Organic Hydroponics Research Articles

The first step to organic hydroponics – preparing microbial culture solutions with easily accessed household liquid organic fertilizers in a subtropical farm

The first step to organic hydroponics – preparing microbial culture solutions with easily accessed household liquid organic fertilizers in a subtropical farm

Hidroponik Organik Berbasis Pupuk Organik Cair

Organic hydroponics based on liquid organic fertilizer. Research on the cultivation of Kailan (Brassica oleracea var. achepala) plants using an organic hydroponic system based on organic fertilizers (POC), was conducted at the experimental garden of Pasraman Unud Jimbaran from March to June 2020. The liquid organic fertilizer used consisted of two types of MOL, namely bamboo shoots MOL and banana weevil MOL. The purpose of this research is to find an organic medium (nutrient solution) that is cheap, easy and environmentally friendly as an alternative substitute. AB mix (inorganic nutrients) which has been used in hydroponic systems. The experimental design used in this study was a Randomized Block Design. Using liquid organic fertilizer from MOL Bamboo Shoots (R) and MOL Banana Hump (B). The treatments consisted of: K (without MOL); K+ (without MOL +AB mix) ; R1& B1 ( 50 ml/L ); R2 & B2 (100 ml/L) ; R3 & B3 (150 ml/L); and R4 & B4 (200 ml/L), there were 10 treatments with 3 replications, so there were 30 experimental units. Initial analysis of the media was carried out on the levels of N, P, K, pH and EC. Parameters measured were number of leaves, plant height, wet weight, plant dry weight. The results showed that hydroponics by only relying on liquid organic fertilizer as a source of nutrition, was not able to support normal plant growth. Wet weight, dry weight and plant height of Kailan in the MOL treatment of banana weevil and MOL of bamboo shoots showed much smaller results, namely 1/10 compared to the AB mix (K+) treatment.

Potential Utilization of Catfish Wastewater, Livestock Manure and Waste of Fish as Media and Nutrition for Organic Hydroponic

Organic Hydroponics is cultivation on a planting medium without soil with a source of nutrients obtained from the decomposition of organic materials by microorganisms. Catfish cultivation wastewater and agricultural waste can be used as an alternative planting medium and a source of nutrients in organic hydroponic cultivation systems. This study aimed to determine the plant nutrient content in catfish culture wastewater added with cow dung, chicken manure, trash fish waste, and catfish waste; and to determine the growth of mustard greens and lettuce which were cultivated hydroponically in a growing medium of catfish wastewater added with cow dung, chicken manure, trash fish waste, and catfish waste. The results showed that the solution of catfish culture wastewater added with catfish waste contained nutrients N 220.0 ppm, P 166.3 ppm K 154.4 ppm Ca 65.9 ppm Fe 4.4 ppm; catfish culture wastewater added with trash fish waste contains 50.0 ppm N; P 10.8 ppm; K 173.4 ppm; Ca 219.4 ppm and Fe 3.2 ppm; catfish culture wastewater added with cow dung contained nutrients N 300.0 ppm, P 293.4ppm K 1026.8 ppm Ca 413.6 ppm Fe 64.9 ppm, while those given chicken manure included N 100.0 ppm; P 76.1 ppm; K 471.1ppm; Ca 299.9ppm and Fe 27.3ppm. While catfish culture wastewater contains 55.2 ppm of N nutrients; P 6.4 ppm; K 7.0 ppm; Ca 14.2 ppm; Fe 0.4 ppm. The growth of lettuce in the growing media of catfish culture wastewater given trash fish and catfish was relatively the same, namely 37.7% and 37.9%, respectively. Meanwhile, the growth of mustard pakcoy grown on planting media given chicken manure (47.6%) was higher than the growth of mustard pakcoy grown on cow dung (33.3%). The addition of 50% ABmix nutrients increased the growth of mustard pakcoy on media that was given chicken manure by 81.7%; pakcoy on media that was given cow dung waste by 74.8%; Meanwhile, the addition of ABmix 50% nutrients increased the growth of lettuce on media that was given catfish meal by 64.4%, and on media that was given trash fish meal by 61.9%. Research shows a high potential for using organic waste as a medium and source of organic hydroponic cultivation fertilizer.

Lettuce (Lactuca sativa L. var. Rincon) Production Using Organic Nutrient Solution under Hydroponics System

Lettuce is one of the most widely hydroponically grown crops and studies showed that lettuce has a high yield and good quality under a soilless production. However, the nutrient solution used in hydroponic systems is based on chemical fertilizers and recently, there has been an increased interest in organic hydroponics as the market for organic food continues to grow. The study was conducted to evaluate commercially available organic nutrient solutions (Vermitea, BioVoltin, Ramils, Healthynest) in comparison to conventional inorganic fertilizers (Snap) in hydroponic lettuce production with water as a negative control. The crop experiment was carried out in a plastic polyhouse with a mesh net at the Institute of Agriculture, Camiguin Polytechnic State College – Catarman Campus, Tangaro, Catarman, Camiguin, from November 1, 2021, to December 15, 2021, using a Randomized Complete Blocked Design with three replications. Results of the study showed that among organic nutrient solutions, Treatment 5 (Ramils) and Treatment 7 (Healthynest,), showed comparable results to conventional inorganic fertilizer, Treatment 1 (Snap) in terms of horticultural characteristics, root development, survival rate, yield, and sensory quality attributes and cost and return analysis. However, different organic nutrient solutions exhibited no significant effects on nutrient solution consumption per plant and total nutrient solution consumption. Treatment 5 (Ramils) was considered best overall in terms of sensory quality attributes, overall acceptability and overall marketability except for color, succulence, and bitterness, followed by T1 and T7. Also, Treatment 5 (Ramils) and Treatment 7 (Healthynest) have the highest yield, hence generating the highest net returns, net profit margin, and return on investment.

Organic hydroponics: a US reality challenging the traditional concept of “organic” and “soilless” cultivation

ISHS III International Symposium on Soilless Culture and Hydroponics: Innovation and Advanced Technology for Circular Horticulture Organic hydroponics: a US reality challenging the traditional concept of “organic” and “soilless” cultivation

Effects of Conventional and Bokashi Hydroponics on Vegetative Growth, Yield and Quality Attributes of Bell Peppers.

Due to consumers’ awareness and concern about nutrition and health in different parts of the world, the adoption of organic hydroponics is increasing. This has led to a search for organic nutrient media. One of the viable nutrient sources for organic hydroponics is bokashi compost. The principal objective of this study was to compare the performance of 10% bokashi hydroponics with convention hydroponics for bell pepper production. The different hydroponics influenced vegetative growth parameters largely due to considerable differences in the mineral elements in both hydroponic systems. Stems of conventionally grown plants were significantly (p ≤ 0.05) thicker (10.2 mm) compared to those of the bokashi grown plants (7.3 mm). Conventionally grown plants had significantly (p ≤ 0.05) higher photosynthetic performance than bokashi grown plants; normalized difference vegetation index (NDVI) (78.80 versus 67.49), soil plant analysis development (SPAD; 73.89 versus 38.43), and quantum yield (QY; 0.64 versus 0.49). Leaf superoxide dismutase (SOD) activity in the leaves of bokashi grown plants (0.32 units/mg protein) was significantly (p ≤ 0.05) lower than in the leaves of conventionally grown plants (0.37 units/mg protein). This also corresponded to significantly (p ≤ 0.05) higher leaf sap content in the conventionally grown plant than bokashi grown plants. Furthermore, conventional hydroponics yielded three-fold greater pepper fruit per plant compared to bokashi. After 14 days of storage at 7 °C and 95% relative humidity, the firmness of both groups declined, especially for the bokashi grown fruit (27.73 shore unit), which was significantly lower compared to conventionally grown fruit (35.65 shore unit). However, there was an increase in carotenoid content in fruit grown in both hydroponic systems after storage. In conclusion, although bell pepper plant was successfully cultivated in bokashi hydroponics, the plant performance, fruit yield and postharvest quality were lower than conventional hydroponics. We believe that this study and its approach will provide future research with baseline information on optimizing media of bokashi hydroponics to produce bell pepper.

Effects of Hydrogen Peroxide on Organically Fertilized Hydroponic Lettuce (Lactuca sativa L.)

Hydroponic production typically uses conventional fertilizers, but information is lacking on the use of organic hydroponic fertilizers. Development of microbial communities and biofilm that can reduce dissolved oxygen availability is a difficulty with organic hydroponics. One potential solution is the use of hydrogen peroxide (H2O2) which can reduce microbial populations and decompose to form oxygen. However, information is lacking on the impact of hydrogen peroxide on hydroponic crop performance. The aim of this study was to determine the effects of H2O2 concentrations in deep water culture hydroponics by assessing how it affects plant size and yield in lettuce (Lactuca sativa L.) “Rouxai”. In this experiment, three H2O2 treatments, namely the application of 0, 37.5 or 75 mg/L H2O2 to 4 L aerated hydroponic containers with either conventional or organic fertilizer, were compared. The containers had either fish-based organic fertilizer (4-4-1, N-P2O5-K2O) or inorganic mineral based conventional nutrient solution (21-5-20, N-P2O5-K2O), both applied at 150 mg/L N. Three replicates of each H2O2 treatment–fertilizer combination were prepared resulting in a total of eighteen mini hydroponic containers each with one head of lettuce. There were two growth cycles: fall 2018 and spring 2019. When added to conventional fertilizers, both 37.5 mg/L and 75 mg/L of H2O2 led to stunted growth or death of lettuce plants. However, when 37.5 mg/L of H2O2 was applied to organic fertilizers, the lettuce yield nearly matched that of the conventionally fertilized control, demonstrating that the application of H2O2 has the potential to make organic hydroponic fertilization a more viable method in the future.

Organic Hydroponics Production

Hydroponic culture is a controlled systems use a soilless growing media , supply all of the plant's nutrition in the plant's solutions (water with dissolved fertilizers) , result in higher yields of vegetables, flowers , herbs and others crops. Hydroponic systems derive in many various forms and types. Most traditional hydroponic systems are extremely specialized, controlled-environment production systems. Organic hydroponics is a system that is arranged based on organic agriculture of culture. Different approaches are used for controlling of plant pathogens as physical, natural chemical, biological controls, biofertilizers , bioremediators and integrated pest management. All the required nutrients are supplied in controlled amounts, including organic crops. This article discuss the way for promoting organic hydroponics systems and to help the small-scale producer make decisions about follow this markets , production methods, and disease control.

Uptake and accumulation of lead in Lycopersicon esculentum and Phaseolus vulgaris L. planted on organic hydroponics

ABSTRACT The effects of lead nitrate Pb(NO3)2 on cherry tomato, Lycopersicon esculentum and green beans, Phaseolus vulgaris L. planted on organic hydroponics, was assessed in terms of performance and production at various concentrations (5, 10 and 20 ppm). The residual lead was also determined in experimental soil, nutrient solution, and in experimental plant tissues. Results showed that plant performance was significantly reduced with increasing concentrations of lead contamination. Results also showed that the highest concentrations of lead was found in the plant leaves for green beans, but it was accumulated in the cherry tomato roots rather than in the other tissues, meanwhile the fruits accumulated the lowest concentration for both plants; however, lead contamination has no adverse effects on both plants' production.

Production Potential of Broccoli (Brassica oleracea var. italica) in Hydroponics and Tilapia Based Aquaponics

Hydroponics is a plant growing procedure in water and aquaponics is an eco-friendly, water and energy-saving bio-integrated recirculating aquaculture system that integrates fish farming and vegetable gardening in a symbiotic close loop system. This experiment was carried to observe the production potentiality of broccoli in different type hydroponics like organic hydroponics (T1), inorganic hydroponics (T2) and tilapia based aquaponics systems (T3) each with three replicates for 106 days from 19th February to 4th June, 2018. Three kg vermicompost as T1 was soaked in 90 L water in a drum with a net bag and after that 1 kg vermicompost was added weekly discarding the old one. In case of T2, 28.50 g mixed fertilizer composed of 5g urea, 7.50g TSP, 5g MOP, 5g dolomite, 5g DAP, 0.50 g boron and 0.50 g iron were added in 90 L water and after seven days 22.80 g was added fortnightly. In the aquaponics tank, 10 healthy tilapia fingerlings were released in the same amount of water and 30% protein containing commercial floating feed was fed twice daily at the rate of 3% body weight. Sampling were carried out fortnightly for collecting different parameters of broccoli, fish and water quality. Significantly (P≤0.01) the highest broccoli production was found in T2 (11.79±0.51 tons/ha/106 days) followed by T3 (4.77±0.85 tons/ha/106 days) and the least was in T1 (2.24±0.14 tons/ha/106 days). The analysis showed that, the leaf area, root length and weight were statistically similar in all the three treatments. Fish production was 21.55±3.36 tons/ha/106 days. Nutritional composition of broccoli was also highest in T2 except moisture and ash content. Water dissolved oxygen, electrical conductivity, ammonia, nitrate, nitrogen and phosphorus concentration were suitable for growing broccoli in T2. Whereas in T3, ammonia concentration was high for fish. Broccoli production at higher temperature (31.40 to 36.00°C) in the laboratory than the optimum temperature was possible. Further experiment is needed to carry out in larger areas with different crops and fishes before extension in the field level.

Cobalt-dependent inhibition of nitrite oxidation in Nitrobacter winogradskyi

Nitrobacter winogradskyi is an abundant, intensively studied autotrophic nitrite-oxidizing bacterium, which is frequently used as a model strain in the two-step nitrification of ammonia (NH3) to nitrate (NO3-) via nitrite (NO2-), either in activated sludge, agricultural field studies or more recently in artificial microbial consortia for organic hydroponics. We observed a hitherto unknown cobalt ion-dependent inhibition of cell growth and NO2- oxidation activity of N.winogradskyi in a mineral medium, which strongly depended on accompanying Ca2+ and Mg2+ concentrations. This inhibition was bacteriostatic, but susceptible to natural chelators. l-Histidine effectively restored cell growth and NO2- oxidation activity of N.winogradskyi in mineral media containing Co2+ with >90% recovery. Our results suggest that Co2+ competed with alkaline earth metals during uptake and that its toxicity was significantly reduced by complexation.

Comparisons of commercial organic and chemical fertilizer solutions on growth and composition of lettuce

The objective of this experiment was to assess the effects of organic or chemical nutrient solutions on the growth and composition of lettuce (Lactuca sativa L.) in greenhouse production. Hoagland and Arnon nutrient solution, an organic hydroponics solution, and no fertilization were factored with lettuce cultivars of different phenotypes, iceberg, romaine, loose head, and loose leaf. Lettuce growth was higher with Hoagland and Arnon solution than with the organic fertilizer or with no fertilization. The organic fertilizer increased growth above no fertilizer applied. Hoagland and Arnon solution gave the highest concentration of nitrogen, potassium, magnesium, and iron in the lettuce whereas lettuce grown with the organic fertilizer had the highest phosphorus. Plant nutrient accumulation differed slightly among the cultivars. Hoagland and Arnon solution produced high nitrate in leaves. Nitrate concentrations with organic or no fertilization were low. Loose head or loose leaf cultivars had higher nitrate than romaine or iceberg.

English

For many years, the generation of nitrates from organic sources in order to create nutrient solutions for hydroponics had proved a challenge until lately when microorganisms were introduced to perform this task. The objectives of the current study therefore were to use local microbial consortium to nitrify goat manure in water and to determine microbial diversity in the inoculated consortium. Therefore, microorganisms were sourced from garden soil and natural compost at the Sam Nujoma Marine resources Research Centre (SANUMARC) in Henties Bay Namibia to convert organic nitrogen in goat manure from Utuseb farm near Walvis Bay into nitrates. Results show that microbial consortium from the compost source produced significantly (P< 0.05) more nitrates followed by the garden-soil source, suggesting that it is necessary to add inoculum in order to generate nitrate from goat manure. The ammonia oxidising bacteria (AOB) community from the compost sample’s was dominated by uncultured ammonia-oxidising species followed by uncultured bacterium (both not identified), with the least being Nitrosomonas species. The AOB community from the garden source was dominated by uncultured bacterium, followed by uncultured ammonia-oxidising species and the least being Nitrosomonas species. NOB community from the compost source was dominated by uncultured bacterium, followed by Nitrobacter winogradskyi and Nitobacter vulgaris with the least being Nitrococcus mobilis and Nitrospira moscovensis. For the garden soil microbial source, uncultured nitrite-oxidising bacteria dominated followed by uncultured bacterium, whereas the least species were N. moscovensis and Nitrobacter alkalicus. Moreover, community composition of the compost sample was more diverse than the community from the garden sample. These results maintain that there are other unculturable yet important microbes doing the same job if not better than the known ones, in this case suggesting that there may be other local nitrite-oxidizing bacteria responsible for oxidizing ammonia other than the traditionally known Nitrobacter, Nitrospira and Nitrococcus species.   Key words: Organic hydroponics, ammonification, nitrification, ammonia-oxidizing bacteria, nitrite-oxidizing bacteria.

Analysis of microbial community and nitrogen transition with enriched nitrifying soil microbes for organic hydroponics.

Nitrifying microbial consortia were enriched from bark compost in a water system by regulating the amounts of organic nitrogen compounds and by controlling the aeration conditions with addition of CaCO3 for maintaining suitable pH. Repeated enrichment showed reproducible mineralization of organic nitrogen via the conversion of ammonium ions ( ) and nitrite ions ( ) into nitrate ions ( ). The change in microbial composition during the enrichment was investigated by PCR-DGGE analysis with a focus on prokaryote, ammonia-oxidizing bacteria, nitrite-oxidizing bacteria, and eukaryote cell types. The microbial transition had a simple profile and showed clear relation to nitrogen ions transition. Nitrosomonas and Nitrobacter were mainly detected during and oxidation, respectively. These results revealing representative microorganisms acting in each ammonification and nitrification stages will be valuable for the development of artificial simple microbial consortia for organic hydroponics that consisted of identified heterotrophs and autotrophic nitrifying bacteria.

Organic hydroponics induces systemic resistance against the air-borne pathogen, Botrytis cinerea (gray mould)

Here, we propose that organic hydroponics trigger induced systemic resistance (ISR) in lettuce against air-borne Botrytis cinerea, which causes gray mold. We compared effects of organic and chemical hydroponics, assessed presence of ISR elicitors in the hydroponic nutrient solution, and investigated molecular mechanism of ISR. Organic hydroponics significantly reduced gray mold lesions in lettuce (cultivated hydroponically) and cucumber (cultivated in soil and foliar sprayed with nutrient solution). The 1-aminocyclopropane-1-carboxylic acid synthase gene in lettuce and lipoxygenase and ethylene receptor-related gene in cucumber showed heightened expression, suggesting that the jasmonic acid/ethylene (JA/ET)-signaling pathway was involved in ISR for both crops. Low salicylic acid β-glucoside levels confirmed role of the ISR signaling pathway. ISR in both lettuce and cucumbers indicated that elicitors in organic hydroponics were nonhost-specific and that the JA/ET pathway was activated without microbe–root interaction. Thus, organic hydroponics can be an effective method for both soil-borne and air-borne disease control.

Suppression of Ralstonia solanacearum bacterial wilt disease by an organic hydroponic system

An organic hydroponic system that we developed has potential to control root diseases including bacterial wilt of hydroponically grown tomato. In inoculation tests with Ralstonia solanacearum during tomato plant cultivation in conventional inorganic hydroponics and in our organic system, many of the tomato seedlings in the conventional system wilted and died, but none of the seedlings in the organic hydroponics wilted or developed any symptoms, suggesting that the organic system can suppress this bacterial wilt disease. Interestingly, a rhizosphere biofilm, formed only on roots in the organic hydroponic system, may be responsible for the suppression of the bacterial wilt.

Microbial mineralization of organic nitrogen into nitrate to allow the use of organic fertilizer in hydroponics

Hydroponics is an excellent technique for the cultivation of vegetable crops and other plants, but organic fertilizers cannot be used in conventional hydroponic systems, which generally use only inorganic fertilizers, because organic compounds in the hydroponic solutions generally have phytotoxic effects that lead to poor plant growth. Few microorganisms are present in hydroponic solutions to mineralize the organic compounds into inorganic nutrients. In this article a novel and practical hydroponic culture method that uses microorganisms to degrade organic fertilizer in the hydroponic solution has been developed. Soil microorganisms were cultured by regulating the amounts of organic fertilizer and inoculum, with moderate aeration. The microorganisms mineralized organic nitrogen via ammonification and nitrification into nitrate at an efficiency of 97.6%. The culture solution containing the microorganisms was usable as a hydroponic solution, and organic fertilizer could be directly added to it during vegetable cultivation. Vegetables grew well in the organic hydroponic system. Organic hydroponics based on this method is therefore a practical tool for the utilization of organic sources of fertilizer.

Microbial ecosystem constructed in water for successful organic hydroponics

AbstractConventional hydroponics systems generally use only chemical fertilisers, not organic ones, since there are no microbial ecosystems present in such systems to mineralise organic compounds to inorganic nutrients. Addition of organic compounds to the hydroponic solution generally has phytotoxic effects and causes poor plant growth. We developed a novel hydroponic culture method using organic fertiliser. A microbial ecosystem was constructed in hydroponic solution by regulating the amounts of organic fertiliser and soil, with moderate aeration. The microbial ecosystem mineralised organic nitrogen to nitrate-nitrogen via ammonification and nitrification. A 97.6% efficiency of nitrate-nitrogen generation from the organic nitrogen in the organic fertiliser was achieved. The culture solution containing the microbial ecosystem was usable as a hydroponic solution. Vegetable plants grew well in our organic hydroponics system under continuous addition of organic fertiliser, and the yield and quality approximated those of vegetables grown by conventional hydroponics.