Nutrient Solution Temperature Research Articles

Comparative efficacy of non-electric cooling techniques to reduce nutrient solution temperature for the sustainable cultivation of summer vegetables in open-air hydroponics.

The cultivation of summer vegetables in open-air nutrient film technique (NFT) hydroponics is limited due to the elevated nutrient solution temperature (NST). In this regard, non-electric evaporative-cooling techniques were explored to maintain NST in open-air NFT hydroponics. Four cooling setups were employed by wrapping polyvinyl chloride (PVC) grow pipes with one and two layers of either wet or dry jute fabrics and attaching them with coiled aluminum pipe buried inside a) wet sand-filled brick tunnels (Cooling Setup I), b) two inverted and vertically stacked earthen pots (Cooling Setup II), c) two inverted and vertically stacked earthen pots externally wrapped with wet jute fabric (Wrapped Cooling Setup II), and d) an earthen pitcher wrapped with wet jute fabric (Cooling Setup III). Wrapping grow pipes with two layers of wet jute fabric reduced NST by 5°C as compared to exposed (naked) grow pipes. The double-layer jute fabric-wrapped grow pipes produced 182% more reduction in NST in comparison to single layer-wrapped grow pipes. Additionally, the installation of Wrapped Cooling Setup II and Cooling Setup III outperformed Cooling Setup I and Cooling Setup II through NST reduction of approximately 4°C in comparison to control. Interestingly, Cooling Setup III showed its effectiveness through NST reductions of 193%, 88%, and 23% during 11a.m.-12 p.m. as compared to Cooling Setup I, Cooling Setup II, and Wrapped Cooling Setup II, respectively. In contrast, Wrapped Cooling Setup II caused NST reductions of 168%, 191%, and 18% during 2-3 p.m. in comparison to Cooling Setup I, Cooling Setup II, and Cooling Setup III, respectively. Thus, the double-layer jute fabric-wrapped grow pipes linked with Wrapped Cooling Setup II can ensure summer vegetable cultivation in open-air NFT hydroponics as indicated by the survival of five out of 12 vegetable plants till harvest by maintaining NST between 26°C and 28°C.

Hydroponic Nutrient Solution Temperature Impacts Tulane Virus Persistence over Time

Controlled environment agriculture (CEA), or indoor agriculture, encompasses non-traditional farming methods that occur inside climate-controlled structures (e.g., greenhouses, warehouses, high tunnels) allowing for year-round production of fresh produce such as leaf lettuce. However, recent outbreaks and recalls associated with hydroponically grown lettuce contaminated with human pathogens have raised concerns. Few studies exist on the food safety risks during hydroponic cultivation of leaf lettuce; thus, it is important to identify contributing risk factors and potential mitigation strategies to prevent foodborne transmission via hydroponically grown produce. In this study, the concentration of infectious Tulane virus (TV), a human norovirus surrogate, in hydroponic nutrient solution at 15 °C, 25 °C, 30 °C, and 37 °C was determined over a duration of 21 days to mimic the time from seedling to mature lettuce. The mean log PFU reduction for TV was 0.86, 1.80, 2.87, and ≥ 3.77 log10 at 15 °C, 25 °C, 30 °C, and 37 °C, respectively, at the end of the 21-day period. Similarly, average decimal reduction values (D-values) of TV at 15 °C, 25 °C, 30 °C, and 37 °C were 48.0, 11.3, 8.57, and 7.02 days, respectively. This study aids in the (i) identification of possible food safety risks associated with hydroponic systems specifically related to nutrient solution temperature and (ii) generation of data to perform risk assessments within CEA leaf lettuce operations to inform risk management strategies for the reduction of foodborne outbreaks, fresh produce recalls, and economic losses.

An optimization approach for environmental control using quantum genetic algorithm and support vector regression

Photosynthesis serves as the foundation for vegetable crop yield. It is crucial to appropriately regulate the environmental parameters associated with photosynthesis to ensure efficient production and energy conservation in plant factories or greenhouses. In this research, we proposed a novel optimization approach for determining the target value of environmental control, aiming to balance plant growth and energy cost. By employing hydroponic lettuces as experimental samples, we measured their photosynthetic rates (Pn) under various combinations of four environmental factors: air temperature (AT), nutrient solution temperature (NST), photon flux density (PFD), and CO2 concentration ([CO2]). The photosynthetic data were combined with the support vector regression algorithm to develop a Pn prediction model. This model achieved a coefficient of determination of 0.9748, a root mean square error value of 0.9302 µmol∙m−2∙s−1, and a mean absolute error value of 1.1813 µmol∙m−2∙s−1. The model provide data for subsequent environmental control. The quantum genetic algorithm (QGA) was employed to search the optimal Pn and corresponding PFD, [CO2], and NST at different ATs. The fitness function for QGA was developed considering both the Pn and the energy consumption. This approach could calculate the target environments (PFD, [CO2], and NST) for any given AT. Compared with the Pn maximization approach, the energy cost-saving rate was 1.5 to 3.5 times higher than the Pn loss. The proposed approach could quickly and accurately determine an optimal environmental control target value, outperforming other approaches in complexity and generality. Thus, this study offers an elegant approach to environmental control for hydroponic cultivation.

Development of a multi-node monitoring system for analyzing plant growth and indoor environment interactions: An empirical study on a plant factory

In plant factories, multi-layered shelves are used to maximize production per unit area by densely growing plants. The large number of plants placed in a spacious area leads to complex interactions between the plants and the growing environment, resulting in a potentially non-uniform growing environment. When the environment is non-uniform, achieving consistent production based on location becomes challenging. This study aims to analyze these interactions through multi-node, multi-factor monitoring in an actual plant factory that engages in hydroponics. To achieve this, we developed a monitoring system tailored for measuring the growth environment in plant factories. Specifically, we created a monitoring device capable of real-time measurement of six key indoor environmental factors, a network system that facilitates multi-node data collection by utilizing both Zigbee and WiFi, and a dashboard for simplified management. The developed monitoring system was implemented in an 'A' plant factory and collected 44,640 data points over a month. It empirically demonstrated that indoor environmental factors vary by location within the growing space, depending on the surrounding environment and the placement and operation of environmental facilities. The temperature of the nutrient solution showed a statistically strong correlation with other indoor environmental factors. This indicates that the operation of environmental facilities in a plant factory should be comprehensively managed in real-time, with a focus on the relationship of the nutrient solution temperature to other indoor environmental factors. Such management is especially crucial when considering the dynamic interrelationships among nutrient solution temperature, other indoor conditions, and the varying demands imposed by plant growth activity. These results offer valuable guidelines for optimizing the growing environment in plant factories and will serve as an important reference for plant factory operators.

Relationships of Water Quality Parameters for Hydroponic Production of Kale (Brassica oleracea) with In-Ground Passive Cooling System

Greenhouses in Philippines are encountering high ambient air temperature problem. Along with this, the water quality directly affects the growth, development and yield of hydroponically grown plants. This study was conceptualized through the principle of cooling the nutrient solution that will effectively regulate plant’s growth and yield with relatively low investment and easier management. One of the essential elements of a functional hydroponics system is water quality monitoring, hence this study utilized a monitoring system for water quality parameters. Nutrient solution was closely monitored to maintain and ensure that nutrient levels are not too low to inhibit growth and not too high to be potentially toxic. The study was conducted to develop a monitoring system for environmental and water quality parameters of in-ground passive cooling system for hydroponic production of kale. Specifically, the study aimed to determine the relationships of water quality parameters such as pH, EC, TDS, and temperature for kale production, compare the performance of an in-ground passive cooling system (IGPCS) and without cooling system (Control) on hydroponically grown kale, and to evaluate the water productivity of the in-ground passive cooling system. This study utilized both in-ground passive cooling system (IGPCS) and control (without cooling system) to compare its performance based on the growth and yield of the kale, and to determine the water productivity of utilizing IGPCS. In addition, water quality parameter such as pH, EC, TDS, and temperature were closely monitored using the installed monitoring system, and relationships of these water quality parameters were established. The gathered data were analyzed using trend analysis in Microsoft Excel, Analysis of variance (ANOVA) was computed in Completely Randomized Design (CRD) and comparison among means were compared using Least Significant Difference (LSD) Test at 5% level. Results revealed that EC and TDS of nutrient solution are inversely proportional to pH and temperature of nutrient solution, moreover EC and TDS are directly proportional, also with pH and temperature of nutrient solution. The performance of the IGPCS and without cooling system is comparable with growth and yield of kale in terms of leaf length, leaf width, number of leaves, weight and yield at harvest, but are significantly affected by the location of growing pipes where crops received less and ample amount of sunlight. Since the temperature of IGPCS was reduced up to 3°C, kale plants with cooling system uptake less water compared to without cooling system and results to higher productivity. Therefore, regulating one of the water quality parameters directly affects other water quality parameters, so relationships of these water quality parameters were established through close monitoring of water quality parameters using the monitoring system. Utilization of IGPCS reduced the temperature of the nutrient solution up to 3°C which gave higher yield (44.01 g/plant) than without cooling system (41.18 g/plant). Kale production in tropical areas can have higher yield using the in-ground passive cooling system that reduced water consumption, resulting to higher productivity.

Persistence of Salmonella enterica subsp. enterica ser. Javiana, Listeria monocytogenes, and Listeria innocua in Hydroponic Nutrient Solution

This study aimed to determine the persistence of Salmonella Javiana, Listeria monocytogenes, and Listeria innocua in nonsterile, hydroponic nutrient solution (NS) at 15, 25, 30, and 37°C over a 21-day period to mimic time from seedling to mature lettuce. Bacteria were inoculated in modified Hoagland's NS at 106 CFU/mL and maintained at 15, 25, 30, and 37°C. Samples were collected at various time points, and bacteria were quantified. A mixed model was used to determine the effect of bacteria type, time (day), and temperature on bacteria concentration (log CFU/mL). The least-squares means were calculated to compare the mean log CFU/mL, and the mean values were compared with Tukey-Kramer honest significant difference test with a significance level of P = 0.05. Statistical analysis indicated that a 3-way interaction effect between temperature, time, and bacteria type had a significant impact on bacterial persistence in NS (P < 0.0001). At all temperatures, S. Javiana persisted in NS throughout the 21-day study period, compared to L. innocua and L. monocytogenes where persistence was limited to between 1 and 14 days. Similarly, decimal reduction values (D-values) of S. Javiana indicated longer persistence in NS than L. innocua and L. monocytogenes at most temperatures. For instance, at 15°C and 25°C, D-values for S. Javiana were estimated at 82 and 26 d, respectively, compared to D-values of 3.6 and ∼3 d for L. monocytogenes. Data indicate that the temperature of NS has a differential effect on the persistence of S. Javiana and Listeria spp. This study furthers the understanding of potential food safety risks associated with hydroponic systems and will contribute to the refinement of further studies to aid in the development of operation-specific risk profiles.

Dense planting and environmental control (temperature, light intensity, and concentration of nutrient solution) can increase the yield of ginseng (Panax ginseng C. A. Meyer) seedlings in indoor cultivation with artificial light

Dense planting and environmental control (temperature, light intensity, and concentration of nutrient solution) can increase the yield of ginseng (Panax ginseng C. A. Meyer) seedlings in indoor cultivation with artificial light

Effect of Nutrient Solution Cooling in Summer and Heating in Winter on the Performance of Baby Leafy Vegetables in Deep-Water Hydroponic Systems

Hydroponics has become a popular production technology for leafy greens in greenhouses. However, year-round production of cool-season leafy greens remains challenging due to costly heating and cooling during winter and summer seasons, depending on location. Therefore, the objective of this study is to investigate the effect of nutrient solution cooling and heating in deep-water hydroponic systems on the performance of several leafy green vegetables. Two experiments of nutrient solution cooling during the summer season and another two experiments of nutrient solution heating during the winter season were conducted in Texas, USA in 2020–2021. Lettuce (Lactuca sativa L.) ‘Bergams Green’ and ‘Red Mist’, Pak Choi (Brassica rapa subsp. chinensis) ‘Purple Magic’ and ‘White Stem’, and spinach (Spinacia oleracea L.) ‘Mandolin’ and ‘Seaside’ were grown in the summer experiments, and only the two lettuce cultivars were grown for the winter experiments. For both cooling and heating studies, six deep-water culture systems were used with two treatments: cooling (23 °C) vs. no cooling, and heating (22 °C) vs. no heating, with three replications in each experiment. In the nutrient solution cooling study, spinach was the most heat-sensitive species, and ‘Mandolin’ was more heat-tolerant than ‘Seaside,’ as evidenced by its lower mortality rate in both experiments. Lettuce and pak choi grew well and solution cooling increased shoot fresh weight in both lettuce cultivars and in ‘White Stem’ pak choi but not in ‘Purple Magic’ pak choi. Conversely, during the winter season, solution heating increased shoot fresh weight of both lettuce cultivars; however, ‘Red Mist’ was more responsive than ‘Bergams Green’ lettuce. These results indicate the potential to increase crop yield by controlling nutrient solution temperature throughout the year, depending on the season. Also, there were genotypic differences in both cooling and heating experiments, indicating that more research is needed to determine the species-dependent and even cultivar-dependent nutrient solution temperature control strategies to achieve optimum year-round production.

The Acquisition and Analysis of Optimal Nutrient Solution Temperature Range for Lettuce Using U-Chord Curvature

The Acquisition and Analysis of Optimal Nutrient Solution Temperature Range for Lettuce Using U-Chord Curvature

Nutrient Solution Temperature Affects Growth and °Brix Parameters of Seventeen Lettuce Cultivars Grown in an NFT Hydroponic System

Nutrient solution temperature in a hydroponic system affects °Brix and yield of lettuce; thus, it is important to maintain the water temperature within an appropriate range. Nutrient-film technique (NFT) trials were conducted to investigate the effects of different water temperatures (18.3 °C, 21.1 °C, and ambient) on growth and °Brix of 17 cultivars from five different types (Loose leaf, Romaine, Butterhead, Salanova, and Batavian) of lettuce. The average daily water temperature for ambient treatment was recorded to be 20 to 26.5 °C. The study was conducted in a split-plot design with three replications over time. Results indicated that water temperature affected root and shoot fresh and dry weight, plant width, and °Brix for lettuce. Lettuce grown at 21.1 °C were 15% greater for shoot fresh weight than plants grown at ambient conditions. All the growth and quality parameters of lettuce were found to be affected by cultivars, with “Coastal Star” showing the best results in both growth and °Brix parameters. All the cultivars of the Romaine type showed greater growth and °Brix, while Salanova lettuce did not perform well in all treatments compared to other lettuce types. For CO2 assimilation, the interaction between water temperature and cultivars was significant, with “Parris Island” having the greatest rate at ambient water temperature. These results suggested that maintaining water temperature at 21.1 °C produced lettuce with greater growth and biomass but had 26% lower °Brix than lettuce grown at 18.3 °C.

ARM Based Smart Water Meter with LoRa for Soilless Agriculture Application

The aim of this study is to develop an integrated and micro-controller based electronic circuit which might be used in soilless agriculture and smart greenhouse systems. In this study, a novel soilless agriculture system design is proposed to measure and monitor parameters such as the desired ambient temperature, nutrient solution temperature, solution alkalinity (pH) and conductivity in the greenhouse. In addition to the design, a control mechanism is designed to keep the amount of nutrient solution, which changes over time, stable in the desired ranges. This proposed system consists of two different embedded systems where the necessary parameters are measured, actuators are controlled, and the related input / output pairs are observed. The yield of the nutrient solution in the system is continuously controlled, and the necessary conditions are provided for the growth of the product in the greenhouse. The microcontroller system is responsible for data transmission in the greenhouse, observing the pipes, and to identify possible problems which might be encountered in the corresponding lines. In addition, the embedded system in the field performs the control tasks of the actuators which takes a role in maintaining the temperature inside the greenhouse taking into account the feedback data. LoRa communication is employed to construct a data flow network between embedded systems. For this purpose, a new communication protocol is proposed to be used in soilless agriculture applications. In order to enable the users to observe the whole system in multi-greenhouse systems, a control unit (computer) is positioned over a main greenhouse where the relevant inputs / outputs of the embedded system can be read. The sensor and actuator data are obtained during the studies, the necessary conditions for soilless agriculture are examined, and the results are presented.

HYDROPONIC CULTIVATION OF CORIANDER USING FRESH AND BRACKISH WATERS WITH DIFFERENT TEMPERATURES OF THE NUTRIENT SOLUTION

A large number of studies on salinity in hydroponic systems have been carried out, but few of them have evaluated the interaction between salinity and nutrient solution temperatures. Two experiments were carried out in a randomized block design from January to February (Experiment I) and June to July 2018 (Experiment II). Experiment I consisted of treatments with five combinations, as follows: unheated (control) and heated nutrient solution (NS) at a temperature of 32°C using fresh water with an electrical conductivity (ECw) of 0.3 dS m−1, and unheated and heated NS at temperatures of 30 and 32°C using brackish water with an ECw of 6.5 dS m−1 in the main plots, with two coriander cultivars (Tabocas and Verdão) in the subplots, which were grown in the same hydroponic channel. The cultivar Verdão was grown in Experiment II in a 2 × 2 factorial arrangement, consisting of two NS temperatures (unheated and heated at 30°C) and two ECw levels (0.3 and 6.5 dS m−1). Coriander cultivation is feasible with heated NS despite decreases in shoot fresh matter production compared to the control of approximately 37% for Experiment I (cultivar Verdão at a temperature of 32°C and using fresh water) and 17% for Experiment II (temperature of 30°C and using fresh and brackish waters) at 25 days after transplanting.

Performance of Long Short-Term Memory Networks for Modeling the Response of Plant Growth to Nutrient Solution Temperature in Hydroponic

This study examines the development of an approach for modeling the response of plant growth to nutrient solution temperature in hydroponic cultivation in a dynamic system. Nutrient solution temperature is one of the essential manipulating factors for plant growth in hydroponic cultivation. Determining the optimal control strategy of nutrient solution temperature during cultivation could lead to maximize the growth of the plant. By identifying the process using a dynamic system, the optimal control strategy can be determined. However, developing a dynamic model of plant growth to nutrient solution temperature is not easy due to physiological behavior between them are quite complex and uncertain. We propose the long short-term memory (LSTM) networks to identify and develop a model of dynamic characteristics of plant growth as affected by the nutrient solution temperature. Chili pepper plants were used to obtain time-series data of plant growth, with five different types of dynamic nutrient solution temperature patterns for system identification. The results showed that the proposed LSTM model provides promising performance in predicting the response of plant growth to nutrient solution temperature in hydroponic cultivation.

Development of a Control System for Lettuce Cultivation in Floating Raft Hydroponics

Developing a control system for hydroponics is gaining high attention because of the possibility to increase resource efficiency in producing high quality vegetables. Applying such a control system for nutrient solution in hydroponics requires less labour and operational cost. Therefore, it is important to develop a control system for nutrient solution in hydroponics. This research was aimed to develop a control system for lettuce cultivation in floating raft hydroponics. The control system has been developed to control temperature, EC, pH, DO, and ORP of nutrient solution in the controlled floating raft hydroponics by using Arduino Mega 2560 microcontroller as a control unit and micro SD card as storage media. The control system was found to be able to maintain the temperature of nutrient solution in the range of 20 to 25°C, EC in the range of 1500 to 1700 μS/cm, pH in the range of 5.5 to 6.2, DO in the range of 4 to 8 ppm, and ORP in the range of 300 to 500 mV. The control system performed well in maintaining these parameters as showed by a better lettuce growth in the controlled floating raft hydroponics, as compared to that of without the control system.

Effects of Concentration and Temperature of Nutrient Solution on Growth and Camptothecin Accumulation of Ophiorrhiza pumila.

The medicinal plant, Ophiorrhiza pumila, naturally grows on the floors of humid inland forests in subtropical areas. It accumulates camptothecin (CPT), which is used as an anti-tumor agent, in all organs. We investigated the optimal hydroponic root-zone environments for growth and CPT accumulation in O. pumila in a plant factory. In experiment 1, to determine the appropriate nutrient solution concentration (NSC), O. pumila was cultivated using four concentrations (0.125, 0.25, 0.5, and 1.0 times) of a commercial solution for 63 days after the start of treatment (DAT). The electrical conductivity of these NSCs was 0.6, 0.9, 1.5, and 2.7 dS m−1, respectively. The total dry weights at 0.25 and 0.5 NSCs were higher than those at the other two NSCs. CPT content at 0.25 NSC was significantly higher than those at other NSCs. In experiment 2, to investigate an appropriate nutrient solution temperature (NST), O. pumila was cultivated at four NSTs (10, 20, 26, and 35 °C, named as T10, T20, T26, and T36, respectively) for 35 DAT. The growth and CPT content at T20 was the highest among the treatments. Therefore, root-zone environments of 0.25 NSC and 20 °C of NST produced the best growth and CPT accumulation in O. pumila.

Bottom-cold stress was less harmful than cold-air stress on tomato seedling production treated with boric acid

Boron is beneficial element can help plants face chilling stress. This research was arranged using factorial experiment based on randomized complete block design on Lycopersicon esculentum var. Infinity in Isfahan University of Technology due to having a new idea about bottom-cold and cold-air stress tomato seedling with boron application. There were two treatments having different boron (B1) concentrations (B1) 50.5 mM, and (B2) 75.82 mM. Three temperature treatment used as following: (1) the cold treatment used with vegetation chambers with low temperature (10 °C) (cold air), (2) the low nutrient solution (10 °C) temperature but the aerial part exposed to optimum temperature (bottom-cold) and (3) the last part, was the control plant (opt) keep in optimum root and shoot temperature (22 °C). Some physiological and biochemical characteristics were measured. The results were shown that boron uptake decreased in cold or stress as well as the water status of the plant which is suffering from cold-air stress greater than bottom-cold. Boron application, especially in higher concentration, improved some deleterious effect of cold stress, especially in the bottom-cold. The reason may refer to keeping photosynthesis traits in better level with B application. Cold-air stress, increased stress indices such as antioxidant and proline as well as glucose level and saturated/unsaturated fatty acid greater than bottom-cold stress. It was concluded that tomato was more resistant to bottom-cold stress than cold-air stress. Boron application increased the boron of leaves more effectively in the bottom-cold consequently increase plant tolerance to a chilling condition at the bottom-cold too.

Growth characteristics and phytochemicals of canola (Brassica napus) grown under UV radiation and low root zone temperature in a controlled environment

We determined the effects of UV radiation and low root zone temperature on growth characteristics and phytochemicals of Brassica napus (canola) cultivated in a controlled environment (25/20 °C 16/8 [light/dark]; 70% relative humidity; 1000 µmol mol−1 CO2 with photosynthetic photon flux density of 100 and 200 µmol m−2 s−1 for 7 and 18 days, respectively). The 18-day-old B. napus plants were treated for 5 days with two nutrient solution–temperature regimes (normal temperature [NT] and low-temperature [10 °C; LT]) and three levels of UV radiation (0, 0.3, and 0.6 W m−2). Treatment with 0.6 W m−2 UV decreased quantum efficiency of photosystem II the most. Most growth characteristics decreased under LT + UV treatments. Treatments with 0.6 W m−2 UV, compared to those without UV, significantly inhibited shoot height. LT + 0.3 and +0.6 UV decreased shoot height the most. Temperature (T) × UV interaction did not affect most growth characteristics except leaf area, specific leaf weight, and shoot water content. Antioxidant capacity (total ORAC) resembled lipophilic ORAC and showed the highest value in the LT + 0.6 UV treatment. T × UV interaction did not affect ORAC values, although LT + 0.3 UV and LT + 0.6 UV treatments produced the highest values. Both LT and UV radiation enhanced the total phenolic content, and in the combined treatments, it was two times that of the control. UV intensities (0.3 and 0.6 W m−2) remained constant regardless of variation in root zone temperature. UV radiation enhanced total flavonoid content equally across different intensities; LT + 0.6 W m−2 UV treatment produced a relatively high value. Thus, LT and UV negatively affected plant growth parameters, except total dry weight, whereas LT, UV, or LT + UV positively affected antioxidant properties, total phenolics, and flavonoids, suggesting the potential of using an LT treatment in a hydroponic system as well as UV radiation to enhance growth performance of greenhouse and factory plants.

Desain Kontrol Sistem Telemetri pH Larutan Nutrisi Hidroponik Berbasis Fuzzy Logic

The utilization of bare areas like narrow tract, building roof, or unused warehouse can be maximized as agricultural land using hydroponics system. Hydroponics is a cultivation technique by using nutrient solution. The plant nutrient is an alternative soil which relate with water acidity (pH), that has reaction with nutrient solubility to plant fertility. In fact, pH of the nutrients can change because of many factors like media of plant. The temperature of nutrient solution affect an ion nutrient absorption by plant root. The higher temperature reduces plant root ability to absorb water and ion nutrients. The more advanced technological developments, the agriculture can be controlled automatically and monitored remotely. The aim of this research is to make design control ph, volume and nutrients solution using fuzzy logic and zigbee pro communication for telematics control of plant hydroponics. The result of this experiment shown that fuzzy logic has effectiveness to control pH of hydroponics. It needs 429 seconds to setting point of range pH 5 ppm to 7 ppm and 459 seconds to setting point of range pH 9 ppm to 7 ppm.

Automation System and Monitoring in the Hydroponic Cultivation Process Integrated with Internet Network

The monitoring system in nutrient solution is something that must be considered in the process of hydroponic cultivation, because it is from this nutrient solution that ensures the result and quality of the hydroponic plant itself. Important variables such as acidity, temperature and concentration of nutrient solution are the values that determine whether or not the nutrient solution will be given to the hydroponic plant. Important variables in improper nutrient solutions will make the hydroponic cultivation process for crop failure. This research uses a PH sensor that serves to detect the acidity level of the nutrient solution and the DHT11 temperature sensor which functions to read the condition of the nutrient solution temperature and the TDS sensor detects the concentration of the nutrient solution. The microcontroller used is the type of Atmega328 which is used as a processing of all inputs and outputs. This monitoring system is connected to the internet so that all sensor reading values can be viewed through an Android phone and can be accessed via the Web, so that the monitoring process can be done remotely. From the test results obtained prove that this system has been successfully integrated and is able to work well according to the desired target, which can monitor the acidity and temperature conditions in hydroponic plants that can be accessed directly through mobile phones and has been integrated with the internet network.&#x0D; &#x0D; Keywords— automation; monitoring; cultivation; hydroponics; internet&#x0D;

Hydroponics Reservoir Temperature Monitoring and Controlling System under Greenhouse Condition

An automated reservoir temperature monitoring and controlling system for hydroponic system was developed, calibrated and validated in this study. The automated monitoring and controlling system was developed to monitor and control the reservoir temperature of nutrient solution in hydroponic system. The greenhouse available at the Center for Hydroponics and Aquaponics Technology (CHAT) and locally available materials and hardware for the hydroponics and automation were used in the development of the system. These devices were designed and assembled based on the conceptual framework of the study. The reservoir temperature sensor sends signal to the microcontroller which triggers the turning on/off of water chiller and the mixer. The instruments used were calibrated prior to the performance evaluation and obtained calibration equation for the water temperature sensor is y = x + 0.37. Validation of the automated reservoir temperature monitoring and controlling system was done and the recorded maximum temperature is 31 °C and the minimum temperature is 24 °C. The lettuce planted during the validation has an average height of 14.61 cm and the average leaf count of 12 for the lettuce crops during the 4th week after planting. A total of 4.78 kg of lettuce crop was harvested with an average of 20.6 grams per lettuce crop was obtained. Based on the performance evaluation and validation done on the automated reservoir temperature monitoring and controlling system, it was found to be reliable. This system becomes useful in reducing labor cost, and allows for real-time monitoring of reservoir temperature, therefore increasing farmers’ crop productivity and income.