 (Irradiance-1) and 128 µmol m-2 s-1 (Irradiance-2) and the conventional sealing (CSS) and sealing systems that allow gas exchange (GESS). After 120 (in vitro) and 180 days (ex vitro) of cultivation, we evaluated them for pseudobulb (PN), leaf (LN) and root number (RN), plant height (PH), pseudobulb diameter (PD), longest leaf (LL) and root length (RL), fresh mass (TFM) and survival (%SURV). There was a significant interaction for all the variables analyzed. The CM x SS double interaction was significant for PH, LL, and RL. The CM x I x SS interaction was significant for PN, LN, RN, PD, TFM, and %SURV traits of C. walkeriana grown in vitro. There was a significant interaction between CM x I x SS for all C. walkeriana traits evaluated in ex vitro culture. Using the medium with up to 150 g L-1 of banana pulp combined with Irradiance-2 and CSS provided the highest values for in vitro plant growth. However, prior cultivation in MS medium, Irradiance-1, and CSS provided the greatest survival and establishment of this species plants in ex vitro culture.

Complete photodynamic inactivation of Pseudomonas aeruginosa biofilm with use of potassium iodide and its comparison with enzymatic pretreatment.

Pseudomonas aeruginosa, a gram-negative bacterium, accounts for 7% of all hospital-acquired infections. Despite advances in medicine and antibiotic therapy, P. aeruginosa infection still results in high mortality rates of up to 62% in certain patient groups. This bacteria is also known to form biofilms, that are 10 to 1000 times more resistant to antibiotics compared to their free-floating counterparts. Photodynamic Inactivation (PDI) has been proved to be an effective antimicrobial technique for microbial control. This method involves the incubation of the pathogen with a photosensitizer (PS), then, a light at appropriated wavelength is applied, leading to the production of reactive oxygen species that are toxic to the microbial cells. Studies have focused on strategies to enhance the PDI efficacy, such as a pre-treatment with enzymes to degrade the biofilm matrix and/or an addition of inorganic salts to the PS. The aim of the present study is to evaluate the effectiveness of PDI against P. aeruginosa biofilm in association with the application of the enzymes prior to PDI (enzymatic pre-treatment) or the addition of potassium iodide (KI) to the photosensitizer solution, to increase the inactivation effectiveness of the treatment. First, a range of enzymes and PSs were tested, and the best protocols for combined treatments were selected. The results showed that the use of enzymes as a pre-treatment was effective to reduce the total biomass, however, when associated with PDI, mild bacterial reductions were obtained. Then, the use of KI in association with the PS was evaluated and the results showed that, PDI mediated by methylene blue (MB) in the presence of KI was able to completely eradicate the biofilm. However, when the PDI was performed with curcumin and KI, no additive reduction was observed. In conclusion, out of all strategies evaluated in the present study, the most promising strategy to improve PDI against P. aeruginosa biofilm was the use of KI in association with MB, resulting in eradication with 108 log bacterial inactivation.

Laser Ablation for the Synthesis of Cu/Cu2O/CuO and Its Development as Photocatalytic Material for Escherichia coli Detoxification.

Advanced Oxidation Processes (AOPs) offer promising methods for disinfection by generating radical species like hydroxyl radicals, superoxide anion radicals, and hydroxy peroxyl, which can induce oxidative stress and deactivate bacterial cells. Photocatalysis, a subset of AOPs, activates a semiconductor using specific electromagnetic wavelengths. A novel material, Cu/Cu2O/CuO nanoparticles (NPs), was synthesized via a laser ablation protocol (using a 1064 nm wavelength laser with water as a solvent, with energy ranges of 25, 50, and 80 mJ for 10 min). The target was sintered from 100 °C to 800 °C at rates of 1.6, 1.1, and 1 °C/min. The composite phases of Cu, CuO, and Cu2O showed enhanced photocatalytic activity under visible-light excitation at 368 nm. The size of Cu/Cu2O/CuO NPs facilitates penetration into microorganisms, thereby improving the disinfection effect. This study contributes to synthesizing mixed copper oxides and exploring their activation as photocatalysts for cleaner surfaces. The electronic and electrochemical properties have potential applications in other fields, such as capacitor materials. The laser ablation method allowed for modification of the band gap absorption and enhancement of the catalytic properties in Cu/Cu2O/CuO NPs compared to precursors. The disinfection of E. coli with Cu/Cu2O/CuO systems serves as a case study demonstrating the methodology's versatility for various applications, including disinfection against different microorganisms, both Gram-positive and Gram-negative.

The Collapsible Light Trap: a portable Pennsylvania Light Trap for collecting aquatic insects.

A Collapsible Light Trap (CLT) for collecting insects, particularly aquatic insects, is described here. CLT is a modified Pennsylvania Light Trap with the advantage of being collapsible and lightweight to be carried in a small backpack and very easy to set up in the field. CLT is equipped with LED light strip wrapped around a PVC tube and can be connected to a regular 12 V / 7 Ah battery, running for more than 48 uninterrupted hours. Complete CLT weighs 0.8-1.0 kg, depending on the metal used, and the battery weighs around 2 kg, being easily transportable to more remote collecting areas. Over the years, CLTs have been used for collecting and describing the diversity of aquatic insects from Brazil, particularly caddisflies. Depending on the locality, only one trap for one night can collect over a thousand insect specimens and more than 200 individuals of caddisflies.

The role of light emitting diode in wound healing: A systematic review of experimental studies.

Wounds represent a growing global issue demanding increased attention. To expedite wound healing, technologies are under development, and light emitting diode (LED) devices of varying wavelengths are being explored for their stimulating influence on the healing process. This article presents a systematic literature review aiming to compile, organize, and analyze the impacts of LED devices on wound healing. This review is registered on the PROSPERO platform [CRD42023403870]. Two blinded authors conducted searches in the Pubmed, Web of Science, Scopus, Embase, and ScienceDirect databases. In vitro and in vivo experimental studies assessing LED utilization in the wound healing process were included. The search yielded 1010 studies, of which 27 were included in the review. It was identified that LED stimulates different healing pathways, promoting enhanced cell proliferation and migration, angiogenesis stimulation, increased collagen deposition, and modulation of the inflammatory response. Thus, it can be concluded that the LED stimulates cellular and molecular processes contingent on the utilized parameters. The effects depend on the standards used. Cell migration and proliferation were better influenced by green and red LED. The extracellular matrix components and angiogenesis were regulated by all wavelengths and the modulation of inflammation was mediated by green, red, and infrared LEDs.

Unravelling the impact of light, temperature and nutrient dynamics on duckweed growth: A meta-analysis study.

Nature-based solutions have been proven in recent decades as a reliable and cost-effective technology for the treatment of wastewaters. Different plant species have been studied for this purpose, but particular attention has been given to duckweeds, the smallest flowering plant in the world. Duckweed-based systems for simultaneous wastewater treatment and nutrient recovery have the potential to provide sustainable and cost-effective solutions to reduce water pollution and increase nutrient efficiency at catchment level. However, despite being considered a seemingly simple technology, the performance of wastewater treatment systems using duckweed depends on environmental and operational conditions not very well understood. For that reason, careful consideration must be given to such environmental factors controlling duckweed biomass growth but the evidence in published literature is scare and dispersed. This study employs a systematic review approach to conduct a meta-analysis of the effect of environmental conditions on duckweed growth by means of standardised IQ-scores. The results suggest that duckweed biomass growth rates reach a maximum within specific ranges for temperature (11.4-32.3 °C), daily light integral (DLI) (5-20 mol m-2), and nitrogen (>5 mg N L-1) and phosphorus (>1 mg P L-1) concentrations; DLI was found to be a better parameter to assess the overall effect of light (photoperiod and intensity) on duckweed growth and that the effect of nitrogen and phosphorus supply should consider the nitrogen species available for plant growth and its ratio to phosphorus concentrations (recommended N:P ratio = 15:1). By establishing the optimal range of culture conditions for duckweed, this study provides important insights for optimizing engineered wastewater treatment systems that rely on duckweed for nutrient control and recovery, which is primarily mediated by duckweed growth.