scholarly journals Influence of different light sources on the production process of tomato in intensive photoculture

2021 ◽  
pp. 65-70
Author(s):  
T. E. Kuleshova ◽  
O. R. Udalova ◽  
I. T. Balashova ◽  
L. M. Anikina ◽  
P. Yu. Kononchuk ◽  
...  

Introduction. The development of ideas about the influence of the light environment - the radiation spectrum, intensity and duration of exposure, on the physiology of plants, serves as the basis for the creation of effective light sources for protected ground.Purpose. Comparative test of the influence of a light environment with different spectral composition on the productivity and quality of tomatoes in conditions of intensive photo culture.Methods. Investigations were made under controlled conditions of intensive photoculture when growing dwarf tomatoes of the variety Natasha selections of the “Federal Scientific Vegetable Center” on thin-layer soil analogs with the supply of a nutrient solution to the plant roots through a slit capillary in vegetative light installations developed at the ARI. The light sources were high-pressure sodium lamps and LED lamps SD1, SD2, and SD3 with different emission spectra. Results. Tomatoes of the Natasha variety, illuminated during development with HPS lamps, formed almost the same yield with an average fruit weight of 42.5 kg/m2 per layer per year. Natasha tomato grown under LED lamps showed a tendency to lower productivity by 29% under SD1 and by 8% under SD2 and higher by 19% under underSD3 compared to that under HPS lamps. A comparative assessment of the biochemical composition of tomato fruits indicates their high quality under all tested light sources.Conclusion. Cultivation of dwarf tomato varieties on thin-layer soil analogs showed the best results in terms of productivity with good quality plant products under LED lamps SD3 with a radiation spectrum close to sunlight.

2020 ◽  
pp. 89-96
Author(s):  
Sergei S. Kapitonov ◽  
Alexei S. Vinokurov ◽  
Sergei V. Prytkov ◽  
Sergei Yu. Grigorovich ◽  
Anastasia V. Kapitonova ◽  
...  

The article describes the results of comprehensive study aiming at increase of quality of LED luminaires and definition of the nature of changes in their correlated colour temperature (CCT) in the course of operation. Dependences of CCT of LED luminaires with remote and close location of phosphor for 10 thousand hours of operation in different electric modes were obtained; the results of comparison between the initial and final radiation spectra of the luminaires are presented; using mathematical statistics methods, variation of luminaire CCT over the service period claimed by the manufacturer is forecast; the least favourable electric operation modes with the highest CCT variation observed are defined. The obtained results have confirmed availability of the problem of variation of CCT of LED luminaires during their operation. Possible way of its resolution is application of more qualitative and therefore expensive LEDs with close proximity of phosphor or LEDs with remote phosphor. The article may be interesting both for manufacturers and consumers of LED light sources and lighting devices using them.


Heritage ◽  
2021 ◽  
Vol 4 (1) ◽  
pp. 188-197
Author(s):  
Dorukalp Durmus

Light causes damage when it is absorbed by sensitive artwork, such as oil paintings. However, light is needed to initiate vision and display artwork. The dilemma between visibility and damage, coupled with the inverse relationship between color quality and energy efficiency, poses a challenge for curators, conservators, and lighting designers in identifying optimal light sources. Multi-primary LEDs can provide great flexibility in terms of color quality, damage reduction, and energy efficiency for artwork illumination. However, there are no established metrics that quantify the output variability or highlight the trade-offs between different metrics. Here, various metrics related to museum lighting (damage, the color quality of paintings, illuminance, luminous efficacy of radiation) are analyzed using a voxelated 3-D volume. The continuous data in each dimension of the 3-D volume are converted to discrete data by identifying a significant minimum value (unit voxel). Resulting discretized 3-D volumes display the trade-offs between selected measures. It is possible to quantify the volume of the graph by summing unique voxels, which enables comparison of the performance of different light sources. The proposed representation model can be used for individual pigments or paintings with numerous pigments. The proposed method can be the foundation of a damage appearance model (DAM).


2021 ◽  
Vol 13 (12) ◽  
pp. 6880
Author(s):  
Mohammad Amdadul Haque ◽  
Siti Zaharah Sakimin ◽  
Phebe Ding ◽  
Noraini Md. Jaafar ◽  
Mohd Khanif Yusop ◽  
...  

In agricultural production, nitrogen loss leads to economic loss and is a high environmental risk affecting plant growth, yield, and quality. Use of the N fertilizer with a urease inhibitor is thus necessary to minimize N losses and increase the efficiency of N. This study aimed to evaluate the effects of N-(n-butyl) Thiophosphoric Triamide (NBPT) on the growth, yield, and quality of pineapple. The experiment involved two foliar fertilizer treatments: 1% (w/v) urea solution with NBPT (2.25 mL kg−1 urea) was treated as NLU (NBPT Liquid Urea), and the same concentration of urea without NBPT served as the control. Both were applied 12 times, starting 1 month after planting (MAP) and continuing once a month for 12 months. The application of urea with NBPT notably increased the above-ground dry biomass per plant (20% and 10% at 8 and 12 MAP, respectively), leaf area per plant (23% and 15% at 8 and 12 MAP, respectively), N accumulation per plant (10%), PFPN (Partial Factor Productivity) (13%), and average fruit weight (15%) compared to the treatment with urea alone (control). The analysis of quality parameters indicated that urea with NBPT improves TSS (Total Soluble Solids) (19%), ascorbic acid (10%), and sucrose (14%) but reduces the total organic acid content (21%) in pineapple. When using urea with a urease inhibitor (NBPT), there was a significant improvement in growth, yield, quality, and nitrogen use efficiency, with the additional benefit of reduced nitrogen losses, in combination with easy handling. Hence, urea with a urease inhibitor can be used as a viable alternative for increasing pineapple yield by boosting growth with better fruit quality.


2021 ◽  
Vol 2021 (29) ◽  
pp. 136-140
Author(s):  
Dorukalp Durmus

The quality of building electric lighting systems can be assessed using color rendition metrics. However, color rendition metrics are limited in quantifying tunable solid-state light sources, since tunable lighting systems can generate a vast number of different white light spectra, providing flexibility in terms of color quality and energy efficiency. Previous research suggests that color rendition is multi-dimensional in nature, and it cannot be simplified to a single number. Color shifts under a test light source in comparison to a reference illuminant, changes in color gamut, and color discrimination are important dimensions of the quality of electric light sources, which are not captured by a single-numbered metric. To address the challenges in color rendition characterization of modern solid-state light sources, the development of a multi-dimensional color rendition space is proposed. The proposed continuous measure can quantify the change in color rendition ability of tunable solid-state light devices with caveats. Future work, discretization of the continuous color rendition space, will be carried out to address the shortcomings of a continuous three-dimensional space.


2010 ◽  
Vol 28 (2) ◽  
pp. 222-226 ◽  
Author(s):  
Luis Eduardo C Antunes ◽  
Nara Cristina Ristow ◽  
Ana Cristina R Krolow ◽  
Sílvia Carpenedo ◽  
Carlos Reisser Júnior

The strawberry cultivation is an important economic activity in the Rio Grande do Sul State, Brazil, however the number of offered cultivars to the growers is reduced. The yield and quality of strawberry (Fragaria x ananassa Duch.) cultivars Camarosa, Galexia, Earlibrite, Festival, Plarionfre and Sabrosa was evaluated under the climatic conditions of Pelotas, Rio Grande do Sul State. We determined the number, mass, total soluble solids (TSS ºBrix), total titratable acidity (TTA), antocianin level and fresh fruits produced in an experimental unit. We also determined the production of fruits per hectare and per plant. The statistical design used in the experiment was of completely randomized blocks with 6 treatments (cultivars) and 4 replicates where the experimental unit was composed of 8 plants. The harvest began in the first half of August, extending to the second half of December, totalling 20 weeks. Plarionfre, Earlibrite and Festival cultivars showed higher production from the first half of October until the end of the first half of November. Camarosa reached higher productivity, mass of plants and fruit weight. There were no differences between the evaluated cultivars in the levels of TSS, antocianin, ATT and pH during the period of evaluation.


Agronomy ◽  
2018 ◽  
Vol 8 (10) ◽  
pp. 207 ◽  
Author(s):  
Hao Wei ◽  
Jiangtao Hu ◽  
Chen Liu ◽  
Mengzhao Wang ◽  
Jin Zhao ◽  
...  

Supplementary lighting is commonly used in high-quality seedling production. In this study, grafted tomato seedlings were grown for 10 days in a glasshouse with 16-h daily supplementary lighting at 100 μmol·m−2·s−1 PPFD (Photosynthetic photon flux density) from either high-pressure sodium (HPS), metal halide (MH), far-red (FR), white LEDs (Light emitting diodes) (W), or mixed LEDs (W1R2B1, where the subscript numbers indicate the ratio of the LED chips) to determine which light sources improve the seedling quality. The control seedlings did not receive any supplementary light. Physiological parameters and the expression of genes related to photosynthesis were analyzed. The results showed that root length, biomass, number of leaves, chlorophyll (SPAD), scion dry weight to height ratio (WHR), and specific leaf weight (SLW) were the greatest for grafted seedlings grown in W1R2B1. The level of root ball formation was the greatest for seedlings grown in W1R2B1, followed by those grown in W, HPS, and MH. Seedlings grown in FR did not fare well, as they were very thin and weak. Moreover, the expression of two photosynthetic genes (PsaA and PsbA) was significantly increased by W1R2B1 and W, which suggests that the plastid or nuclear genes might be regulated. The overall results suggest that W1R2B1 was the most suitable light source to enhance the quality of grafted tomato seedlings. The results of this study could be used as a reference for seedling production in glasshouses, and may provide new insights in the research on lights affecting the development of plants.


2019 ◽  
Vol 15 (2) ◽  
pp. 75
Author(s):  
Rafika Yuniawati ◽  
Siti Fatimah ◽  
Reni Indrayanti ◽  
Ifa Manzila ◽  
Tri Puji Priyatno ◽  
...  

<p>Red chili is a very important horticultural commodity in Indonesia having low productivity and quality. Cultivation method needs to be improved including the use of exogenous growth hormones. The purpose of this study was to determine (1) the optimum concentration of IAA and GA growing hormones from isolate B6.2 in stimulating plant growth and improving the quality of large red chili fruit; (2) molecular identity of the B6.2 bacterial isolate. The growth hormone content of B6.2 isolates using HPLC obtained 0.49 ppm IAA and 64.53 ppm GA. The growth hormone potential test on the growth and quality of chili was carried out with a concentration of 1, 3, 5 ml/l, while water and synthetic hormones was used as negative and positive control, respectively. The experimental design used was a Complete Random Design with the foliar spray application to the plant canopy three times during the growth period. The results showed the best concentration in increasing plant height, fruit weight, shooth wet, and dry weight compared to controls at the age of 76 days after planting (dap) was a concentration of 5 ml/l, with the values of 71.7±0.9 cm , 94.7±0.3 g, 11.5±0.43 g, and 1.4±0.09 g, respectively. The molecular identification showed that B6.2 isolate was classified as Bacillus vallismortis with 100% homology. The growth hormone from isolate B6.2 has the potential to increase growth and production of red chili plants.</p>


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