Search Results (287)

Cannabis sativa L. is a versatile plant with significant medicinal, industrial, and recreational applications. Its therapeutic potential is attributed to cannabinoids like THC and CBD, whose production is influenced by environmental factors, such as radiation, temperature, and humidity. Radiation, for instance, is essential for photosynthetic processes, acting as both a primary energy source and a regulator of plant growth and development. This review covers key factors affecting C. sativa cultivation, including photoperiod, light spectrum, cultivation methods, environmental controls, and plant growth regulators. It highlights how these elements influence flowering, biomass, and cannabinoid production across different growing systems, offering insights for optimizing both medicinal and industrial cannabis cultivation. Studies indicate that photoperiod sensitivity varies among cultivars, with some achieving optimal flowering and cannabinoid production under extended light periods rather than the traditional 12/12 h cycle. Light spectrum adjustments, especially red, far-red, and blue wavelengths, significantly impact photosynthesis, plant morphology, and secondary metabolite accumulation. Advances in LED technology allow precise spectral control, enhancing energy efficiency and cannabinoid profiles compared to conventional lighting. The photoperiod plays a vital role in the cultivation of C. sativa spp., directly impacting the plant’s developmental cycle, biomass production, and the concentration of cannabinoids and terpenes. The response to photoperiod varies among different cannabis cultivars, as demonstrated in studies comparing cultivars of diverse genetic origins. On the other hand, indoor or in vitro cultivation may serve as an excellent alternative for plant breeding programs in C. sativa, given the substantial inter-cultivar variability that hinders the fixation of desirable traits. Full article

This study aimed to determine the effects of LED applications and application periods on seedling development. To this end, four different LED applications (blue 100%, red 100%, green 100%, and full-spectrum 100% (control)) were applied to different star flower varieties (Figaro Violet shades—flower color: purple, Figaro Orange shades—flower color: orange, Figaro White shades—flower color: white, and Figaro Red shades—flower color: red) for 15 and 30 days. These applications were repeated over two years (two vegetation periods). The results revealed that the red-flowered and white-flowered varieties exhibited higher values in terms of root length, root number, stem diameter, 2nd and 4th leaf petiole length, 2nd and 4th leaf width, and leaf number under full-spectrum and red LED applications. We also observed that red LED application for 30 days is suitable for seedling height development in the Figaro Orange shades variety. Conversely, the results showed that the effects of LED application durations on root length and stem diameter did not show a statistically significant difference, while the 15-day application yielded the best results for root number. In the Figaro Red shades and Figaro White shades varieties, the use of red LED applications for 30 days yielded results similar to those of full-spectrum applications, indicating that both applications can be used for seedling cultivation. Full article

To ensure the year-round efficient production of high-quality cherry tomatoes, this study evaluated how four cherry tomato cultivars can enhance yield and quality through optimized nutrient solution and supplementary lighting. Nutrient solutions (N1 and N2) were adjusted, with EC at 1.6 dS/m (N1: nitrogen 10.7 me/L, phosphorus 2.7 me/L, potassium 5.3 me/L) during flowering stage, and 2.4 dS/m (N1: nitrogen 16 me/L, phosphorus 4 me/L, potassium 8 me/L; N2: nitrogen 10.7 me/L, phosphorus 5.4 me/L, potassium 10.8 me/L) from fruit setting to harvest. N1 used standard adjustments, while N2 was optimized by adding solely with KCl and KH₂PO₄. Lighting treatments included L1 (natural light) and L2 (supplemental red/blue light). The application of N2 effectively decreased nitrate levels while it significantly enhanced the content of soluble sugars, flavor, and overall palatability, especially fruit coloring in cherry tomatoes, irrespective of supplementary lighting conditions. However, such optimization also increased sourness or altered the sugar–acid ratio. Supplementary lighting generally promoted the accumulation of soluble sugars, sweetness, and tomato flavor, although its effects varied markedly among different fruit clusters. The combination of optimized nutrient solutions and supplementary lighting exhibited synergistic effects, improving the content of soluble sugars, vitamin C, proteins, and flavor. N1 combined with L2 achieved the highest plant yield. Among the cultivars, ‘Linglong’ showed the greatest overall quality improvement, followed by ‘Baiyu’, ‘Miying’, and ‘Moka’. In conclusion, supplementary lighting can enhance the effect of nitrogen on yield and amplify the influence of phosphorus and potassium on fruit quality improvement in cherry tomatoes. The findings of this study may serve as a theoretical basis for the development of year-round production techniques for high-quality cherry tomatoes. Full article

Calendula officinalis L. is a widely used medicinal plant whose secondary metabolism and morphology are influenced by light. This study evaluated the effects of 2 and 4 h end-of-day (EOD) red/far-red (R:FR) and green (G) light on the growth, physiology, and phytochemical profile of hydroponically grown C. officinalis under a constant red/blue light background, compared with a red/blue control without EOD treatment. Morphological, physiological (gas exchange, chlorophyll fluorescence), biochemical (chlorophyll, anthocyanin), and chemical composition (attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR) and Gas Chromatography-Mass Spectrometry (GC-MS)) were evaluated. EOD G 2 h enhanced photosynthetic pigments, anthocyanins, and biomass, while control plants showed higher phenolic content. EOD R:FR induced stem elongation but reduced pigment and metabolite accumulation. GC-MS revealed organ-specific metabolic specialization, with flowers displaying greater chemical diversity than leaves. EOD G favored sesquiterpene diversity in flowers, while EOD R:FR increased nitrogen-containing compounds and unsaturated fatty acids. Vibrational data supported these shifts, with spectral signatures of esters, phenolics, and lipid-related structures. Bioactive compounds, including α-cadinol and carboxylic acids, were identified across treatments. These findings demonstrate that EOD light modulates physiological and metabolic traits in C. officinalis, highlighting EOD G as an enhancer of biomass and phytochemical richness for pharmaceutical applications under controlled conditions. Full article

Light quality and duration profoundly influence the growth and productivity of plant species. This study investigated the effects of a blue–red LED light combination, known to induce flowering, on the physiological state and content of biologically active substances in catmint (Nepeta nuda L.) grown under controlled in vitro conditions. White light (W) was used as a control and compared with two blue–red intensities: BR (high-intensity blue–red light) and BRS (low-intensity blue–red light or “BR with shadow”). BR-treated plants showed increased leaf area, mesophyll thickness, biomass and starch content but reduced levels of plastid pigments. BR also modified the oxidative state of plants by inducing lipid peroxidation while simultaneously activating ROS scavenging mechanisms and enhancing phenolic antioxidants. Interestingly, BR decreased the accumulation of the Nepeta sp.-specific iridoid, nepetalactone. These effects appear to be regulated by the phytohormones auxin, abscisic acid and jasmonates. BRS treatment produced effects similar to the W control but led to increased plant height and reduced leaf area and thickness. Both BR and BRS regimes induced the accumulation of proteins and amino acids. We conclude that blue–red light can enhance the survival capacity of micropropagated N. nuda during subsequent soil adaptation, suggesting that similar light pre-treatment could improve plant performance under stress conditions. Full article

This study examined three innovative ‘light-converting films’ that convert green light (−23%) into red light (+8%; Red film), ultraviolet light (−80%) into blue light (+9%; Blue film), and green light (−5.7%) into red light (+4%; Pink film) but also ultraviolet light (−76%) into blue light (+5.6%; Pink film). These films were used for growing blueberry plants under cover under controlled tunnel conditions (27.3 ± 11.7 °C, 51.9 ± 21.6% RH). The use of Red film led to increases in the total plant biomass (+54.2%), and Red and Pink films enhanced the leaf thickness (+17.1% and +14.4%, respectively) as compared to the control (a transparent polyethylene film). No differences in the photosynthetic rate (P_n) were observed at the flowering stage, but a decrease (−25.9%) was observed in plants grown under the Pink film during the green fruit stage. The plants grown under Blue film boosted flower production, leading to +86.8% increase in the total yield. The Blue film improved the total phenolic content (+15.2%) in the fruit, and a +25.3% greater total antioxidant capacity was observed in fruit grown under Pink film. Freshly harvested blueberries were subjected to postharvest experiments (4 °C; in dark conditions; 90–95% RH). The results suggest the importance of Red film in enhancing plant biomass and Red and Blue films in improving fruit yield and maintaining nutraceutical postharvest quality in blueberry fruit. Full article

The green-chemical preparation of silver nanoparticles (AgNPs) offers a sustainable and environmentally friendly alternative to conventional synthesis methods, thereby representing a paradigm shift in the field of nanotechnology. The biological synthesis process, which involves the synthesis, characterization, and management of materials, as well as their further development at the nanoscale, is the most economical, environmentally friendly, and rapid synthesis process compared to physical and chemical processes. Ligustrum ovalifolium flower extract was used for the preparation of AgNPs. The synthesized AgNPs were examined by using UV–visible spectroscopy, XRD, SEM, and TEM analysis. It indicates that AgNPs were formed in good size. AgNPs were applied as a catalyst for the degradation of pollutants, such as methyl orange, Congo red, and methylene blue, which were degraded within 8–16 min. Additionally, the reduction of para-nitrophenol (PNP) to para-aminophenol (PAP) was achieved within 2 min. This work demonstrates a practical, reproducible, and efficient method for synthesizing cost-effective and stable AgNPs, which serve as active catalysts for the rapid degradation of hazardous organic dyes in an aqueous environment. Full article

To investigate whether blue-dominant spectra from end-of-day (EOD) lighting can regulate crop morphological and flowering responses, chrysanthemum (Chrysanthemum × morifolium; obligate short day), geranium (Pelargonium × hortorum; day neutral), calibrachoa (Calibrachoa × hybrida; facultative long day), and gerbera (Gerbera jamesonii; facultative short day) plants were grown under different light-emitting diode (LED) spectrum treatments from January to April 2020, in Guelph, Canada. The spectrum treatments were (1) no EOD lighting, (2) narrowband blue from LEDs (B), (3) a combination of narrowband blue, red, and far-red LEDs with a photon flux ratio of 47:3:1 (blue:red:far-red; BRFR). The B and BRFR treatments ran daily from 0.5 h to 4.5 h after dusk. Compared to the control without EOD lighting, chrysanthemum flower initiation was completely inhibited under BRFR. Flowering time was slightly delayed, but flower bud number increased under B. Side branch number, leaf area, and main stem length and diameter increased under B and BRFR. In the geranium B and BRFR did not affect flowering, but increased side branch number and length and diameter of the main stem. Both spectrum treatments promoted earlier flowering in the calibrachoa, but BRFR produced more flower buds. The calibrachoa aerial dry biomass and main stem length increased under B and BRFR. The gerbera leaf chlorophyll index and leaf thickness increased under BRFR. Both spectrum treatments increased the gerbera flower bud size, despite having little effect on flowering time. In all species, at least one of the LED treatments increased canopy size. Therefore, low levels of B or BRFR can be potentially used for EOD lighting to regulate the flowering and morphology of potted ornamentals. Full article

This paper proposes a cluster-based flight path construction method for automated drone-assisted pear pollination systems in orchard environments. The approach uses RGB-D (Red-Green-Blue-Depth) sensing through an observation drone equipped with RGB and depth cameras to detect blooming pear flowers. Flower detection is performed using a YOLO (You Only Look Once)-based object detection algorithm, and three-dimensional flower positions are estimated by integrating depth information with the drone’s positional and orientation data in the east-north-up coordinate system. To enhance pollination efficiency, the method applies the OPTICS (Ordering Points To Identify the Clustering Structure) algorithm to group detected flowers based on spatial proximity that correspond to branch-level distributions. The cluster centroids then construct a collision-free flight path, with offset vectors ensuring safe navigation and appropriate nozzle orientation for effective pollen spraying. Field experiments conducted using RTK-GNSS-based flight control confirmed the accuracy and stability of generated flight trajectories. The drone hovered in front of each flower cluster and performed uniform spraying along the planned path. The method achieved a fruit set rate of 62.1%, exceeding natural pollination at 53.6% and compared to the 61.9% of manual pollination. These results demonstrate the effectiveness and practicability of the method for real-world deployment in pear orchards. Full article

In controlled environment agriculture (CEA), supplementary lighting, particularly light-emitting diode (LED) technology, is essential for optimizing plant growth and development. Among the spectral components, blue light (400–500 nm) plays an important role in affecting plant morphogenesis, photosynthesis, and key physiological processes. However, species-specific guidelines for optimizing blue light parameters such as intensity, duration, and spectral ratios remain insufficiently developed. Furthermore, plant spectral requirements shift across developmental stages, highlighting distinct blue light management strategies for each phase. This review synthesizes existing knowledge on the impacts of blue light on morphological adaptation, photosynthetic efficiency, flowering, and secondary metabolism, with an emphasis on differential responses across diverse plant species. We emphasize the need for growth-stage-specific lighting protocols and scalable strategies applicable to commercial CEA systems. Interdisciplinary collaboration, integrating molecular biology, genomics, and horticultural engineering, is necessary to enhance understanding of blue light-driven regulatory networks, optimize photoreceptor responses, and facilitate systematic validation of adaptive lighting approaches, ultimately advancing sustainable horticulture and next-generation CEA innovations. Full article

Blue light (BL) plays a crucial role in regulating floral transition and can be precisely manipulated in controlled-environment agriculture (CEA). However, previous studies on BL-mediated flowering in CEA have produced conflicting results, likely due to species-specific responses and variations in experimental conditions (such as light spectrum and intensity) as summarized in our recent systematic review. This speculation still lacks a mechanistic explanation at the molecular level. By synthesizing recent advances in our understanding of the signaling mechanisms underlying floral transition, this review highlights how both internal signals (e.g., hormones, carbohydrates, and developmental stage) and external cues (e.g., light spectrum, temperature, nutrients, stress, and magnetic fields) are integrated into the flowering pathway mediated by BL. Key signal integration nodes have been identified, ranging from photoreceptors (e.g., cryptochromes) to downstream components such as transcription factors and central flowering regulator, FLOWERING LOCUS T (FT). This signal integration offers a potential mechanistic explanation for the previously inconsistent findings, which may arise from interspecies differences in photoreceptor composition and variation in the expression of downstream components influenced by hormonal crosstalk, environmental conditions, and developmental stage, depending on the specific context. This review provides novel molecular insights into how BL modulates floral transition through interactions with other signals. By systematically compiling and critically assessing recent research findings, we identify key research gaps and outline future directions, particularly the need for more studies in agriculturally important crops. Furthermore, this review proposes a conceptual framework for optimizing BL-based lighting strategies and exploring underexamined interaction factors in the regulation of flowering. Full article

Real-time monitoring of cotton moisture status and determination of appropriate irrigation thresholds are essential for achieving precision irrigation. Currently employed diagnostic methods based on physiological indicators, remote sensing, or soil moisture measurements typically present limitations including cumbersome procedures, high labor intensity, requirements for specialized technical expertise, and delayed results. To address these challenges, this study investigated the relationship between plant water content and leaf RGB color values (red, green, and blue color values measured using LScolor technology) during the bud, flowering, and boll development stages, with the objective of establishing a predictive model for rapid, real-time moisture status monitoring. Given that leaf position and color values (R, G, and B) of different functional leaves may influence the relationship between leaf color and plant water content, and this relationship varies across different temporal periods, a two-year experiment was conducted. In 2023, leaf color data from the top five functional leaves were measured at five time points daily throughout the irrigation cycle. In 2024, the following four irrigation treatments were established: one conventional irrigation control treatment (CK) and three irrigation treatments at 72% (T1), 70% (T2), and 68% (T3) plant water content thresholds. Results demonstrated that the following: (1) plant water content initially declined during the day and subsequently showed slight recovery, indicating cotton’s particular susceptibility to water stress between 2:30 p.m. and 7:00 p.m.; (2) plant water content continuously decreased across five measurement periods following irrigation during the bud, flowering, and boll development stages, with R and G color values of the five functional leaves showing declining trends between 2:30 p.m. and 7:00 p.m., while B color values exhibited no consistent pattern; (3) correlation analysis revealed significant positive correlations between plant water content and R and G color values of the five functional leaves during the 2:30 p.m. to 5:00 p.m. period, with highly significant correlations observed for the third and fourth leaves from the apex; (4) univariate and bivariate linear regression models were successfully established between cotton water content and R and G color values of the third and fourth leaves from the top; and (5) under 72% plant water content conditions, cotton achieved the highest yield and Irrigation Water Use Efficiency, indicating that 72% represents the optimal irrigation threshold. In conclusion, integrating leaf color–plant water content relationships with the 72% irrigation threshold enables rapid, non-destructive, large-scale diagnosis of cotton moisture status, providing a robust foundation for implementing effective precision irrigation strategies. Full article

The introduction of new ornamental species and cultivars is one of the hallmarks of innovation in global floriculture. Brunfelsia uniflora, a subshrub native to Brazil, has white, lilac, and blue flowers on the same plant, in addition to a distinctive fragrance. As it is a wild species, technologies such as large-scale clonal propagation of superior genotypes are still scarce, limiting its supply to the flower market. Therefore, a successful micropropagation protocol was developed for B. uniflora using nodal segments and shoot tips as initial explants. In the multiplication phase, the use of 6-benzylaminopurine produced the highest multiplication rates (10.3–10.9 shoots/explant) and the number of leaves in the shoots. In vitro shoot rooting using MS medium with reduced macronutrient concentrations and supplemented with IBA resulted in a 91.7% rooting rate. The greatest difficulty in micropropagating this species was the high percentage of shoots that developed calli. The highest percentage of callus formation occurred with the addition of auxins at high concentrations (1.0 and 1.5 mg L⁻¹). Even so, the shoots and plantlets were acclimatized, demonstrating the effectiveness of this technique for the production of B. uniflora plantlets. Full article

Dendrobium officinale holds significant value as a traditional medicinal plant, with its stems serving as the primary medicinal component and polysaccharides acting as the key active ingredients. To systematically analyze the biosynthetic pathways of polysaccharides and identify key genes involved in polysaccharide synthesis, this research assessed the water-soluble polysaccharide content and conducted transcriptome sequencing on stem tissues of D. officinale at different developmental stages. The findings revealed that the water-soluble polysaccharide level in D. officinale stems exhibited an increasing trend followed by a decrease, reaching its peak before flowering. Transcriptome analysis identified 5764, 6408, 4477, and 3809 differentially expressed genes (DEGs) in groups S1 vs. S2, S2 vs. S3, S3 vs. S4, and S4 vs. S5, respectively. The Kyoto Encyclopedia of Genes and Genomes Enrichment Analysis (KEGG) demonstrated that the DEGs in the S1 vs. S2, S2 vs. S3, and S3 vs. S4 groups were enriched in the starch and sucrose metabolism pathways. Based on the transcriptome sequencing results, expression heat maps of genes correlated with the polysaccharide synthesis pathways of D. officinale clearly showed changes in the expression of polysaccharide synthesis-related genes at five stages. Using weighted gene co-expression network analysis (WGCNA), three co-expression modules were identified, showing a significant positive correlation with fluctuations in the water-soluble polysaccharide content. From the light blue module with the highest correlation coefficient, 15 key genes potentially closely related to polysaccharide synthesis were identified. This study provides gene resources for the genetic improvement of D. officinale and detailed reference data for further elucidating the molecular mechanisms of polysaccharide biosynthesis. Full article

Flower senescence during transport is a major concern for exporters, as physiological disorders reduce quality and price. Extending vase life is crucial, and while 1-MCP is widely used, it requires low temperatures and is less effective in disease control. Cold plasma generated by dielectric barrier discharge produces reactive oxygen and nitrogen species (RONS), offering an alternative method for preserving cut flowers. This study compared the effectiveness of cold plasma and 1-MCP treatments on the vase life of Vanda ‘Pachara Blue’ orchids. Flowers were treated with T1 (control at 25 °C), T2 (1-MCP), and T3 (cold plasma). Both 1-MCP and cold plasma significantly reduced ethylene production (26.15 and 25.20 µL C₂H₄/kg/hr, respectively) and respiration rate (63.92 and 57.44 mg CO₂/kg/hr, respectively) compared to the control (40.93 µL C₂H₄/kg/hr and 118.21 mg CO₂/kg/hr). Vase life was extended to 19.33 days in both treatments, an 87.12% increase over the control (10.33 days). Additionally, cold plasma slightly improved water uptake and reduced petal discoloration. These findings indicate that cold plasma is a promising alternative to 1-MCP, offering effective flower preservation without the need for low-temperature conditions and potential additional benefits in floral quality. Full article