Hydroponic Production Systems Research Articles

Occurrence of Pseudomonas cichorii Causing Midrib Rot of Lettuce Under Hydroponic Cultivation in Chile

In Chile, lettuce is the vegetable that has increased in cultivated area the most in recent years, reaching 8,309 ha. The Coquimbo Region contributes the most to this growth in production with 3,284 ha in 2022 (ODEPA 2023). Most lettuce is grown under open field conditions, but there is significant production in greenhouses and an increase in hydroponic production systems (INIA 2017). During April to June 2021 and 2022 in the Coquimbo Region, butterhead-type lettuce seedlings (Lactuca sativa) cv. Neil, cultivated under a hydroponic system, showed severe brown to black lesions in the leaves and midrib (Figure S1). To determine the etiology of this problem, samples of diseased plants were taken. Pieces of symptomatic tissue were macerated, and the extract was spread on nutrient agar (NA) and on King's B medium (KB) and incubated at 23°C for 48 h. The bacterial colonies observed were predominantly circular, creamy-white in color with irregular margins and fluorescent in KB medium. Isolates were gram-negative strictly aerobic. LOPAT test (Lelliot et al. 1966) results of two selected isolates were: levan production (-), oxidase reaction (+), potato soft rot (-), arginine dihydrolase production (-), and tobacco hypersensitivity (+), which corresponds to the profile of Pseudomonas cichorii. Molecular identification was performed through amplification and sequencing of the 16S rRNA (GenBank Accessions No. OR540674 to OR540675), gyrB and rpoD genes (Hwang et al. 2005; Sarkar and Guttmann 2004) (GenBank Accessions No. OR558279 to OR558282). BLAST analysis of the 16S rRNA gene of the isolates resulted in a match with a 99.86% identity with P. cichorii type strain ATCC 10857 (NR_112070.1). BLAST analysis of gyrB and rpoD resulted in a match with a 100% (630/630 bp) and >99% (546/550 bp) identity respectively, with strains of P. cichorii. Five six-month-old lettuce plants cv. Desert Storm were pricked in the midrib with a toothpick smeared with a fresh colony grown on KB medium. Seven days after inoculation, the plants showed dark brown, watery lesions, characteristic of damage caused by P. cichorii (Figure S1). Bacteria were isolated again from the inoculated plants and were identified as P. cichorii using LOPAT and molecular identification techniques. Midrib rot caused by P. cichorii was reported as an emerging disease of greenhouse-grown lettuce by Cottyn et al. (2009). In Chile, P. cichorii was previously described affecting nectarine fruits (Pinto de Torres and Carreño Ibañez 1983) and reported as a pathogen of lettuce among others horticultural crops by Servicio Agrícola y Ganadero of the Government of Chile (Acuña 2008), but this is the first report of P. cichorii affecting hydroponic lettuce plants in Chile. These results will be the basis of future studies to evaluate the origin of the infection, the potential dissemination, and the implementation of disease management to avoid the damage caused by this bacterium in hydroponic systems in this crop of growing importance in Chile.

Enhanced vegetable production in hydroponic systems using decontamination of closed circulating fluid

While plant microorganisms can promote plants by producing natural antibiotics, they can also be vectors for disease transmission. Contamination from plant management practices and the surrounding environment can adversely affect plants, leading to infections and hindered growth due to microbial competition for nutrients. The recirculation of nutrient-rich fluids can facilitate the transport of microorganisms between vegetables in the hydroponic production system. This issue can be addressed through the application of the decontamination method in the hydroponic liquid. Ultraviolet light (UV-C) has been employed for microbiology, and its effects on lettuce were evaluated in this study. This study aims to assess the effectiveness of a decontamination system using UV-C in hydroponic solutions during nutrient recirculation in hydroponics. We evaluated the time required for lettuce plants to reach their maximum height, as well as their pigment content, phenolic compounds, antioxidant capacity, and micro and macronutrient levels. The evaluation was conducted under two photoperiods (18 and 20 hours) in lettuce samples exposed to UV-C in the hydroponic fluid, with control groups not exposed to UV-C. The application of the UV-C decontamination system in hydroponic circulation water containing nutrients accelerated plant growth while maintaining nutritional values equal to or higher than those in the control groups without such a system. The results of microorganism control highlight the potential application of this technique for enhancing and expediting vegetable production. This approach reduces production time and enhances nutrient absorption and the content of certain compounds and minerals.

NON-CIRCULATION HYDROPONIC LETTUCE (Lactuca sativa L. var. Rincon) PRODUCTION USING COMMERCIALLY AVAILABLE NUTRIENT SOLUTION

This study assessed the production performance of lettuce using different simple nutrient addition programs (Yamasaki, MasterBlend, SNAP, Nutrihydro and Hydroplus) compared to organic fertilizer (Biovoltin) with water as a negative control in a Kratky hydroponic system. The crop experiment was conducted at the Institute of Agriculture, Camiguin Polytechnic State College – Catarman Campus, Tangaro, Catarman, Camiguin from January 25, 2022 to March 10, 2022. The study was laid in a Randomized Complete Block Design with seven (7) treatments and three (3) replications at eight plants per treatment. Tukey's Honest Significant Difference (HSD) was used to compare the significant differences between treatment means. Results showed a highly significant differences in the horticultural and root development characteristics, yield parameters, nutrient solution consumption and quality of nutrient solution, and sensory quality except for the survival rate, non-marketable head weight, and pH at 31 DAT. Our results showed that the use of SNAP solution could be used effectively to increase the overall production performance of lettuce. The use of Nutrihydro, Hydroplus, Yamasaki and Masterblend were also promising for its production performance. It can be concluded that the nutrient solution affects the production performance of lettuce in a hydroponic production system. However, the potential use of these various simple nutrient addition programs should be further tested for verification at different growing seasons to elicit substantial conclusions.

Vitaminas afetam a morfofisiologia da alface em sistema hidropônico?

ABSTRACT Technologies once applied exclusively in conventional systems have maximized gains in hydroponic systems; however, they still need information for proper use. Thus, the study aimed to evaluate the effect of foliar application of thiamine and niacin on growth and gas exchange activities in two lettuce cultivars in an ebb and flow hydroponic system. The completely randomized design (CRD) was used with four treatments and eight replications. The treatments were as follows: T1 - control, T2 - thiamine at a concentration of 200 mg L-1, T3 - niacin at 200 mg L-1, and T4 - thiamine and niacin combined at 100 mg L-1 of each vitamin. Each experimental plot consisted of a lettuce plant. The combined application of thiamine and niacin stood out, increasing the activity of gas exchange of lettuce plants and increasing by about 30% the fresh mass, concerning the control, for both cultivars, followed by the isolated application of niacin. For thiamine, the application alone did not result in significant changes. The vitamins affect the morphophysiology of lettuce, where the use of niacin has the potential for use in hydroponic production systems. Its combined use with thiamine increases this potential, with a synergistic effect between the compounds being verified.

Effect of different growing media on pomological and phytochemical parameters of Fragaria vesca ʻYellow Wonderʼ and Fragaria ×ananassa ʻCamarosaʼ: a comparative study

BackgroundStrawberries are one of the most widely cultivated fruits in the world, and their popularity continues to grow due to their unique taste, high nutritional value, and numerous health benefits. The success of strawberry cultivation depends largely on the quality of the growing media used. In recent years, there has been a growing interest in soilless media as a sustainable alternative to traditional soil-based growing methods. This study aimed to compare the effect of different growing media, both soil and soilless (Hydroponic Production System) media, on the fruit quality and phytochemical contents of two cultivars of strawberry (Yellow Wonder and Camarosa) in a greenhouse.ResultsThe values of Fruit weight, fruit firmness, and SSC were higher in soilless media than in soil media. In addition, ʻCamarosaʼ was higher than ʻYellow Wonderʼ in these characteristics. The rates of glucose and fructose were higher in soil media than soilless media, and ʻYellow Wonderʼ was higher than ʻCamarosaʼ in the rates of glucose and fructose. The values of total phenolic content and antioxidant capacity were higher in soil media, and also ʻYellow Wonderʼ was found to have more total phenolic content and antioxidant capacity than ʻCamarosaʼ. In terms of mineral contents, ʻYellow Wonderʼ had higher values than ʻCamrosaʼ in both media. When the results of the study were examined in general, Camarosa red strawberry variety was found to be higher than ʻYellow Wonderʼ in pomological characteristics.ConclusionsPomological values increased in both strawberry cultivar in soilless media. In terms of phytochemical properties, the ʻYellow Wonderʼ had higher values than the ʻCamarosaʼ. Also, Phytochemical contents were higher in the soil media compared to the soilless media.

Optimization of Water Use Efficiency of Hydroponic Maize Fodder Production System under Different Microclimatic Conditions

Aims: Hydroponic method of producing fodder is an advanced technique which helps to achieve very high-water use efficiency (WUE). The main objective of the study was to optimize WUE by controlling the system and reducing the stress on the crops to give higher yield.
 Study Design: The experiment employed a statistical design known as Completely Randomized Design Place and duration of the study: The experiment was carried out in the Precision Farming Development Centre (PFDC) building, Kelappaji College of Agricultural Engineering and Technology (KCAET), Tavanur during May and June 2021.
 Methodology: Three different water application methods namely, mist (I1), micro sprinkler (I2), fogger (I3) was selected. Artificial light source of LED red (L1), LED blue (L2), LED red + blue (L3) and sunlight (L4) were considered for the study. Statistical analysis was conducted to understand the significance of different treatments used in the experiment in optimizing yield and WUE of the system.
 Results: Highest yield was observed in treatment involving fogger irrigation and LED red + blue (2.11 kg/tray) with highest WUE (515.43 kg/m3) compared to other treatments. Seed to fodder ratio obtained was 1:6. Chemical analysis showed higher percentage of crude protein (13.56%) and crude fibre (12.59%) in this treatment. Higher growth of green fodder under artificial light source can be attributed to the continuous supply of energy compared to highly varying sunlight and also the uniform distribution of water by fogger irrigation which maintained favourable condition for fodder growth.
 Conclusion: Results clearly indicated that growing green fodder with artificial light source (LED red + blue) and water supply with fogger can be recommended to farmers for achieving better growth of green fodder for domestic animals.

Performance analysis of two typical greenhouse lettuce production systems: commercial hydroponic production and traditional soil cultivation.

Due to the shortage of land and water resource, optimization of systems for production in commercial greenhouses is essential for sustainable vegetable supply. The performance of lettuce productivity and the economic benefit in greenhouses using a soil-based system (SBS) and a hydroponic production system (HPS) were compared in this study. Experiments were conducted in two identical greenhouses over two growth cycles (G1 and G2). Three treatments of irrigation volumes (S1, S2, and S3) were evaluated for SBS while three treatments of nutrient solution concentration (H1, H2, and H3) were evaluated for HPS; the optimal levels from each system were then compared. HPS was more sensitive to the effects of environmental temperature than SBS because of higher soil buffer capacity. Compared with SBS, higher yield (more than 134%) and higher water productivity (more than 50%) were observed in HPS. We detected significant increases in ascorbic acid by 28.31% and 16.67% and in soluble sugar by 57.84% and 32.23% during G1 and G2, respectively, compared with SBS. However, nitrate accumulated in HPS-grown lettuce. When the nutrient solution was replaced with fresh water 3 days before harvest, the excess nitrate content of harvested lettuce in HPS was removed. The initial investment and total operating cost in HPS were 21.76 times and 47.09% higher than those in SBS, respectively. Consideration of agronomic, quality, and economic indicators showed an overall optimal performance of the H2 treatment. These findings indicated that, in spite of its higher initial investment and requirement of advanced technology and management, HPS was more profitable than SBS for commercial lettuce production.

Performance evaluation of pechay (Brassica rapa var. chinensis) using different organic growing media under hydroponic system

There is a growing interest among vegetable growers in using locally available growing media in hydroponic production. This study assessed the growth and yield of pechay, nutrient solution consumption of the plant, and its quality using different growing media (foam, coco peat, raw rice hull, raw saw dust, vermicompost, composted rice straw, composted rice hull) in a Kratky hydroponic system at the Institute of Agriculture, Camiguin Polytechnic State College-Catarman Campus, Tangaro, Catarman, Camiguin from June 10, 2021, until July 15, 2021. The study was laid in a Randomized Complete Block Design with seven treatments and three replications. Tukey’s Honest Significant Difference (HSD) was used to compare the significant differences between treatment means. Results showed that the type of growing media did not significantly affect the pechay growth performance, insect pests and disease incidence, nutrient solution consumption, and final quality of the hydroponic nutrient solution. However, a highly significant difference was observed in horticultural root development characteristics except for the percentage of root per plant and survival rate. In terms of yield parameters, highly significant differences were observed except for the number of marketable and non-marketable yields, the weight of non-marketable yields, and the harvest index. Our results showed that the use of foam could be used effectively to increase production under a hydroponic system. The use of organic growing media (raw rice hull, vermicompost, raw saw dust, coco peat) was also promising for their growth and yield performance. It can be concluded that the growing media affects the growth and yield of pechay in a hydroponic production system; however, the potential use of these various growing media should be further tested for verification.

Development of Pot Hydroponic Production System and Auxiliary Machines for Grafted Cactus

Development of Pot Hydroponic Production System and Auxiliary Machines for Grafted Cactus

Application of electrochemically activated solution to control pathogens of hydroponic solution

In the current integration trend, high-tech agriculture is an inevitable direction for agricultural developing countries. In particular, hydroponics is a commonly used farming technique due to many advantages: no soil, space saving, no weeds, easy control of influencing factors, double yield. Hydroponic crop production systems are used worldwide to grow flowers, foliage, litter, and fruit and vegetable crops. Like other farming methods, hydroponics still has problems with pests and diseases that cause serious damage to the harvest that have not been completely resolved. One of the sources of pathogens is the hydroponic solution. Many methods to kill bacteria and fungi in hydroponic solutions have been studied. However, some methods gave low efficiency, others gave high efficiency but it caused secondary environmental pollution. Electrochemical activated solution (EAS), produced from dilute sodium chloride (NaCl) solution, has been wide known as a super disinfectant solution with high ability to kill most bacteria and fungi and is safe for humans. In this study we were forced on determine the ability to control pathogens in hydroponic solution of EAS, the effects of EAS on hydroponic solution properties and the growth of Brassica juncea in the mixed of EAS – hydroponic solution. Difference volume of EAS were added into hydroponic solutions and mixed for 30, 45, 60, 120 or 180 min. The most effective mixed solution (mixed ratio and time) was selected to apply to cultivate Brassica juncea. The results show that EAS has the ability to control pathogens in hydroponic solution very effectively, replacing other harmful chemicals. When increasing the volume EAS added (higher ACC of mixed solution) or the exposure time the TDS and ORP index of hydroponic solution were raised slightly while pH value was slightly dropped and the total coliform counts decreased significantly. The total coliform counts of mixed solutions reduced over the exposed time. However, the increasing rate of killing ability of EAS was decreased (along with ACC of solutions). Meanwhile, there was no obvious change in the nitrate concentration. The most effective mixed ratio EAS: hydroponic solution and exposure time for pathogens control were 2.5:500 with 30 min or 1.5:500 with 90 min. The mixed ratio of 1.5:500 with 90 min of exposure time were recommended because of its lesser changes on the properties of hydroponic solution. The mixed EAS - hydroponic solution did no negative effect to the growth of Brassica juncea in comparison with original hydroponic solution.

Evaluation of a Proprietary Plant Extract to Suppress Bacterial Canker and Improve Yield in Hydroponic Tomatoes

Bacterial canker of tomato, caused by the systemic bacterial phytopathogen Clavibacter michiganensis, can result in significant economic losses in hydroponic tomato production systems. Lacking effective bactericides, the disease is managed primarily by clean seed procedures, sanitation, and quarantine. Plant extracts have been shown to display antimicrobial activity and/or induce plant resistance to disease. We tested the efficacy of AOMMA-Agro, an Organic Materials Review Institute-listed proprietary blend of plant extracts, in suppressing bacterial canker and improving yield and shelf life in hydroponic tomato trials over 2 years. Experiments were conducted in a greenhouse with ‘Campari’ tomatoes transplanted into coconut coir blocks and grown under hydroponic conditions. Plants were trellised, pruned, and harvested according to commercial standards. AOMMA-Agro was applied weekly or biweekly as a foliar spray and inoculated with C. michiganensis. Plants treated with water and inoculated or not inoculated served as controls. Disease severity was relatively low in both years; however, disease progress was significantly lower for plants inoculated and treated biweekly, but not weekly, with AOMMA-Agro than for nontreated, noninoculated plants in one of two trials. Similar results were observed for C. michiganensis incidence determined using qPCR. Marketable yield was 29 and 44% higher from inoculated plants treated biweekly with AOMMA-Agro than from nontreated, noninoculated plants in the two experiments. These results support the use of AOMMA-Agro as a potential option for bacterial canker management and yield enhancement in hydroponic tomato greenhouse production systems.

HYDROPONIC LETTUCE (Lactuca sativa L. var. Lalique) PRODUCTION USING COMMERCIALLY AVAILABLE NUTRIENT SOLUTIONS

This study was carried out to assess commercially available nutrient solutions (Yamasaki, MaterBlend, Snap, Nutrihydro, and Hydroplus) in hydroponic lettuce production in comparison to organic fertilizers (Biovoltin) with water as a negative control. The crop experiment was conducted at the Institute of Agriculture, Camiguin Polytechnic State College-Catarman Campus, Tangaro, Catarman, Camiguin, from January 25, 2022, until March 10, 2022. The study was laid in a Randomized Complete Block Design with seven (7) treatments and three (3) replications at eight plants per treatment. Results of the study showed that considering horticultural growth and root characteristics, lettuce grown on Masterblend produced taller plants, longer leaf blades, and wider canopy, SNAP exhibited broader leaves, and Yamasaki with the greater number of leaves, longer roots, higher root volume, root fresh and total fresh weight while all treatment exhibited a 100% survival rate. In terms of yield, Masterblend had the higher fresh head weight per plant, the weight of marketable head per box, and total yield, Yamasaki, Masterblend, SNAP, and Hydroplus had a higher number of marketable yields, and Hydro plus had a higher harvest index. SNAP was considered best overall in terms of sensory quality attributes and marketability. Using the SNAP solution resulted in higher net return, net profit margin, and return on investment, followed by Masterblend, Hydroplus, and Yamasaki. It can be concluded that using commercially available nutrient solutions affects the growth and yield of lettuce in a hydroponic production system. However, its potential used should be further tested for verification under different growing seasons to elicit substantial conclusions.

Role of Plants to Restore Nature and to Increase Food Productions Simultaneously

<b>Summary:</b> This editorial writing gives the reader(s) insights of some of our last issue's published works, what the authors mentioned and what significance they provide. Moreover, this writing gives the audience(s) some of recent information that how plants play role to restore our nature and to make foods for the people. The plants from terrestrial to ocean here tried to mention to sink CO2, which is considered as a major factor for increasing world temperature. Hopefully, the witting will help reader(s) about the journal's last issue in a brief along with the main theme of this editorial.<br/> The current world is facing problems related to climate change which would create a substantial crisis in the food production system in the future (1). Not only changing pattern of climate is an only precursor for this situation, but also the increasing population. Many regions of the world have already witnessed how the overcrowded populations surge the many other problems associated with climate change, greenhouse effect for example (2). As the population increase, the land area with plants decreases to support the additional amount of population to provide food and shelter mainly (3). Thus, the degradation of nature and the food crisis are most probably due to the outcomes of plants diminishing abruptly (4).<br/> Now researchers are trying to develop the ideas to set up activities to save the nature as well as to solve the upcoming food crisis. They are developing new strategies or techniques to increase plants or plants derived foods through advanced and alternative farming approaches (5,6). Recently, Khatun et al. reported that onion can be produced hydroponically where there are several possibilities to use the methods as environment-friendly (7). They used several types of supporting media, environment-friendly inert materials, to produce onion without using soil that would be an indicative way for many nations where huge lands needed to produce onion. Besides, satellite-associated remote sensing in the crop fields to monitor crop yielding is a good example of technological advancement which can maximize productivity without affecting the fields (8). Even, the use of artificial intelligence in monitoring crop fields and hydroponic production system can ensure the proper fertilizer or nutrient utilization, which is considered as one of the reasons to degrade other farm fields nearby (9). Moreover, plants, seaweeds mostly in the ocean, act as a sink of CO2 which is identified as the main cause for greenhouse effects in the earth's atmosphere (10).<br/> Hopefully, in the future plants will play a vital role at the policy level by most of the nations because of international organizations rising awareness towards the necessity of plants for the world. Scientists will develop more techniques that will provide food and at the same time will remove hazardous chemicals from the environment (11). Many barren lands, destructing forests, and degraded ecosystems will be green again with the help of the advancement of plant sciences. Terrestrial to aquatic everywhere plants will be a game-changer to abate environmental degradation and to increase productivity. Already scientists emphasized that plants and their photosynthetic capacity can solve most of the current environmental problems directly or indirectly (12).<br/> In conclusion, future research on all areas of plant science will embrace the positive aspects of restoring nature along with increasing food productions. Therefore, to restore nature as well as to solve the food crisis, plants have unavoidable significance.

Sistemas semi-hidropônico e ebb-and-flow para cultivo de copo-de-leite

Abstract The soilless cultivation of plants is an alternative for the production of flowers with high quality. Calla lily is normally produced on soil benches, but have shown some limitations as bacterial infections occur. One alternative may be a soilless cultivation. Hence, experiments were conducted with the objective to evaluate the development of calla lily in two types of hydroponic production systems. The semihydroponic system was tested using as substrates or growing media such as, coconut fiber, sand, vermiculite, and phenolic foam sheets. For the other system, ebb-and-flow, the substrates tested were vermiculite, coconut fiber, and expanded clay. Two different nutritional solutions were tested in both systems. in the semihydroponic system. In general, calla lily was adapted and showed a good development in a soilless cultivation. The best initial development of the calla lily was provided using vermiculite and sand as substrates on semihydroponic. And for the ebb-and-flow system, coconut fiber induced better development. As conclusion, hydroponic cultivation systems are efficient for the initial development of calla lily. The recommended substrates are those with lower porosity, such as sand, vermiculite, and coconut fiber.

Comparing Efficacy of Different Biostimulants for Hydroponically Grown Lettuce (Lactuca sativa L.)

Biostimulants can enhance horticultural crop production. However, their application in hydroponically grown lettuce is still limited, and information regarding their relative efficacy is lacking. A greenhouse trial was conducted to address this issue. Five nutrient solution treatments were evaluated on two lettuce cultivars: butterhead and red oak-leaf. The treatments included a half-strength modified Hoagland solution (Hs-H); a full-strength modified Hoagland solution (Fs-H); and Hs-H supplemented with 50 mg L−1 fulvic acid (FA), 334 mg L−1 seaweed extract (SE), or 5 mL L−1 gamma polyglutamic acid (PGA). The results indicated that the shoot biomass observed after biostimulant supplementation was significantly greater than or comparable to that observed with Fs-H. Nutrient solutions supplemented with SE and PGA led to a greater increase in the root biomass than that realized with Hs-H and Fs-H treatments. The Hs-H + FA treatment resulted in the lowest root-to-shoot ratio on a fresh weight basis among all treatments. The nitrate concentration in the shoot was significantly reduced following biostimulant supplementation compared to that realized with Fs-H and Hs-H treatments. Nutrient solutions supplemented with SE and PGA also decreased soluble sugar concentrations compared to that achieved using Hs-H and Fs-H treatments. FA and SE improved nutrient uptake for both cultivars, but PGA had a minimal effect on nutrient uptake. The two cultivars varied in their responses to biostimulant supplementation with regard to biomass, quality traits, and nutrient uptake. This study supports using fulvic acid and seaweed extract, rather than γ-PGA, in hydroponic lettuce production systems.

History of Controlled Environment Horticulture: Greenhouses

Modern greenhouses are intensive farming systems designed to achieve high efficiency and productivity. Plants are produced year-round in greenhouses by maintaining the environment at or near optimum levels regardless of extreme weather conditions. Many scientific discoveries and technological advancements that happened in the past two centuries paved the way for current state-of-the-art greenhouses. These include, but are not limited to, advancements in climate-specific structural designs and glazing materials, and temperature control, artificial lighting, and hydroponic production systems. Greenhouse structures can be broadly grouped into four distinct designs, including tall Venlo greenhouses of the Netherlands, passive solar greenhouses of China, low-cost Parral greenhouses of the Mediterranean region, and gutter-connected polyethylene houses of India and African countries. These designs were developed to suit local climatic conditions and maximize the return on investment. Although glass and rigid plastic options are available for glazing, the development of low-cost and lightweight plastic glazing materials (e.g., polyethylene) enabled widespread growth of the greenhouse industry in the developing world. For temperate regions, supplemental lighting technology is crucial for year-round production. This heavily relies on advancements in electro-lighting during the 19th and 20th centuries. The development of hydroponic production systems for the controlled delivery of nutrients further enhanced crop productivity. This article addresses important historical events, scientific discoveries, and technological improvements related to advancements in these areas.

Effect of Hydroponic and Conventional Production Systems on Plant Growth Performance and Nitrate Content of Green Coral Lettuce (Lactuca sativa var. Crispa)

Overfertilization on leafy vegetables could accumulate high nitrate content. Exceeded recommended limit of nitrate content can cause detrimental effects on the environment and human health, such as methemoglobinemia and stomach cancer. Green coral lettuce (GCL) is a leafy vegetable commonly grown under various production systems. Production system and physiological age have affected the growth and accumulation of nitrate levels in most leafy vegetables. Therefore, this study aims to determine the effects of hydroponic and conventional production on the growth performance and nitrate concentration of GCL at different harvest ages. This research was conducted in a randomized complete block design with a factorial arrangement of treatments. A stagnant hydroponic was prepared using stock A and B complete Hoagland nutrient solutions as liquid fertilizer. A commercial biofertilizer (NPK 8: 8: 8) was applied at the rate of 100 g per plant. Plant growth performance, including plant height, number of leaves, and leaf length, was measured at 7, 14, 21, 28, 31, 34, 41, and 44 days after transplanting (DAT). The fresh weight and nitrate content were measured at 31, 34, 41, and 44 DAT. The results showed hydroponic GCL exhibited higher plant height than conventional GCL. However, both productions were not significantly affected regarding the number of leaves, leaf length, and fresh weight. At 41 and 44 DAT, the hydroponic GCL was markedly higher in nitrate content than conventional. This study found that conventional production was recommended for GCL because lower in nitrate content compared to hydroponic and fair in growth performance.

Effect of Hydroponic and Conventional Production Systems on Plant Growth Performance and Nitrate Content of Green Coral Lettuce (Lactuca sativa var. Crispa)

Overfertilization on leafy vegetables could accumulate high nitrate content. Exceeded recommended limit of nitrate content can cause detrimental effects on the environment and human health, such as methemoglobinemia and stomach cancer. Green coral lettuce (GCL) is a leafy vegetable commonly grown under various production systems. Production system and physiological age have affected the growth and accumulation of nitrate levels in most leafy vegetables. Therefore, this study aims to determine the effects of hydroponic and conventional production on the growth performance and nitrate concentration of GCL at different harvest ages. This research was conducted in a randomized complete block design with a factorial arrangement of treatments. A stagnant hydroponic was prepared using stock A and B complete Hoagland nutrient solutions as liquid fertilizer. A commercial biofertilizer (NPK 8: 8: 8) was applied at the rate of 100 g per plant. Plant growth performance, including plant height, number of leaves, and leaf length, was measured at 7, 14, 21, 28, 31, 34, 41, and 44 days after transplanting (DAT). The fresh weight and nitrate content were measured at 31, 34, 41, and 44 DAT. The results showed hydroponic GCL exhibited higher plant height than conventional GCL. However, both productions were not significantly affected regarding the number of leaves, leaf length, and fresh weight. At 41 and 44 DAT, the hydroponic GCL was markedly higher in nitrate content than conventional. This study found that conventional production was recommended for GCL because lower in nitrate content compared to hydroponic and fair in growth performance.

Opportunities and constraints in hydroponic crop production systems: A review

Hydroponic crops can be grown using a variety of media and production systems (NFT system, wick system, drip system, ebb flow system etc.). EC and pH management are required to successfully handle these hydroponic systems (water quality and nutrient solution maintenance). These hydroponics systems have gained rapid adoption due to disciplined management of their resources and food production. Although the hydroponic system was developed in a closed-loop system, and substrate nutrition increases production, it is not cost-effective to develop this system on big scale. It is critical to design a low-cost hydroponic structure that decreases reliance on human labour and lowers overall startup cost in order to increase the commercialization of hydroponic farms. We need more research to develop more productive and cost-effective organic nutrient solutions and improve hydroponic crop production systems. In this review paper, we will discuss the opportunity and challenges in hydroponic crop production systems.

Nutrient Dosing Framework for an Emission-Free Urban Hydroponic Production

The urban hydroponic production system is accelerating industrialization in step with the potentials for reducing environmental impact. In contrast, establishing sustainable fertilizer dosing techniques still lags behind the pace of expansion of the system. The reproducibility of root-zone nutrient dynamics in the system is poorly understood, and managing nutrients has so far primarily relied on periodic discharge or dumping of highly concentrated nutrient solutions. Here, we assayed root-zone nutrient concentration changes using three possible nutrient dosing types. Three Brassica species were hydroponically cultivated in a controlled environment to apply the nutrient absorption and transpiration parameters to the simulation analysis. We found that nutrient dosing based on total ion concentration could provide more reproducible root-zone nutrient dynamics. Our findings highlight the nutrient absorption parameter domain in management practice. This simplifies conventional nutrient management into an optimization problem. Collectively, our framework can be extended to fertilizer-emission-free urban hydroponic production.