Search Results (465)

Increasing planting density is an effective strategy for improving maize (Zea mays L.) productivity, but it can also intensify interplant competition and canopy shading. Enhanced nitrogen application may help offset these negative effects. A two-year field experiment was conducted in the Hexi Corridor, an arid region of northwestern China, using a full factorial design with three planting density levels D1 (75,000 plants ha⁻¹), D2 (90,000 plants ha⁻¹), and D3 (105,000 plants ha⁻¹), and three nitrogen application levels N1 (198 kg ha⁻¹), N2 (264 kg ha⁻¹), and N3 (330 kg ha⁻¹). The aim was to clarify how the interaction between planting density and nitrogen application regulates maize canopy structure and affects resource use efficiency in arid areas. The results showed that planting density, nitrogen rate, and their interaction significantly affected canopy structure, photosynthetic traits, grain yield, and water and nitrogen use efficiency. From the perspective of each growth stage, combinations of medium and high planting density and nitrogen application levels facilitated the optimization of maize canopy structure, promoted plant growth and dry matter accumulation, and elevated leaf SPAD values. Meanwhile, treatment D2N2 exhibited the most prominent improvement in maize yield components, with grain yield increased by 1.44–35.58% on average across experimental years. This treatment also sustained superior water and nitrogen use efficiency, achieving an average water use efficiency of 3.53 kg·m⁻³ and an average partial factor productivity of nitrogen of 53.41 kg·kg⁻¹. Comprehensive multi-index evaluation verified that D2N2 represented the optimal cultivation regime. This regime could reduce nitrogen fertilizer input by 20% while fully exploiting light and heat resources inherent to arid regions. Collectively, this study establishes a viable green and high-efficiency cultivation paradigm for maize production with high yield, reduced fertilizer input and water conservation, and delivers critical theoretical and technical references for the sustainable intensification of maize cultivation in arid regions of northwest China. Full article

This study deals with the influence of the pressure steaming process on color changes and acidity development in the heartwood and sapwood zones of pine wood (Pinus sylvestris L.). The hydrothermal treatment was carried out in a pressure autoclave under two different technological modes: Mode I (105 °C) and Mode II (120 °C) with exposure times of 6 and 18 h. The results showed that steaming causes a demonstrable decrease in wood moisture immediately after treatment, which is a consequence of self-evaporation during autoclave decompression. Colorimetric analysis in the color space CIE L*a*b* revealed a progressive darkening (decrease in L*) and a shift towards warmer, red-yellow shades (increase in a* and b*) in both anatomical zones. Optimal visual homogenization, in which the color contrast between sapwood and heartwood practically disappears, was mathematically achieved in Mode I after 18 h of exposure. In parallel, deep acidification occurred, when pH values decreased from initial native levels (4.7 for heartwood and 5.1 for sapwood) to a minimum of 4.0 and 4.1, respectively. Two-factor analysis of variance confirmed that steaming temperature and exposure time are statistically highly significant factors (p < 0.001 and p < 0.01, respectively) influencing the pH decrease, which is primarily caused by the thermal autohydrolysis of hemicelluloses and the subsequent release of free acetic acid. These findings provide key optimization parameters for industrial wood staining and subsequent surface treatment processes. Full article

Blue Vanda hybrids, including Vanda ‘Pakchong Blue’, frequently fail to flower during Thailand’s hot season (March–May), resulting in reduced market supply despite strong commercial demand. This study investigated flowering behavior and the effects of temperature management on growth, flowering, and flower quality of Vanda ‘Pakchong Blue’. In the first experiment, flowering behavior was examined through weekly histological observations of plants maintained under high-temperature conditions following inflorescence removal. Floral buds were initiated under high temperatures but failed to complete development and subsequently aborted. The period from floral initiation to anthesis was approximately 75 days. In the second experiment, plants were subjected to low-temperature treatments (18 ± 2 °C) for 0, 4, or 6 weeks and subsequently transferred to either an evaporative-cooling greenhouse (ECG) or a shaded greenhouse (SG). Plants grown in the ECG flowered during the off-season (March–May), whereas those grown in the SG flowered during the natural flowering season (August–September). Flowering in the ECG occurred 136–156 days earlier than in the SG and produced superior flower quality, including longer inflorescences and a greater number of florets. Exposure to 18 °C for 4 and 6 weeks delayed flowering by 24 and 45 days, respectively, but had no significant effect on vegetative growth. These findings demonstrate that successful off-season flowering and improved flower quality were primarily associated with cultivation in the evaporative-cooling greenhouse, whereas prolonged exposure to 18 °C delayed flowering without affecting vegetative growth. This study provides the first detailed characterization of floral bud development and flowering responses to different temperature-management strategies in this cultivar and highlights the potential of evaporative-cooling greenhouse technology for sustainable orchid production, climate-resilient floriculture systems, and year-round supply of high-quality flowers under tropical conditions. Full article

Shading nets are increasingly used in warm-climate vineyards to mitigate excessive cluster exposure. However, relatively few studies have evaluated their effects on fruit-zone microclimate and berry composition. This single-season field study evaluated the effects of conventional and photoselective shading nets in Cabernet Sauvignon on cluster-zone radiation, thermal conditions, bunch sunburn and powdery mildew percentage, berry maturity, and free amino acid content. Shading treatments significantly modified incident photosynthetically active radiation in the bunch zone, while air-temperature-derived thermal indices were not significantly affected. The conventional black Raschel net produced the greatest reduction in incident radiation, but this reduction was not associated with a decrease in sunburn or powdery mildew severity in bunches. The gray–pearl photoselective net maintained intermediate radiation levels and showed a lower severity of sunburn and powdery mildew, together with higher must pH and lower berry arginine content. The black–white photoselective net reduced berry soluble solids, while the conventional Raschel net increased berry histidine content, indicating that berry maturity and amino acid responses were treatment-dependent. These results provided preliminary field evidence on the effects of shading nets on Cabernet Sauvignon bunch sanitary and berry composition. Therefore, further multi-season and multi-site studies are needed before broader recommendations on shading-net use in warm-climate vineyards. Full article

The goal of agrivoltaic engineers is to use growing space for the synergistic production of both food and energy, typically via photovoltaic (PV) capture. Most research in this area has been carried out in arid, high-light environments, but subtropical and temperate regions are also critical production zones, and installation designs vary considerably. In this study, tomato and lettuce production using an agrivoltaic high tunnel (HT) design specific for a subtropical environment (NE Georgia, USA, USDA Zone 8A) was tested using organic production standards. The design utilized typical HTs (approx. 11 m × 5 m) with solar panel arrays hung internally. The design aimed to (1) meet off-grid power needs, (2) mitigate excessive temperature and humidity, (3) balance shade and plant productivity, and (4) simplify installation and maintenance. Treatments were replicated at the HT level, and cultivar differences were assessed to identify genotypes that might serve in future work to optimize yield under partial shade. In 2023 and 2024, we employed novel organic photovoltaic (OPV) panels, which are partially opaque. The OPV panels provided sufficient energy needs to maintain beneficial conditions without external power sources. In 2024, tomato plants in the OPV HTs experienced an area-weighted daily light integral (DLI, mol photons m⁻² d⁻¹) of approximately 31.8 (95% CI [28.9, 34.7]), compared to 34.7 (95% CI [31.8, 37.6]) in non-OPV HTs, an approximate reduction of 8%. Average maximum temperatures in the OPV HTs were 33.5 °C (95% CI [30.6, 36.4], compared to 35.1 °C (95% CI [30.9, 39.2]) in the non-OPV HTs, an approximate reduction of 1.6 °C. In 2023, tomato marketable yield was reduced by approximately 0.9 kg per plant in OPV HTs compared to non-OPV HTs (p = 0.023). In 2024, yields were statistically equivalent across all treatments (p > 0.1), while marketable fraction was improved relative to 2023 and was greatest in the HTs. Lettuce yield for both years was unaffected by the presence of HTs or OPV panels (p > 0.1). In 2025, we conducted an additional experiment using a shade-equivalent array of conventional 100% opaque photovoltaic (PV) panels and observed a similar reduction in DLI and no significant impact on tomato yield parameters (p > 0.1 Both designs were effective at equilibrating conditions inside the HTs to ambient temperature levels outside the tunnels. Using results from the study, an app for agrivoltaic value estimation was developed. Based on that software, the presented agrivoltaic design under currently available silicon–PV technology achieves an 18% annual return, assuming system depreciation is minimal and surplus energy could be applied to other on-farm needs. Full article

Cocoa agroforestry is widely promoted for biodiversity conservation and sustainable production; however, uncertainties remain regarding the distribution of epiphytes and cocoa yield under different shade regimes. This study evaluated the effects of shade on epiphyte distribution and cocoa productivity at two community sites located approximately 6 km apart. One site consisted of cocoa cultivated under indigenous and introduced shade trees, while the other site used a 40% shade net. Annual rainfall at the sites was 1364.70 mm and 1178.44 mm, respectively, with average monthly temperatures ranging from 28 to 35 °C. During the main dry season, light intensity under direct sunlight exceeded 13.00 Klux and was approximately three times greater than in shaded plots. Lichens were the dominant epiphytes across all shade systems, with 40–70 colonies per 225 m² plot. Only one vascular epiphyte species was recorded, occurring exclusively on cocoa trees under the shade net. Correlation coefficients between light availability and epiphyte abundance ranged from 0.08 to 0.62, indicating that light influenced epiphyte distribution and diversity. Cocoa pod production under indigenous shade trees and full sunlight was comparable (127–177 pods per plot), whereas production under the shade net was approximately twice that recorded in unshaded plots. Although flower cushion abundance varied among treatments, pods from shaded plots generally contained more beans. The highest incidence of diseased and wilted pods occurred under shade trees. Overall, the findings suggest that heavy tree shade may limit epiphyte development through reduced light availability, while uniform artificial shading may enhance cocoa yield. Full article

Malania oleifera is an endangered woody oil tree species endemic to China, where light conditions play a key role in seedling establishment. However, responses of seedling-associated bacterial communities to shading remain poorly characterized. This study investigated phyllosphere and rhizosphere bacterial communities under different shading regimes using 16S rRNA amplicon sequencing in two-year-old seedlings. Seedlings were subjected to 75%, 50%, and 25% shading, full-light conditions, and a field-grown reference group. The phyllosphere bacterial community showed lower alpha diversity and stronger compositional variation across shading treatments than the rhizosphere community, indicating higher sensitivity of leaf-associated bacteria to changes in the light environment. The rhizosphere maintained a larger shared bacterial pool and more stable community composition, with treatment-related differences mainly reflected in shifts in relative abundance. Functional prediction using PICRUSt2 indicated that phyllosphere bacterial functions were more responsive to shading than those in the rhizosphere, particularly pathways associated with genetic information processing and metabolism. PICRUSt2-based KEGG predictions suggested that both the phyllosphere and rhizosphere communities in the less-shaded and unshaded treatments were enriched for pathways related to aromatic compound degradation. Co-occurrence network analysis further revealed that phyllosphere association patterns were more sensitive to shading variation, whereas rhizosphere network complexity remained relatively stable. Shading exerted compartment-specific effects on the bacterial communities of M. oleifera seedlings, with the phyllosphere microbiota showing higher sensitivity to light variation than the rhizosphere communities. Full article

Horqin Sandy Land suffers from desertification, drought, and low fertility, limiting soybean production. Agrivoltaics provides a promising integrated model; however, the effects of agrivoltaics combined with water–fertilizer management on crop productivity remain unclear. A 2-year field experiment was conducted in a semi-arid area with three treatments, open-field control (Open), shaded area under panels (Under), and light-exposed area inter-panels (Gap). Results showed that photovoltaic systems combined with integrated water–fertilizer management improved soybean yield, soil water, and nutrient conditions. Soybean grain yield was 60.7% and 38.2% higher in the Gap and Under treatments, respectively, than in the Open. The highest yield in the Gap treatment resulted from both enhanced photosynthesis and improved root development. The Under endured light stress but exhibited morphological plasticity (plant height and leaf area increased by 43.1%, 48.2%), and shading alleviated water stress since soil water content was increased by 81.6–119.0% during growing seasons, transpiration rate (Tr) decreased by 55.1%, and leaf water use efficiency (WUE) increased by 48.8%. The Open suffered from soil degradation and water and fertilizer loss, resulting in severely limited yield. Agrivoltaics increased net income by 1466 CNY·ha⁻¹ and improved soil nutrients, demonstrating economic and ecological benefits. Thus, it is a suitable technical model for semi-arid sandy regions. Full article

Integrating semi-transparent photovoltaics (STPV) into greenhouse structures offers an effective approach to optimizing the Food–Energy Nexus and maximizing sustainable land-use efficiency. However, a knowledge gap remains regarding how specific STPV spectral signatures drive plant morpho-physiological acclimation across multiple cultivation cycles. This study presents a 19-month multi-cycle, proof-of-concept evaluation of the structural growth dynamics and physiological responses of generative (tomato) and vegetative (lettuce) crops under greenhouse prototypes with two distinct thin-film STPV technologies: Cadmium Telluride (CdTe) and amorphous Silicon (a-Si), compared to an unshaded transparent control. Biometric monitoring revealed that morphological acclimation (Shade-Avoidance Syndrome) was highly plastic, driven by the interplay between spectral filtering and seasonal irradiance limits. While structural adaptations, such as foliar expansion and stem elongation under the a-Si spectrum, were pronounced during specific transitional seasons (e.g., early spring), these morphological differences largely homogenized across treatments during periods of extreme high or low natural irradiance. Despite the shading penalty, this morphological acclimation successfully sustained agronomic fresh mass. Systemic efficiency, quantified by the Land Equivalent Ratio (LER) as a relative biophysical synergy index, demonstrated notably crop-specific synergies. Under an extended single fruiting cycle, the CdTe prototype showed potential to improve yield, achieving a maximum LER of 1.66 for the high-light-demanding tomato (Y_crop = 1.40). Conversely, the a-Si module excelled with the shade-tolerant lettuce during early vegetative stages in high-radiation periods, achieving peak LERs up to 1.55. These findings provide a biophysical baseline to help guide future scalability assessments prior to full-scale commercial agrivoltaic (APV) implementation for sustainable food systems. Full article

Intercropping systems are beneficial for resource utilization; however, the spatial proximity of companion species leads to competition for shared resources, particularly light. A walnut–potato intercropping model was established to understand the photosynthetic and physiological mechanisms underlying yield and marketability responses. Three intercropping treatments were established based on the number of potato ridges between walnut tree rows: B1 (three ridges), B2 (five ridges), and B3 (seven ridges). All intercropping and monoculture (CK) plots used an identical double-row planting pattern per ridge. Results showed that ridge density induced significant physiological changes and yield impacts. Compared to CK, B3 significantly reduced soluble protein content, net photosynthesis (Pn), and antioxidant enzyme activities (SOD, CAT), while B1 and B2 showed intermediate, non-significant reductions. Peroxidase (POD) activity increased progressively with ridge number (B3 > B2 > B1 > CK), indicating dose-dependent shade stress. Intercellular CO₂ concentration (Ci) was significantly elevated under all intercropping treatments, suggesting a predominantly non-stomatal, biochemical limitation on photosynthesis rather than water stress. Yield was highest in CK, followed by B1 and B2—which were statistically comparable to CK—while B3 yielded the least due to severe shading. Marketability declined sharply in B3, with fewer than half of tubers reaching commercial grade. Multivariate analysis showed distinct clustering of yield-associated variables (Pn, protein, marketability) separate from shade-stress indicators (POD, Ci) across treatments. These findings provide practical and scientific evidence to optimize walnut–potato intercropping configurations under the arid conditions. Full article

Watermelons account for 7% of the world’s fruit vegetable production. In the European market, Spain contributes around 35% of total watermelon supply, with the majority grown in greenhouses in Almería, Southern Spain. This study presents experimental results from the first agrivoltaic watermelon trial conducted in a raspa-y-amagado greenhouse during the 2024 growing season in Almería, Spain. Watermelons were cultivated under two shading treatments with 30% and 50% of the roof area covered with PV modules and compared against an unshaded control group. Throughout the experiment, temperature values in the 30% and 50% zones were 2.2 °C and 4.3 °C lower than in the control zone, respectively. The unshaded control zone and the 30% shading treatment maintained DLI conditions within the optimal range between 21 mol m⁻² d⁻¹ and 32 mol m⁻² d⁻¹ for most of the crop cycle, while the 50% shading zone remained largely above the minimum threshold of 15 mol m⁻² d⁻¹ required for adequate crop growth. No statistically significant differences were observed in fruit weight, rind width, fruit firmness, or soluble solids content at harvest. In addition, the experimentally measured irradiance data from this study were compared with simulations from a previously established irradiance model. The model was applied to the raspa-y-amagado greenhouse, and the experimental data were used to perform a long-term comparison between simulated and measured irradiance for 265 days of data. The irradiance model accurately reproduced shading effects from both the PV modules and greenhouse structure, achieving nRMSE values of 0.09, 0.18, and 0.27 for the control, 30% shading, and 50% shading zones, respectively. Full article

Buildings account for a significant share of global energy consumption and carbon emissions, creating an urgent need for advanced energy retrofit technologies. This review critically examines the role of plasma-modified textile polymer materials in improving the energy efficiency and durability of building retrofit systems. Various textile polymers, including polyester (polyethylene terephthalate, PET), polypropylene (PP), polytetrafluoroethylene (PTFE), polyamide (PA), and fiber-reinforced composites, are evaluated in relation to plasma surface engineering approaches, including atmospheric plasma, dielectric barrier discharge (DBD), and plasma jet treatment. Reported studies demonstrate that plasma treatment significantly alters surface morphology and chemistry, resulting in increased surface roughness, enhanced wettability, improved coating adhesion, and superior hydrophobic behavior. Water contact angles increased from approximately 70° to 145° depending on polymer type and plasma conditions, while reflective coating performance improved with solar reflectance enhancements of approximately 10–15%. Plasma-treated reflective roofing and shading textiles also showed reductions in building cooling energy demand of approximately 18–25% and roof temperature decreases of 10–15 °C. Furthermore, plasma-induced surface activation improved durability, ultraviolet (UV) resistance, and weather stability of textile membranes used in facade and roofing applications. The review also discusses industrial challenges related to scalability, plasma aging effects, energy consumption, and long-term performance. Plasma-modified systems demonstrate strong potential for multifunctional, lightweight, and sustainable building envelope technologies for future energy-efficient construction. Full article

Light intensity and spectral composition regulate plant physiological processes and productivity, particularly under low-light greenhouse conditions. This study was designed to address two main objectives in aeroponically grown potato (Solanum tuberosum L. cv. Agria). First, we evaluated the effects of supplemental light quality, focusing on different red (R), blue (B), and white (W) combinations at a constant intensity of 100 μmol m⁻² s⁻¹. Second, we assessed the specific effects of far-red (FR) light on plant performance and biomass allocation patterns. Potato plants were grown under greenhouse conditions in a completely randomized design consisting of eight supplemental LED spectral treatments and a natural-light control. Supplemental lighting increased net photosynthesis, stomatal conductance, chlorophyll content, and biomass compared to the control, demonstrating that moderate increases in light intensity improved plant performance under low-light conditions. Among the spectral treatments, W light and balanced R–B combinations increased net photosynthetic rate by 93.7–198.7% and total biomass by 23.8–132.1% relative to the control, suggesting improved coordination of stomatal activity, electron transport, and chlorophyll biosynthesis under the experimental light environment. In contrast, FR inclusion reduced the net photosynthetic rate and mini-tuber biomass by 15.0–38.6% relative to the corresponding FR-free treatments, particularly under treatments with lower red proportions, suggesting that FR effects are more likely associated with phytochrome-mediated regulation of photosynthetic efficiency and assimilate partitioning under modified red to far-red spectral balance rather than classical shade-avoidance responses. Mini-tuber yield was strongly affected by light treatments. White light and balanced R:B spectra produced the highest tuber number and biomass, increasing mini-tuber number and biomass by 26.6–62.5% and 15.4–87.7%, respectively, compared with the control, whereas FR reduced yield. Although FR appeared to increase the relative allocation of biomass to tubers, overall photosynthetic performance and biomass accumulation remained lower, resulting in lower productivity. Overall, mini-tuber production appeared to be associated with source–sink relationships, where light intensity enhanced photosynthetic performance and biomass production, light quality optimized photosynthetic performance, and FR light appeared to modify biomass allocation patterns. These findings highlight the importance of optimizing spectral composition and FR management in aeroponic seed potato production under low-light greenhouse conditions. Full article

Outdoor thermal comfort models are generally developed for healthy populations and may not be directly applicable to patients with altered thermoregulatory capacity. This study examined summer outdoor thermal responses of lung cancer patients in Shenyang, China, focusing on differences by treatment modality and disease stage. Field microclimatic measurements and questionnaire surveys were conducted in four typical outdoor microenvironments: waterfront place, tree-shaded space, open square, and enclosed porch. A total of 706 lung cancer patients were surveyed and stratified by treatment modality and disease stage. Physiologically equivalent temperature (PET) was calculated using RayMan Pro based on measured air temperature, mean radiant temperature, air velocity, relative humidity, clothing insulation, and activity-based metabolic rate. Subgroup differences were observed in neutral PET and thermal comfort ranges. Chemotherapy patients had the highest neutral PET at 26.0 °C, while immunotherapy patients had the lowest at 22.6 °C. Radiotherapy, surgery, and targeted therapy groups showed neutral PET values of 23.3 °C, 23.7 °C, and 24.5 °C, respectively. Early-stage patients had a neutral PET of 23.8 °C, whereas late-stage patients showed a higher value of 25.8 °C and a narrower neutral range of 23.1–28.5 °C. The surgery group had a broad acceptable PET range of 20.5–28.6 °C, while the late-stage group had a narrower range of 24.7–26.8 °C. Preferred temperature was also higher in the chemotherapy and late-stage groups. These findings indicate heterogeneous summer outdoor thermal responses among lung cancer patients and provide empirical evidence for subgroup-sensitive thermal assessment and outdoor space design near healthcare facilities. Full article

The yield, chemical profile and antioxidant activity of sage (Salvia officinalis L.) essential oils (SEOs) isolated from shaded (pearl-, red- and blue-colored nets) or non-shaded plants from three different harvest-time phenological stages (May, August and September) investigated. Both main effects and their interactions were highly significant (p < 0.01). Blue nets produced the highest yield in the first (4.09 mL/100 g) and second (3.29 mL/100 g) harvests, significantly exceeding all other treatments within the same harvest period. In the third harvest, unshaded control plants achieved the highest yield (3.55 mL/100 g). The total number of individual SEO components varied depending on the harvest time and shading treatment (27–35). The most abundant components were thujone (cis-thujone, 24.1–36.1%; trans-thujone, 4.9–13.1%) camphor (20.0–30.2%) and 1,8-Cineole (8–11%). The content of undesirable component camphor was the lowest in all three harvests in plants covered with blue shading nets. FRAP values ranged from 0.462 mg Fe²⁺/g oil (second harvest, red net) to 1.151 mg Fe²⁺/g oil (first harvest, red net), while EC₅₀ values ranged from 9.169 mg/mL (first harvest, red net) to 37.004 mg/mL (third harvest, blue net). The third-harvest blue-net sample exhibited one of the highest FRAP values (1.123 mg Fe²⁺/g oil) yet the weakest DPPH radical scavenging activity (EC₅₀ = 37.004 mg/mL), reflecting different mechanisms of antioxidant action between the two assays. In conclusion, the highest yield and best quality of EO were achieved in the first harvest. Shading the plants, particularly with blue nets, contributed to an increase in EO yield, as well as improved EO quality, including higher thujone content and lower content of undesirable camphor. Covering the plants with blue nets during the first and second harvest periods enhanced essential oil yield and quality. In the third harvest, open-field conditions favored a higher yield; however, blue-net shading produced the lowest camphor content (20.3%), which may be advantageous for pharmaceutical applications. The choice of whether to maintain or remove nets during the third harvest should therefore be guided by the intended end use of the essential oil. Full article