Polyethylene Sheets Research Articles

Effect of high-temperature stress on rice grain quality

High-temperature stress (HS) due to global warming has become a serious threat to global food and nutritional security. Among the various agro-morphological and physiological changes observed in rice (Oryza Sativa L.) due to high-temperature sress, yield and grain quality are highly important and they vary among the germplasm. As reports on the effect of high-temperature stress on grain quality are less, rice grown under ambient as well as high-temperature conditions were subjected to important grain quality aspects to identify the least affected rice. Twenty-five entries were cultivated in two neighboring experimental plots, one for normal and the other for high-temperature stress (HS). High-temperature stress was imposed by enclosing the field-grown crop with a transparent polyethylene sheet supported by a metal frame at the onset of the reproductive phase. Temperature inside the above structure (treatment) as well as outside (control) was recorded until the crop was harvested. The mean minimum and maximum increase in temperatures were 0.67°C and 10.2°C respectively over the ambient conditions. After harvesting, all the paddy samples of both control and treatment were dried under shade and processed to brown rice which was manually separated into chalky and normal grains on a trans-illuminator. Further, total starch and protein contents were estimated separately in the chalky and normal grains of each sample. ANOVA indicated that temperature during the reproductive stage significantly (p<0.01) influenced the starch as well as protein contents. An increase in total starch content was observed in both normal and chalky grains under high-temperature stress. The difference in total starch amongst the genotypes was significant (p<0.01), however, the differences in total starch content between normal and chalky grain under both control and high-temperature stress condition was non-significant. Although the mean protein content for all the genotypes was not significantly affected in chalky and normal grains under control, it was reduced by >5% in chalky grains under high-temperature stress. Five entries noted £10% yield loss. Of these, IET29944 appears to be less affected in multiple parameters.

Radiation attenuation properties of chemically prepared MgO nanoparticles/HDPE composites

Sheets of high-density polyethylene (HDPE) loaded with magnesium oxide in micro and nano were synthesized with different weight percentages of micro-MgO (0,5,10,20 and 30% by weight) and nano-MgO (5 and 30%) and shaped in form of disc and dog bone shape. The morphological, mechanical, and attenuation characteristics of each concentration were determined. The linear attenuation coefficients (LAC) of the prepared discs were calculated using a well-calibrated scintillation detector and five standard gamma-ray point sources (241Am, 133Ba, 137Cs, 60Co and 152Eu). The LAC was theoretically calculated for HDPE/micro-MgO composites using XCOM software. A good agreement between the theoretical and experimental results was observed. The comparison between micro and nano-MgO as a filler in HDPE was evaluated. The results proved that the loaded nano-MgO in different proportions of HDPE produced greater attenuation coefficients than its micro counterpart. The addition of nano MgO with different weight percentage led to a significant improvement in the mechanical properties of HDPE, the ultimate force and ultimate stress increased as the concentration of nano MgO increased, and the young modulus of HDPE also increased with increasing concentration of micro and nano MgO.

Experimental investigation on the effect of soil solarization incorporating black, silver, and transparent polythene, and straw as mulch, on the microbial population and weed growth

Soil solarization is a non-chemical method for eliminating crop-threatening weeds and selectively decontaminating soil. The effect of various soil solarization with black, silver, transparent polythene sheet and straw as mulching on the microbial count and weed growth was studied experimentally. The farm investigation comprised six soil solarization treatments: mulching with black, silver, and transparent polyethylene sheets of 25 μm (μ), organic mulch (soybean Straw), weed-free, and control. All six treatments were repeated in four sets in a Randomized Block Design (RBD) plot size of 5.4 m × 4.8 m. Black, silver, and transparent polythene mulches significantly reduced fungal count compared to non-solarized soil. Straw mulch significantly increased soil fungal count. Solarized treatments had much lower bacterial populations than straw mulch, weed-free, and control treatments. Black, silver, straw mulch, and transparent polythene had 18746, 22763, 23999, and 3048 weeds ha−1 at 45 days after transplanting (DAT). The analysis of dry weed weight demonstrated a significantly low weed dry weight of 0.44 t/ha for black polythene (T1) based soil solarization, representing an 86.66% reduction in dry weed biomass. Soil solarization had the lowest weed index (WI), with black polythene mulch (T1) reducing weed competition. Among various soil solarization treatments, black polythene (T1) showed the highest weed control efficiency of 85.84%, indicating its suitability for use in weed control. The results suggest that soil solarization is effective for soil disinfestation and weed control with polyethene mulch and summer heat in central India.

Thermal Effect of Bobbin Tool Friction Stir Welding on the Mechanical Behavior of High Density Polyethylene Sheets: Experimental Study

Bobbin friction stir welding (BT-FSW) is a variant of the conventional friction stir welding (C-FSW). This method has been applied of welding high density polyethylene (HDPE) plates; where a rotating symmetrical tool causes a fully penetrated bond, it can weld the upper and lower surface of the work-piece in the same pass. BT-FSW process involves complex heat generation and HDPE flow, which directly affects on the weld area and on mechanical properties of welded joint. Heat generation and material flow during BT-FSW are significantly affected by the tool design features, process parameters and mechanical behavior of work piece materials. Studying the temperature of polyethylene sheets welded by BT-FSW can help in analyzing the mechanism of weld formation and also can provide theoretical guidance for the tool design, process parameter selection and even new process development. In the unique work described in this paper, the 11.4 mm-thick HDPE plates were welded successfully by bobbin-tool friction stir welding. Measurements of the material temperatures were performed by thermocouples which are placed near and at the weld seam. The weld quality was determined in terms of no defects in the stir zone and the tensile strength of the joint. It was found that considerable melting occurred between the rotating shoulders and on the trailing side of the rotating pin. Movement of the molten material by the rotating tool created a very black band in the stir zone. Thermocouples measurements indicated that the temperatures were higher on the advancing side (AS) compared to those on the retreating side (RS). Tensile tests and hardness measurements were performed on welded and seamless sheet samples. The results were analyzed to compare the mechanical properties. To demonstrate the variation in micromechanical properties between welded and seamless sheet samples, micro hardness (HV) testing was used to explain the difference. The HV of the HDPE plates weld by BT-FSW, were relatively symmetrical with respect to the parting line. The maximum hardness levels were reached in the weld bead at around 66 HV in the welded nugget; there was a rise in the level of hardness, in particular at retreating side (RS) and at advancing side (AS) where the value reached 68.60 HV.

Rapid Fabrication of Flexible Pressure Sensor Array

Flexible pressure sensor arrays are of increasing interest but their fabrication tends to be complex and time- consuming. In this work we propose an inexpensive, rapid fabrication approach for flexible pressure sensor arrays. The sensor consists of a matrix of pressure-sensitive resistive elements sandwiched by patterned electrode strips that are bonded to flexible tape substrates. The fabrication uses a commercially available vinyl-cutting machine to cut out patterned electrodes and sensing “pixels", from a copper tape sheet and a carbon-impregnated polyethylene sheet (Velostat), respectively, and it uses transfer tapes to facilitate the bonding of the electrodes to the adhesive tape substrates. The entire fabrication takes approximately 15 minutes, in contrast to several hours required with a previously reported approach for fabricating similar sensors. The spatial resolution achieved by the proposed method is also higher, with each sensing unit occupying an area as small as 3 mm by 3 mm. Due to the programmable nature of the cutting machine, the proposed method can be used to readily fabricate flexible sensors with versatile patterns. Various tests have been conducted to demonstrate the effectiveness of the fabricated sensors, with a 14-by-14 sensor array successfully mapping the pressure profiles under finger touch, loading of a hand sanitizer bottle, and grasping around a cup.

Effect of Cladding Material and Date of Transplanting on Growth and Yield of Greenhouse Broccoli During Winter in High Altitude Ladakh, India

Broccoli is a cool-season crop. The optimum temperature for initiation of flowering and head growth is 15-20°C. Due to subfreezing temperatures at night, the crop is not traditionally cultivated in winter in the high-altitude Ladakh region. We found that growing broccoli in a passive solar greenhouse in winter is feasible. The choice of greenhouse cladding material and the date of transplanting are important factors that need to be considered. The mean marketable head weight of the cv. Fiesta and KTS-1 in a passive solar trench greenhouse with polycarbonate cladding material transplanted on 8 September were 403±106 and 169±100 g, respectively. Delayed transplanting on 8 October did not produce any marketable head. Covering the greenhouse with a polyethylene sheet did not result in marketable heads on both transplanting dates. We anticipate our study to be a starting point for researchers and the farming community to optimize the greenhouse production of broccoli during freezing winter-months in high-altitude regions.

Teaching Models for Correct Rhombic Flaps.

The aim of this study was to introduce teaching models for correct rhombic flaps. For the line of maximal extensibility (LME) and flap design, surgical fabric (model 1), scored corrugated cardboard (model 2), and scored polyethylene sheet (model 3) were used. For choosing the correct flaps, a silicone face (model 4) was used. Seven participants in the Plastic Surgery Department were recruited for the workshop. In models 1 to 3, a 2-cm diameter circle and relaxed skin tension line were indicated. Participants were requested to design Limberg flaps. Each flap was elevated, transposed, and fixed with sutures (model 1) or cellophane tape (models 2 and 3). In model 4, a 1-cm diameter circle was indicated on the cheek. Participants were requested to design correct Limberg flaps. Although participants were not provided an article describing how to create correct Limberg flaps, they eventually created correct flaps through trial and error. Participants drew 2 parallel lines tangential to the defect and following the LME, perpendicular to the relaxed skin tension lines, which are the same as the scoring marks. They then drew 2 other sides of 2 possible parallelograms by tilting them medially and laterally with angles of 60 and 120 degrees each. Thus, 4 possible Limberg flaps to close the defect were drawn. Among the 8 possible flaps, 4 flaps that did not follow the LME were eliminated. Scored polyethylene sheet had the best extensibility and least distortion among the 3 models. Through this workshop, participants learned to design rhombic flaps correctly, using 2 parallel LMEs.

INDOOR WATER EFFICIENCY

India has 16% of the world’s population and only 4% of the world’s water resources, which are depleting rapidly. The demand for water is expected to grow from 40 billion cubic metres (bcm) currently to around 220 bcm in 2025. Water is one of the most important inputs essential for crops. Both its shortage and excess affect the growth and development of the plants, yields and quality of produce. There are numerous methods to reduce such losses and improve soil moisture. These are mulching, cropping, planting of trees, utilization of fog or dew by net-surfacing traps or polythene sheets, contour farming, transfer of water from surplus areas to deficit areas by inter-linking water systems through canals, desalination technologies such as distillation, electro-dialysis and reverse osmosis, use of efficient watering systems such as drip irrigation and sprinklers will reduce the water consumption by plants. The most important step in the direction of finding solutions to issues of water and environmental conservation is to change people's attitudes and habits; this includes each one of us Keywords: Water, conservation, technology, Rainwater- harvest, drip-irrigation.

Effect of Different Mulching Materials on Leaf Spot Disease of Groundnut

A study was conducted in summer season of 2020 and 2021 to evaluate the effect of different mulching materials on late leaf spot disease of groundnut caused by Phaeoisariopsis personata (Berk. & Curt.) v. Arx at Oilseed Research Program, Sarlahi, Nepal. The experiment was laid out in randomized complete block design (RCBD) with 7 treatments viz. rice husk, rice straw, black polythene sheet, Lantana camara, living mulch, sawdust and control in three replications with fertilizer dose 20:40:20 NPK kg per hectare. The disease was scored in 1-9 scale and severity and AUDPC was calculated. In 2020, Lantana camara mulched plot showed significantly the lowest disease severity and the lowest AUDPC value (66.67% and 1556) followed by rice husk (70.37% and 1556) and black plastic (70.37% and 1611) mulched plot. Similarly in 2021, Lantana camara mulched plot showed significantly lowest disease severity and the lowest AUDPC value (62.96% and 1500) followed by rice husk (66.67% and 1574) and black plastic (66.67% and 1574) mulched plot. Significantly the highest pod yield was obtained in rice husk mulched plot (2.35 t/ha in 2020 and 2.07 t/ha in 2021) followed by living mulch treated plot (2.13 t/ha in 2020 and 1.84 t/ha in 2021). The highest disease severity (81.4% same as rice straw and saw dust mulched plot) with highest AUDPC value (1981) was observed in plot with no mulch during 2020 where as in 2021, the highest disease severity (77.78 same as plot with no mulch) with highest AUDPC value (1889) was observed in rice straw mulched plot. This study shows that organic mulches like rice husk could be better option for reducing disease severity with better yield in groundnut.
 Int. J. Appl. Sci. Biotechnol. Vol 11(1): 37-41.

Nursing and management of early produced larvae of Thai pangas (Pangasianodon hypophthalmus) using greenhouse concept

This experiment was conducted for the development of nursing techniques of early produced larvae of Thai pangus (Pangasianodon hypophthalmus) using Greenhouse concept for a period of 40 days from 10th February to 20th March 2020. The experiment was designed into two treatments (i) Greenhouse pond (GP) and (ii) Control or open ponds (CP) having three replicates each. Greenhouse concept was used for increasing the temperature during the winter month for proper growth and survival of the spawn. For this purpose, three ponds were covered with transparent polyethylene sheet fastened into bamboo frame and three ponds with no such covering. All the nursery ponds were stocked at a density of 20 g hatchling/decimal with 3 days old P. hypophthalmus. After 40 days of nursing period, the highest mean final length, weight gain and survival rate of fry were found to be 9.75 cm, 12.44g and 73.19% in greenhouse pond where in Control ponds it was 6.39 cm, 7.22g and 58.08%, respectively. A significantly higher (p<0.05) mean gross production of 6.07 kg/ decimal was found in greenhouse pond where in Control ponds it was 2.80 kg/ decimal in 40 days of nursing period. Water quality parameters were found to be better with good primary production in the green house ponds due to retaining day light temperature by polyethylene sheet. Results from the present experiment indicated that greenhouse technique can be suitable for the nursing and management of early produced larvae of Thai pangas with proper growth and good survival rate.

Effect of mulch on yield of groundnut (Arachis hypogaea) in Nepal

Weeds are the most important biotic constraints to groundnut production in Nepal. They hinder the plant growth and increase the cost of production. A field based study was conducted from June, 2022 to December, 2022 at Oilseed Research Program, Sarlahi, Nepal to study the effect of mulch on the productivity of groundnut. The experiment was laid out in randomized complete block design with 7 treatments viz., rice husk, rice straw, black polythene sheet, Lantana camara, living mulch, sawdust and control in three replications. The fertilizer dose used for groundnut was 20:40:20 NPK kg per hectare. The pod yield in rice husk mulch and living mulch treatments were significantly higher (2.07 and 1.84 tons per hectare, respectively) whereas the lowest yield (0.83 tons/hectare) was observed in plot with no treatment). Lower weed infestation with weed biomass 0.046 tons/ha for narrow leaf weeds and 0.021 tons/ha for broad leaf weeds was observed in L. camara mulching. Rice husk mulching produced significantly higher number of pods (29 pods per plant) with the highest benefit cost ratio (1.15) whereas black polythene mulching produced lower number of pods (23 pods per plant) with lowest benefit cost ratio (-0.33). Conclusively, the study's finding suggests that rice husk can be used as a mulching material to increase the productivity of groundnut.

Attachment of potential cultivable primo-colonizing bacteria and its implications on the fate of low-density polyethylene (LDPE) plastics in the marine environment

Plastics released in the environment become suitable matrices for microbial attachment and colonization. Plastics-associated microbial communities interact with each other and are metabolically distinct from the surrounding environment. However, pioneer colonizing species and their interaction with the plastic during initial colonization are less described. Marine sediment bacteria from sites in Manila Bay were isolated via a double selective enrichment method using sterilized low-density polyethylene (LDPE) sheets as the sole carbon source. Ten isolates were identified to belong to the genera Halomonas, Bacillus, Alteromonas, Photobacterium, and Aliishimia based on 16S rRNA gene phylogeny, and majority of the taxa found exhibit a surface-associated lifestyle. Isolates were then tested for their ability to colonize polyethylene (PE) through co-incubation with LDPE sheets for 60 days. Growth of colonies in crevices, formation of cell-shaped pits, and increased roughness of the surface indicate physical deterioration. Fourier-transform infrared (FT-IR) spectroscopy revealed significant changes in the functional groups and bond indices on LDPE sheets separately co-incubated with the isolates, demonstrating that different species potentially target different substrates of the photo-oxidized polymer backbone. Understanding the activity of primo-colonizing bacteria on the plastic surface can provide insights on the possible mechanisms used to make plastic more bioavailable for other species, and their implications on the fate of plastics in the marine environment.

Productivity Enhancement of Total-Cross-Tied PV Array Under Static Shade Conditions

Mismatch losses, hotspot creation, lower power production, and the occurrence of multiple peaks are the major impacts of the partial shading in a photovoltaic (PV) array. To mitigate the shading effect, this article introduces a Parquet SuDoKu-based static array reconfiguration approach and validates it using an experimental investigation. This concept is initially tested on a 9 × 9 PV array via simulations under five shade patterns before being implemented on a 3 × 3 hardware prototype. In an effort to perform a hardware execution, artificial shade is devised with commercially available polythene sheets and synthetic soiling. This method improved overall efficiency while significantly reducing losses. Also, performance study and a technoeconomic analysis are conducted in support of this assertion.

Biodegradation of Oil-Based Plastic Wastes by Bacteria Isolated from Fish Breeding Tanks

Several studies have shown that certain microbes, mainly bacteria may have the ability to digest plastic wastes. The goal of this study was to see how well Bacillus subtilis, Staphylococcus lentus, Aeromonas hydrophila, Sphingomonas paucimobilis and Kocuria paedia degrade three kinds of oil-based plastics: low-density polyethylene (LDPE), polystyrene (PS) and polyvinylchloride (PVC) polymer sheets. The experiment was conducted for 30 days under laboratory conditions with occasional shaking at 180 rpm and 32°C. Biodegradation was measured in terms of weight loss.. Accordingto IR Spectroscopy, the C-H stretch band at 2920cm-1 improved as a result of bacterial degradation of polyethylene. The most affected polymers were LDPE and PVC films. While PS films were the least affected polymers. B. subtilis was shown to be the most successful of the five bacterial species, whereas K. paedia was determined to be the least effective.

Ultra-High Molecular Weight Polyethylene Modifications Produced by Carbon Nanotubes and Fe2O3 Nanoparticles.

Thin sheets of ultra-high molecular weight polyethylene (UHMWPE), both in pristine form and containing carbon nanotubes (CNTs) or Fe2O3 nanoparticles (NPs) at different concentrations, were prepared. The CNT and Fe2O3 NP weight percentages used ranged from 0.01% to 1%. The presence of CNTs and Fe2O3 NPs in UHMWPE was confirmed by transmission and scanning electron microscopy and by energy dispersive X-ray spectroscopy analysis (EDS). The effects of the embedded nanostructures on the UHMWPE samples were studied using attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy and UV-Vis absorption spectroscopy. The ATR-FTIR spectra show the characteristic features of the UHMWPE, CNTs, and Fe2O3. Concerning the optical properties, regardless of the type of embedded nanostructures, an increase in the optical absorption was observed. The allowed direct optical energy gap value was determined from the optical absorption spectra: in both cases, it decreases with increasing CNT or Fe2O3 NP concentrations. The obtained results will be presented and discussed.

X-ray diffractometric study of HDPE/GaAs and HDPE/GaAs<Te> composites

High-density polyethylene sheets (HDPE), HDPE/GaAs and HDPE/ GaAs<Te> composites with GaAs and GaAs<Te> semiconductor fillers were studied by X-ray diffractometry at room temperature. The degree of crystallization of these samples was calculated and it was determined that the inclusion of fillers in the polymer matrix (x=1-10% composite) leads to an increase in the degree of crystallization by 1.3-1.4 times. The obtained results are explained by the change of the upper molecular structure of the polymer.

Minimizing the Main Strains and Thickness Reduction in the Single Point Incremental Forming Process of Polyamide and High-Density Polyethylene Sheets

Polymeric materials are increasingly used in the automotive industry, aeronautics, medical device industry, etc. due to their advantage of providing good mechanical strength at low weight. The incremental forming process for polymeric materials is gaining increasing importance because of the advantages it offers: relatively complex parts can be produced at minimum cost without the need for complex and expensive dies. Knowing the main strains and especially the thickness reduction is particularly important as it directly contributes to the mechanical strength of the processed parts, including in operation. For the design of experiments, the Taguchi method was chosen, with an L18 orthogonal array obtained by varying the material on two levels (polyamide and polyethylene) and the other three parameters on three levels: punch diameter (6 mm, 8 mm and 10 mm), wall angle (50°, 55° and 60°) and step down (0.5 mm, 0.75 mm and 1 mm). The output parameters were strain in the x direction, strain in the y direction, major strain, minor strain, shear angle and thickness reduction. Two analyses were conducted: signal-to-noise ratio analysis with the smaller-is-better condition and analysis of variance. The optimum values for which the thickness was reduced were the following: wall angle of 50°, punch diameter of 10 mm and step down of 0.75 mm.

Investigation of welding defects in friction stir spot welding of plastics

In friction stir spot welding applications, there are some factors that provide welding strength, welding performance and the formation of defects that may occur in welding. Among these factors, machine parameters and welding tool design should be compatible with each other. If these factors are not chosen appropriately, the welding will not be of the desired quality. In this study, high density polyethylene sheets were joined using friction stir spot welding technique. It has been determined that some of the joints made have low weld strength, defects on the weld surface and around the stir zone. By investigating the causes of these defects, suggestions were made to prevent these defecs It has been observed that these defects are not repeated in the welds made with the suggestions made and it has been determined that high weld strength can be obtained. The highest weld strength and performance were obtained by 0.2–0.4 mm plunge depth, 45–60 s stirring time, 700–900 tool rotation speed and 30 mm shoulder diameters. In order to obtain a perfect weld in friction stir spot welding, it was determined that a homogeneous mixture should be formed between the stirring zone and the thermo-mechanically affected zone. Low weld strength was obtained in all joints with defects detected in these regions. Low weld strengths and weld defects were detected at dwell times of less than 30 s, at all tool rotational speeds with a stirring time of less than 45 s, at a plunge depth greater than 0.4 mm, and at low tool rotation speeds.

Effect of Greenhouse Film Cover on the Development of Fungal Diseases on Tomato (Solanum lycopersicum L.) and Pepper (Capsicum annuum L.) in a Mediterranean Protected Crop

Greenhouses on the Mediterranean coast mainly use plastic materials as their cover. The influence of light exerted by these materials directly affects the crops by modifying the environment in which they develop. The aim of this study was to analyze the effect of the use of two plastic films in an experimental greenhouse on the development of fungal diseases in two spring–summer crop cycles: tomato (Solanum lycopersicum L.) from February to July 2021 and pepper (Capsicum annuum L.) from February to July 2022. The study was carried out in Almeria (Spain) in a multispan greenhouse divided transversely into two sectors by a polyethylene sheet. A commercial film was installed in the east sector (90% of transmissivity and 55% diffusivity) and an experimental film was installed in the west sector (85% of transmissivity and 60% diffusivity). In addition, the effect of the yield and quality of the harvested fruit was determined. In this study, two diseases were established naturally on the crop: (i) powdery mildew (Leveillula taurica) in both the tomato and the pepper crop cycles and (ii) early blight (Alternaria solani) in the tomato. The analyses of both diseases showed that the areas of the greenhouse that used the plastic cover, which presented a lower sunlight transmissivity, showed higher levels of disease than the areas that used the plastic cover that allowed greater transmissivity of light within the greenhouse, differing statistically in some phases of the crop. The marketable yield was 4.2% (for tomato) and 3.1% (for pepper) higher in the sector with the experimental film with high transmissivity. For both crops, the quality of the fruits did not show statistically significant differences.

A novel synthesis of light transmission from upcycled polyethylene terephthalate polymer and low-density polyethylene for greenhouse design in tropical climate

Abstract To support the circular economy in Thai’s agriculture, the main interviewed challenges point to knowledge and knowhow for greenhouse structure and system boosting up productivities. One popular material that possibly affected productivity is transparent polymer film, which can be recycled based on material property and blowing machine condition. This paper investigates the light transmittance performance of transparent polyethylene terephthalate polymer (PET) and low-density polyethylene (LDPE) sheets for use in low-energy greenhouses in tropical climates. The aim of the study is to optimize the thermal performance and light transmittance of these materials to support plant growth and human comfort. The study focuses on seven stages of plant growth, each of which requires different light characteristics including 1) seed, 2) germinating, 3) young seedling, 4) older vine, 5) flowering, 6) fruit bearing and 7) harvesting and drying. Each stage requires different light characteristics, e.g. light intensity, red light, blue light, white light and ultraviolet (UV) and pulsed light (PL). The methodology involves selecting PET and LDPE materials, preparing samples for thermal property and lighting laboratory tests and analysing the results based on suitable criteria. The findings show that LDPE sheets have 28.78% lower light transmittance than PET sheets, making them suitable for supporting the seedling stage and older vines of plant growth. PET sheets, on the other hand, deliver a high intensity of red light, making them suitable for stimulating photosynthesis in older vines and during the harvesting process. The study highlights the importance of considering both thermal performance and light transmittance when selecting materials for low-energy greenhouses in tropical climates.