Special Issue "Role of Vertical Farming in Modern Horticultural Crop Production"

A special issue of Agronomy (ISSN 2073-4395). This special issue belongs to the section "Horticultural and Floricultural Crops".

Deadline for manuscript submissions: closed (30 September 2020).

Special Issue Editors

Prof. Dr. Jung Eek Son
Website
Guest Editor
Department of Plant Science, Seoul National University, Seoul 08826, Korea
Interests: protected horticulture; plant factory (vertical farm); soilless culture; crop growth modelling; electrical lighting; functional-structural plant modelling (FSPM); deep learning algorithm; spectrum conversion film; canopy photosynthesis; transpiration; nutrient management
Prof. Dr. Eiji Goto

Co-Guest Editor
Chiba Univ, Grad Sch Hort, 648 Matsudo, Matsudo, Chiba 2718510, Japan

Special Issue Information

Dear Colleagues,

Vertical farming is a technology of growing crops in many stacked layers under fully-controlled conditions using artificial lighting, which can produce high yield and high-quality crops through the year. Recently medicinal plants have been grown to obtain phytochemicals. Indoor farm, indoor vertical farm, and plant factory with artificial light (PFAL) are other terms used for describing vertical farm.

The world population is growing rapidly. The stable supply of high-quality, safe, and beneficial foods to humans is becoming important, and the production of high-value crops for economic improvement is also important. Recently, attention has been focused on vertical farms that meet these requirements.

However, vertical farming has advantages such as intensive crop production, planned production throughout the year, high-quality production, high-speed and mass production, and clean production and labor-saving production, regardless of time and space. On the other hand, it also has disadvantages, such as excessive costs for initial investment and maintenance, difficulties in managing nutrition solutions, and the need for high value-added crops to improve economics.

Therefore, we strongly need the knowledge and technologies necessary to establish relevant theories and industrialization. From the academic and industrial perspectives, the role of vertical farming is becoming more important as a next-generation plant production system. This is why we propose a Special Issue on the “Role of Vertical Farming in Modern Horticultural Crop Production.

Prof. Dr. Jung Eek Son
Prof. Dr. Eiji Goto
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All papers will be peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Agronomy is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 1600 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • Plant production
  • Vertical farm
  • Plant factory
  • Artificial lighting
  • Environmental control
  • Photosynthesis
  • Energy use efficiency
  • Phytochemicals
  • Medicinal plants
  • Nutrient solution
  • Light control
  • Smart technology

Published Papers (13 papers)

Order results
Result details
Select all
Export citation of selected articles as:

Research

Open AccessArticle
Indoor Farming Marjoram Production—Quality, Resource Efficiency, and Potential of Application
Agronomy 2020, 10(11), 1769; https://doi.org/10.3390/agronomy10111769 - 12 Nov 2020
Abstract
Indoor vertical farming offers great opportunities regarding a sustainable and consistent production of high-quality herbs and raw materials all year round for the perfume, chemical, or food industry. Cultivation takes place in an enclosed structure, operating predominantly independent from external conditions in multi-layer [...] Read more.
Indoor vertical farming offers great opportunities regarding a sustainable and consistent production of high-quality herbs and raw materials all year round for the perfume, chemical, or food industry. Cultivation takes place in an enclosed structure, operating predominantly independent from external conditions in multi-layer systems equipped with artificial lighting, enabling extremely high resource use efficiencies with a simultaneous increase in yield. On the other hand, field production in terms of plant quality and harvesting times is highly influenced by environmental conditions, making it difficult to maintain homogenous raw material qualities throughout the year. To show how different light qualities affect the overall efficiency and quality of Origanum majorana grown in an indoor farm, the resource consumption, yield, and cultivation time as well as the essential oil quantity was analyzed, and the efficiencies in terms of energy and land use efficiency calculated. The experimental setup clearly demonstrated that the yield regarding fresh as well as dry matter and oil content was comparable to one square meter of open field production. Based on this, the multi-layer system and the noticeable lowered growth period result in a significantly higher area efficiency compared to the open field, leading to a potential increase of annual yields of dried leave weight and oil contents by up to 21 times. It was also shown that a white spectrum (W) showed similar influence on plant growth and yield as a spectrum consisting of blue and red (B/R). Nevertheless, the LED treatment W did show higher light use efficiencies as well as a better working conditions inside the cultivation chamber. By an integration of indoor vertical farming into existing industrial processes, new and innovative opportunities for a flexible and low-risk supply chain seem feasible and according to German food industry meet the interests of existing stakeholders. Full article
(This article belongs to the Special Issue Role of Vertical Farming in Modern Horticultural Crop Production)
Show Figures

Graphical abstract

Open AccessArticle
Phenotypic Analysis of Germination Time of Individual Seeds Affected by Microenvironment and Management Factors for Cohort Research in Plant Factory
Agronomy 2020, 10(11), 1680; https://doi.org/10.3390/agronomy10111680 - 29 Oct 2020
Abstract
Plant phenotyping plays a crucial role in understanding variations in the phenotype of individual plants affected by environment, management, and genotype. Measurement of seed germination is an important phenotyping stage as germination impacts on the whole plant growth process. However, germination measurement has [...] Read more.
Plant phenotyping plays a crucial role in understanding variations in the phenotype of individual plants affected by environment, management, and genotype. Measurement of seed germination is an important phenotyping stage as germination impacts on the whole plant growth process. However, germination measurement has been limited to germination percentage of a seed population. Understanding of the germination time, from sowing to outbreak of the radicle from seed coat, at a single seed level is essential. How individual germination time and further plant growth are affected by its microenvironment and management factors remains elusive. Plant phenotype measurement system was developed to assess individual germination time of romaine lettuce (Lactuca sativa L. var. longifolia), using time-series two-dimensional camera images, and to analyze how microenvironment (volumetric water percent in seed tray, individual seed surface temperature and air temperature) and management factors (coated/uncoated seeds) affect the germination time for plant cohort research, emphasizing practicality in commercial cultivation. Germination experiments were conducted to demonstrate the performance of the system and its applicability for a whole plant growth process in a plant factory for commercial production and/or breeding. The developed phenotyping platform revealed the effects of microenvironment and management factors on germination time of individual seeds. Full article
(This article belongs to the Special Issue Role of Vertical Farming in Modern Horticultural Crop Production)
Show Figures

Figure 1

Open AccessArticle
Evaluation of the Light Environment of a Plant Factory with Artificial Light by Using an Optical Simulation
Agronomy 2020, 10(11), 1663; https://doi.org/10.3390/agronomy10111663 - 28 Oct 2020
Abstract
Good lighting designs can establish suitable light environments in plant factories with artificial light (PFALs). This study used optical simulations to investigate the effects of lighting designs in PFALs on the coefficient of variation of light absorption (Φp; CV) of individual [...] Read more.
Good lighting designs can establish suitable light environments in plant factories with artificial light (PFALs). This study used optical simulations to investigate the effects of lighting designs in PFALs on the coefficient of variation of light absorption (Φp; CV) of individual plants and the coefficient of utilization for the lighting system (U). Three-dimensional models of canola plants were constructed using a scanner, and a 3D model of the cultivation shelf was also created. The photosynthetic photon flux density (PPFD) distribution in the cultivation spaces, with or without the canola plants, was estimated first. The PPFD on the canola leaves was then estimated when the lighting design parameters, such as number, distance, height, radiant flux, and light distribution of the light-emitting diode lamps, were modified. The optical simulation showed good accuracy when estimating the PPFD distributions on the cultivation shelf and the leaves of the canola plants. The results showed that while the PPFD distribution across the growing area was uniform, it was not on a plant canopy. By appropriately controlling the layout of the lamps and their directionality, lighting designs that reduce Φp; CV and improve U in PFAL could be possible, and optical simulations could help to develop them. Full article
(This article belongs to the Special Issue Role of Vertical Farming in Modern Horticultural Crop Production)
Show Figures

Figure 1

Open AccessArticle
Increasing Growth of Lettuce and Mizuna under Sole-Source LED Lighting Using Longer Photoperiods with the Same Daily Light Integral
Agronomy 2020, 10(11), 1659; https://doi.org/10.3390/agronomy10111659 - 28 Oct 2020
Abstract
Light recommendations for horticultural crops often focus on the optimal daily light integral (DLI) without regard to how that light is delivered throughout each day. Because photosynthesis is more efficient at lower photosynthetic photon flux density (PPFD), we hypothesized that longer photoperiods with [...] Read more.
Light recommendations for horticultural crops often focus on the optimal daily light integral (DLI) without regard to how that light is delivered throughout each day. Because photosynthesis is more efficient at lower photosynthetic photon flux density (PPFD), we hypothesized that longer photoperiods with lower PPFD results in faster growth than shorter photoperiods with higher PPFD and the same DLI. We quantified the effect of different photoperiods, all providing the same DLI, on photosynthesis and growth of two leafy greens. Mizuna (Brassica rapa var. japonica) and lettuce (Lactuca sativa) “Little Gem” were grown from seed in a controlled environment chamber (20 °C and 819 µmol·mol−1 CO2) under six photoperiods (10, 12, 14, 16, 18, and 20 h). LED fixtures provided white light and PPFD was adjusted so each treatment received a DLI of 16 mol·m−2·d−1. Mizuna and lettuce were harvested 30 and 41 days after planting, respectively. Longer photoperiods with lower PPFD increased light interception, chlorophyll content index, quantum yield of photosystem II, and aboveground biomass, but decreased instantaneous CO2 assimilation of lettuce and mizuna. Aboveground biomass increased 16.0% in lettuce and 18.7% in mizuna in response to increasing the photoperiod from 10 to 20 h. In summary, extending the photoperiod and lowering PPFD increases growth of lettuce and mizuna by increasing light interception and the quantum yield of photosystem II. Full article
(This article belongs to the Special Issue Role of Vertical Farming in Modern Horticultural Crop Production)
Show Figures

Graphical abstract

Open AccessArticle
Response to Salt Stress in Lettuce: Changes in Chlorophyll Fluorescence Parameters, Phytochemical Contents, and Antioxidant Activities
Agronomy 2020, 10(11), 1627; https://doi.org/10.3390/agronomy10111627 - 22 Oct 2020
Abstract
Chlorophyll fluorescence (CF), growth parameters, phytochemical contents [proline, chlorophyll, ascorbic acid, total phenol content (TPC), total flavonoid content (TFC)], and antioxidant activities were investigated in lettuce (Lactuca sativa L.) seedlings grown under different sodium chloride (NaCl) concentrations (0, 50, 100, 200, 300, [...] Read more.
Chlorophyll fluorescence (CF), growth parameters, phytochemical contents [proline, chlorophyll, ascorbic acid, total phenol content (TPC), total flavonoid content (TFC)], and antioxidant activities were investigated in lettuce (Lactuca sativa L.) seedlings grown under different sodium chloride (NaCl) concentrations (0, 50, 100, 200, 300, and 400 mM) in a controlled environment for eight days. The parameters were evaluated at two days intervals. Almost of the CF and growth parameters as well as phytochemicals were significantly affected by both NaCl concentrations and progressive treatment schedule. The maximum quantum yield (Fv/Fm), effective quantum yield of photochemical energy conversion in PSII [Y(PSII)], coefficient of photochemical quenching (qP), coefficient of non-photochemical quenching (qN), and ratio of fluorescence decline (Rfd) showed decrements only at the highest saline concentration (400 mM), whereas the quantum yield of non-regulated energy dissipation in PSII [Y(NO)] exhibited a dissipation trend. All the growth parameters decreased with increasing NaCl concentrations, showing the highest decrease (~8 fold) in shoot fresh weight, compared to control seedlings. Proline significantly increased with increasing NaCl concentration and treatment time. Other phytochemicals decreased with the increase in NaCl concentration and reached their lowest at 400 mM. Overall, the results showed major changes in all parameters when the seedlings were grown at a NaCl concentration of 400 mM. The present findings will be useful for understanding the differential effect of NaCl concentrations in lettuce seedlings, and also might be useful to optimize the NaCl concentrations in other crops grown in controlled environmental conditions. Full article
(This article belongs to the Special Issue Role of Vertical Farming in Modern Horticultural Crop Production)
Show Figures

Figure 1

Open AccessArticle
Interpretation and Evaluation of Electrical Lighting in Plant Factories with Ray-Tracing Simulation and 3D Plant Modeling
Agronomy 2020, 10(10), 1545; https://doi.org/10.3390/agronomy10101545 - 11 Oct 2020
Abstract
In plant factories, light is fully controllable for crop production but involves a cost. For efficient lighting, light use efficiency (LUE) should be considered as part of light environment design. The objectives of this study were to evaluate and interpret the light interception, [...] Read more.
In plant factories, light is fully controllable for crop production but involves a cost. For efficient lighting, light use efficiency (LUE) should be considered as part of light environment design. The objectives of this study were to evaluate and interpret the light interception, photosynthetic rate, and LUE of lettuces under electrical lights using ray-tracing simulation. The crop architecture model was constructed by 3D scanning, and ray-tracing simulation was used to interpret light interception and photosynthesis. For evaluation of simulation reliability, measured light intensities and photosynthetic rates in a growth chamber were compared with those obtained by simulation at different planting densities. Under several scenarios modeling various factors affecting light environments, changes in light interception and LUE were interpreted. The light intensities and photosynthetic rates obtained by simulation showed good agreement with the measured values, with R2 > 0.86. With decreasing planting density, the light interception of the central plant increased by approximately 18.7%, but that of neighboring plants decreased by approximately 5.5%. Under the various scenarios, shorter lighting distances induced more heterogenetic light distribution on plants and caused lower light interception. Under a homogenous light distribution, the light intensity was optimal at approximately 360 μmol m−2 s−1 with an LUE of 6.5 g MJ−1. The results of this study can provide conceptual insights into the design of light environments in plant factories. Full article
(This article belongs to the Special Issue Role of Vertical Farming in Modern Horticultural Crop Production)
Show Figures

Figure 1

Open AccessArticle
Translation of Irrigation, Drainage, and Electrical Conductivity Data in a Soilless Culture System into Plant Growth Information for the Development of an Online Indicator Related to Plant Nutritional Aspects
Agronomy 2020, 10(9), 1306; https://doi.org/10.3390/agronomy10091306 - 02 Sep 2020
Abstract
Electrical conductivity of the growing media or drainage indicates the nutritional conditions in the cultivation system. However, the nutrient uptake phenomenon has not been related well to the soilless culture system. Herein, we report on the design, theoretical analyses, and verification of a [...] Read more.
Electrical conductivity of the growing media or drainage indicates the nutritional conditions in the cultivation system. However, the nutrient uptake phenomenon has not been related well to the soilless culture system. Herein, we report on the design, theoretical analyses, and verification of a method for an online indicator related to plant nutritional aspects. Models for simulating nutrient and water transport in a porous medium were constructed for analyses of the nutrient uptake estimation method. In simulation analyses, we summarized the theoretical relationships between flow rates of total nutrients in a substrate and nutrient uptake. For concept validation, we conducted a greenhouse experiment for correlation analysis with the growth of tomato plants, conventional nutrient, and water management indicators, and developed online indicators related to plant nutritional aspects. Onsite application of the indicator showed a higher correlation with tomato yield than conventional management indicators, such as transpiration, irrigation, drainage ratio, leaching fraction, and electrical conductivity of drainage. In addition, to assess the usability of a nutrient uptake indicator as an onsite decision-making technique, data normalization was conducted. Through this, the time series responsiveness of a nutrient uptake indicator to the yield change was confirmed. Full article
(This article belongs to the Special Issue Role of Vertical Farming in Modern Horticultural Crop Production)
Show Figures

Figure 1

Open AccessArticle
Growth, Nutritional Quality and Health-Promoting Compounds in Chinese Kale Grown under Different Ratios of Red:Blue LED Lights
Agronomy 2020, 10(9), 1248; https://doi.org/10.3390/agronomy10091248 - 25 Aug 2020
Abstract
Chinese kale (Brassica alboglabra Bailey) is one of the healthiest vegetables which is rich in health-promoting phytochemicals, including carotenoids, vitamin C, amino acid, glucosinolates, anthocyanin, flavonoids and phenolic compounds. The effects of different LEDs (white LED, 8R1B (red:blue = 8:1), 6R3B (red:blue [...] Read more.
Chinese kale (Brassica alboglabra Bailey) is one of the healthiest vegetables which is rich in health-promoting phytochemicals, including carotenoids, vitamin C, amino acid, glucosinolates, anthocyanin, flavonoids and phenolic compounds. The effects of different LEDs (white LED, 8R1B (red:blue = 8:1), 6R3B (red:blue = 6:3)) on nutritional quality in flower stalks and leaves of Chinese kale were investigated in this study. 8R1B and 6R3B were more effective than white LED light for improvement of growth and quality of Chinese kale. Flower stalk contained a higher content of nutritional compounds than leaves in Chinese kale. 8R1B significantly promoted plant growth, accumulation of biomass and soluble sugar content in flower stalks. In contrast, 6R3B significantly reduced plant dry matter, but it promoted nutritional compounds accumulation in flower stalks, such as soluble proteins, total glucosinolate, total anthocyanin, flavonoid, antioxidant activity. In addition, 6R3B enable to increase the amount of sourness and umami tasty amino acids, as well as precursor amino acids of glucosinolate. Accumulation balance of biomass and nutritional compounds is related to the ratio of red to blue light. Generally, 6R3B was more conducive to the enrichment of health-promoting compounds, as well as umami in Chinese kale. Full article
(This article belongs to the Special Issue Role of Vertical Farming in Modern Horticultural Crop Production)
Show Figures

Figure 1

Open AccessArticle
Effects of Daily Light Integral and LED Spectrum on Growth and Nutritional Quality of Hydroponic Spinach
Agronomy 2020, 10(8), 1082; https://doi.org/10.3390/agronomy10081082 - 27 Jul 2020
Cited by 2
Abstract
To achieve clean and high-quality spinach production, the effects of daily light integral (DLI) and light spectrum on growth, nutritional quality, and energy yield of hydroponic spinach (Spinacia oleracea L.) were investigated in a closed plant factory under light-emitting diode (LED) lighting. [...] Read more.
To achieve clean and high-quality spinach production, the effects of daily light integral (DLI) and light spectrum on growth, nutritional quality, and energy yield of hydroponic spinach (Spinacia oleracea L.) were investigated in a closed plant factory under light-emitting diode (LED) lighting. The hydroponic spinach plants were grown under 16 combinations of four levels of DLI (11.5, 14.4, 17.3, and 20.2 mol m−2 day−1) with four light spectra: LED lamps with ratio of red light to blue light (R:B ratio) of 0.9, 1.2, and 2.2 and fluorescent lamps with R:B ratio of 1.8 as control. The results show that total fresh and dry weights, energy yield, and light energy use efficiency (LUE) of harvested spinach were higher under D17.3-L1.2 treatment compared to other treatments. The higher net photosynthetic rates were shown at DLI of 17.3 mol m−2 day−1 regardless of light quality. Higher vitamin C contents of spinach in all LED treatments were obtained compared with the control. L1.2 treatments with higher fraction of blue light led to more vitamin C content, lower nitrate content, and higher LUE independent of DLI. L2.2 treatment with more fraction of red light was beneficial to reduce oxalate accumulation. Power consumption based on increased total fresh weight under LED lamps with R:B ratio of 1.2 in different DLIs was over 38% lower than that under the fluorescent lamps and 1.73 kWh per 100 g FW at DLI of 17.3 mol m−2 day−1. In conclusion, lighting environment in DLI of 17.3 mol m−2 day−1 using LED lamps with R:B ratio of 1.2 is suggested for the design of a LED plant factory for hydroponic spinach production. Full article
(This article belongs to the Special Issue Role of Vertical Farming in Modern Horticultural Crop Production)
Show Figures

Figure 1

Open AccessArticle
Growth and Acclimation of In Vitro-Propagated M9 Apple Rootstock Plantlets under Various Visible Light Spectrums
Agronomy 2020, 10(7), 1017; https://doi.org/10.3390/agronomy10071017 - 15 Jul 2020
Abstract
This study aimed to explore the suitable light quality condition for ex vitro acclimation of M9 apple plantlets. Light quality treatments were set as followed; monochromatic LEDs (red (R), green (G), blue (B)) and polychromatic LEDs (R:B = 7:3, 8:2 and 9:1; R:G:B [...] Read more.
This study aimed to explore the suitable light quality condition for ex vitro acclimation of M9 apple plantlets. Light quality treatments were set as followed; monochromatic LEDs (red (R), green (G), blue (B)) and polychromatic LEDs (R:B = 7:3, 8:2 and 9:1; R:G:B = 6:1:3, 7:1:2 and 8:1:1). Plant height of R, R9B1, and R8G1B1 treatments were significantly higher than the other treatments. The number of leaves and SPAD value of B were significantly higher than the other treatments. Root fresh weights of R9B1 and R7G1B2 treatments showed an increase of at least 1.7-times compared to R, G and R8B2. R8G1B1 accumulated higher starch contents than the other treatments. Photosynthetic rate of R9B1 and R8B2 were significantly higher than the other treatments. In terms of stomatal conductance and transpiration rate, treatments with high blue ratio such as B, R7B3 had higher values. Rubisco concentration was high in R and B among monochromatic treatments. In conclusion, red light was effective to increase photosynthetic rate and biomass and blue light increased chlorophyll content and stomatal conductance. Therefore, for R9B1 and R8G1B1, a mixture of high ratio of red light with a little blue light would be proper for the acclimation of in vitro-propagated apple rootstock M9 plantlets to an ex vitro environment. Full article
(This article belongs to the Special Issue Role of Vertical Farming in Modern Horticultural Crop Production)
Show Figures

Figure 1

Open AccessArticle
Effects of Photoperiod Interacted with Nutrient Solution Concentration on Nutritional Quality and Antioxidant and Mineral Content in Lettuce
Agronomy 2020, 10(7), 920; https://doi.org/10.3390/agronomy10070920 - 27 Jun 2020
Cited by 1
Abstract
The interacted effects of photoperiod and nutrient solution concentrations (NSCs) on nutritional quality and antioxidant and mineral content in lettuce were investigated in this study. There were a total of nine treatments by three photoperiods (12 h/12 h, 15 h/9 h, and 18 [...] Read more.
The interacted effects of photoperiod and nutrient solution concentrations (NSCs) on nutritional quality and antioxidant and mineral content in lettuce were investigated in this study. There were a total of nine treatments by three photoperiods (12 h/12 h, 15 h/9 h, and 18 h/6 h), with a combination of three NSCs (1/4, 1/2, and 3/4 NSC). The contents of photosynthetic pigment, mineral element, and nutritional quality were markedly affected by the combination of photoperiod and NSC. The highest leaf number and plant weight were found in lettuce under the combination of 18–0.25X. There was a higher content of photosynthetic pigment in treatment of 15-0.25X. Shorter photoperiod (12 h/12 h and 15 h/9 h) and NSC (1/4 and 1/2 NSC) contributed to reduced nitrate contents and higher contents of free amino acid, soluble protein, and vitamin C. Longer photoperiod and lower NSC could increase soluble sugar content. The content of total P, K, and Ca exhibited a similar trend under the combination of photoperiod and NSC, with a higher content at 3/4 NSC under different photoperiods. Lower contents of total Zn and N were found under longer photoperiod. Moreover, higher antioxidant contents, including 2, 2-diphenyl-1-picrylhydrazyl (DPPH), value of ferric-reducing antioxidant power (FRAP), flavonoid, polyphenol, and anthocyanin were observed under shorter photoperiod, with the peak under 12-0.50X. Generally, 12-0.50X might be the optimal treatment for the improvement of the nutritional quality of lettuce in a plant factory that produced high-quality vegetables. Full article
(This article belongs to the Special Issue Role of Vertical Farming in Modern Horticultural Crop Production)
Show Figures

Figure 1

Open AccessArticle
Resource Utilization Efficiencies in a Closed System with Artificial Lighting during Continuous Lettuce Production
Agronomy 2020, 10(5), 723; https://doi.org/10.3390/agronomy10050723 - 18 May 2020
Cited by 2
Abstract
New plant production systems with a low environmental impact (or a high resource utilization efficiency) are necessary for urban agriculture development. This study explores the benefits of closed plant production systems (CPPSs) with artificial lighting using a commercial CPPS at Osaka Prefecture University. [...] Read more.
New plant production systems with a low environmental impact (or a high resource utilization efficiency) are necessary for urban agriculture development. This study explores the benefits of closed plant production systems (CPPSs) with artificial lighting using a commercial CPPS at Osaka Prefecture University. Lettuce plants were produced continuously as a model for analyzing resource consumption rates, such as electricity, labor, water, and CO2, over two years. Monthly consumption rates of electricity, labor, water, and CO2 increased with the increase in the monthly production rate of the lettuce. The utilization efficiencies (=output/input) of electricity, energy, water, and CO2 were 1.0%, 1.0%, 4.0%, and 32.6%, respectively. If the commercial CPPS maintains the monthly production rate at a higher level, the energy utilization efficiency will increase. The number of air exchanges in a commercial CPPS should decrease to increase water and CO2 utilization efficiencies. Reusing water drained from the air conditioning system and employing a closed loop in the nutrient supply system also contribute to increasing the water utilization efficiency and lowering the environmental impact. Although a commercial CPPS still requires further improvements, it may be a good crop production system for urban agriculture provided resource utilization efficiencies improve. Full article
(This article belongs to the Special Issue Role of Vertical Farming in Modern Horticultural Crop Production)
Show Figures

Figure 1

Open AccessArticle
Estimation of the Constituent Properties of Red Delicious Apples Using a Hybrid of Artificial Neural Networks and Artificial Bee Colony Algorithm
Agronomy 2020, 10(2), 267; https://doi.org/10.3390/agronomy10020267 - 13 Feb 2020
Cited by 2
Abstract
Non-destructive estimation of the constituent properties of fruits and vegetables has led to a dramatic change in the agriculture and food industry, allowing accurate and efficient sorting of the products based on their internal properties. Therefore, the present study utilized visible (VIS) and [...] Read more.
Non-destructive estimation of the constituent properties of fruits and vegetables has led to a dramatic change in the agriculture and food industry, allowing accurate and efficient sorting of the products based on their internal properties. Therefore, the present study utilized visible (VIS) and near-infrared (NIR) spectroscopy data in the range from 200 to 1100 nm for the estimation of several properties of Red Delicious apples, namely Brix minus acid (BrimA), firmness, acidity and starch content, using a hybrid of Artificial Neural Networks and Artificial Bee Colony (ANN–ABC) algorithm. Furthermore, the hybrid Artificial Neural Network–Particle Swarm Optimization (ANN–PSO) algorithm was utilized to select the most effective properties to estimate these characteristics. The results indicated that there are different peaks within this spectral range, and the spectral range for each peak gives different results. To ensure the stability of the proposed method, 1000 replications were performed for each estimate. The highest coefficients of determination, R2, for estimating the studied properties among the 1000 replicates were 0.898 for BrimA, 0.8 for firmness, 0.825 for acidity and 0.973 for starch content. The selection of the most effective wavelengths for estimating the properties produced five effective wavelengths for BrimA, nine for firmness, seven for acidity and five for starch content. In this case, the best R2 of the hybrid ANN–ABC among the 1000 iterations were 0.828, 0.738, 0.9 and 0.923, respectively. Full article
(This article belongs to the Special Issue Role of Vertical Farming in Modern Horticultural Crop Production)
Show Figures

Figure 1

Back to TopTop