Hydroponic Medium Research Articles

Genome-wide association study reveals effect of nsSNPs on candidate genes in rice during iron deficiency.

Resource-poor areas with moisture deficit lands following aerobic and direct seeded rice (DSR) methods of cultivation face severe problems of iron deficiency. In this study, Bengal and Assam Aus rice panel was phenotyped at the seedling stage using an iron-deprived hydroponic medium for various shoot and root traits. A novel iron deficiency scoring scale was used to classify the tolerance reaction and could range anywhere between 0 and 9, indicating the most tolerant and susceptible, respectively. The GWAS results identified four putative candidate genes; OsFLA for number of leaves and shoot length, OsBIDK1 for root traits; average diameter, volume, biomass, projected area, and surface area, OsHPL3 for chlorophyll index of the third leaf and AKR2B (XBOS252) was for Fe score, (which was earlier reported in relation to Xa21). The nsSNP (nsSNPs) variations in these gene sequences were used to group the panel and identify superior haplotypes and donors. BR16 was identified as a superior donor, with higher chlorophyll index and shoot length than RA23, also higher values for root traits like root average diameter, root volume, root projected area and root surface area followed by Shete Bhado. The impact of identified nsSNPs on protein structure and stability was investigated. The conserved domains detected in the mutated proteins of the superior haplotypes are very informative, highlighting that natural selection favors abiotic stress tolerant variants in resource poor areas. Thus, justifying our choice of Aus landraces for association mapping of Fe deficiency tolerant genes in rice.

Effects of the co-exposure of microplastic/nanoplastic and heavy metal on plants: Using CiteSpace, meta-analysis, and machine learning

Micro/nanoplastics (MNPs) and heavy metals (HMs) coexist worldwide. Existing studies have reported different or even contradictory toxic effects of co-exposure to MNPs and HMs on plants, which may be related to various influencing factors. In this study, existing publications were searched and analyzed using CiteSpace, meta-analysis, and machine learning. CiteSpace analysis showed that this research field was still in the nascent stage, and hotspots in this field included accumulation, cadmium (Cd), growth, and combined toxicity. Meta-analysis revealed the differential association of seven influencing factors (MNP size, pollutant treatment duration, cultivation media, plant species, MNP type, HM concentration, and MNP concentration) and 8 physiological parameters receiving the most attention. Co-exposure of the two contaminants had stronger toxic effects than HM treatment alone, and phytotoxicity was generally enhanced with increasing concentrations and longer exposure durations, especially when using nanoparticles, hydroponic medium, dicotyledons producing stronger toxic effects than microplastics, soil-based medium, and monocotyledons. Dry and fresh weight analysis showed that co-exposure to MNPs and Cd resulted in significant phytotoxicity in all classifications. Concerning the MNP types, polyolefins partially attenuated plant toxicity, but both modified polystyrene (PS) and biodegradable polymers exacerbated joint phytotoxicity. Finally, machine learning was used to fit and predict plant HM concentrations, showing five classifications with an accuracy over 80 %, implying that the polynomial regression model could be used to predict HM content in plants under complex pollution conditions. Overall, this study identifies current knowledge gaps and provides guidance for future research.

Influence of light intensity on the responses of seedlings of neotropical tree species to nitrogen source

Light intensity plays a crucial role in N uptake and assimilation in plants, but its interaction with different N sources is overlooked. Considering the high energy required for N assimilation, it is hypothesised that low light is critical for the seedling development with both N sources, but with increased light intensity, growing with nitrate (NO3-) becomes favourable in relation to ammonium (NH4+). Seedlings of Cecropia pachystachya (pioneer), Guarea kunthiana (shade-tolerant, understory) and Cariniana estrellensis (shade-tolerant, canopy) were grown in hydroponic medium with NO3- or NH4+ as the sole N source and subjected to low (LL) or high light (HL) for 60 days. All three species showed a decrease in growth when cultivated with NH4+, compared to NO3-, under HL, but not under LL. The decrease in biomass reached 54% in C. pachystachya, 36% in G. kunthiana and 26% in C. estrellensis. Growth reduction was associated with stomatal limitation of photosynthesis and reduced leaf area in C. pachystachya, and with non-stomatal limitation of photosynthesis and oxidative stress in G. kunthiana. Cation uptake was negatively affected by NH4+ in all species. Cariniana estrellensis showed no photosynthetic limitation and showed a higher tolerance to NH4+ under HL in terms of nutrient content. In conclusion, neither N source significantly favors seedling development under LL, while NH4+ is considerably more unfavorable for seedling development than NO3- under HL.

Performance Evaluation of Hydroponic Grow-Outs in An Innovative Coldwater Aquaponic System Featuring Rainbow Trout and Lettuce

A 45-day trial was carried out to assess the production performance of different hydroponic media in a novel do-it-yourself (DIY) low-tech re-circulating aquaponic system for temperate regions with rainbow trout (Oncorhynchus mykiss) and lettuce (Lactuca sativa). Rainbow trout juveniles (average weight of 35.59 g) were stocked in the experimental units at 2.8 kg.m-3 and fed with commercial floating pelleted feed at 8 % of their body weight in three treatments and a control. The lettuce saplings were randomly planted in the river stone bed (T1), crushed stone bed (T2), raft/deep water culture (DWC) unit (T3) and control (C) soil bed (fortified with NPK fertiliser) with equivalent planting intervals of 42 saplings.m-2. The system, designed with low-tech simplicity, was managed without alkalinity correction and depended entirely on plant growth and metabolism for biofiltration. The water quality parameters such as temperature, pH, dissolved oxygen (DO), dissolved free CO2, hardness, total alkalinity, ammonium, nitrite, and nitrate varied significantly (P < 0.05) among the treatments compared to the control. The final individual weight, biomass gain, specific growth rate (SGR), and feed conversion ratio (FCR) of rainbow trout were significantly better (P < 0.05) in media beds (crushed stone and river stone) compared to control and DWC systems. The final mean weights of rainbow trout in river stone (12.33 ± 0.002 g and crushed stone (12.39 ± 0.054 g) treatments were significantly higher (P < 0.05) than in DWC (12.1 ± 0.023 g) and control (12.09 ± 0.002 g) treatments. The production of lettuce was significantly greater (P < 0.05) in all three treatments (river stone: 4.33 ± 0.123 g, crushed stone: 4.53 ± 0.09 g and DWC: 4.31 ± 0.163 g) compared to the control (3.31 ± 0.172 g). The DWC including the media bed systems facilitates the improved performance of lettuce saplings in terms of final height and leaf number. These results show that a low-tech media bed system without a supplementary biofiltration unit can achieve sustainable production of both fish and vegetables in temperate hilly terrains.

GC–MS metabolomics of French lettuce (Lactuca Sativa L. var capitata) leaves exposed to bisphenol A via the hydroponic media

IntroductionBisphenol A (BPA), an organic compound used to produce polycarbonate plastics and epoxy resins, has become a ubiquitous contaminant due to its high-volume production and constant release to the environment. Plant metabolomics can trace the stress effects induced by environmental contaminants to the variation of specific metabolites, making it an alternative way to study pollutants toxicity to plants. Nevertheless, there is an important knowledge gap in metabolomics applications in this area.ObjectiveEvaluate the influence of BPA in French lettuce (Lactuca Sativa L. var capitata) leaves metabolic profile by gas chromatography coupled to mass spectrometry (GC–MS) using a hydroponic system.MethodsLettuces were cultivated in the laboratory to minimize biological variation and were analyzed 55 days after sowing (considered the plant’s adult stage). Hexanoic and methanolic extracts with and without derivatization were prepared for each sample and analyzed by GC–MS.ResultsThe highest number of metabolites was obtained from the hexanoic extract, followed by the derivatized methanolic extract. Although no physical differences were observed between control and contaminated lettuce leaves, the multivariate analysis determined a statistically significant difference between their metabolic profiles. Pathway analysis of the most affected metabolites showed that galactose metabolism, starch and fructose metabolism and steroid biosynthesis were significantly affected by BPA exposure.ConclusionsThe preparation of different extracts from the same sample permitted the determination of metabolites with different physicochemical properties. BPA alters the leaves energy and membrane metabolism, plant growth could be affected at higher concentrations and exposition times.

Analysis of the Ability of Marsh Samphire (Salicornia europaea) to Extract Environmentally Relevant Elements from Different Culture Media: Contribution of Biochar to Plant Nutrition and Growth

Soil salinity is considered one of the major global challenges that agricultural production is currently facing. This condition, together with the increasing contamination with emerging pollutants, poses a serious risk for global food security. As efforts are made to develop nature-based solutions, bioremediation strategies have been implemented to harness different living organisms and mitigate environmental pollution. Halophytes grow in highly saline environment and can be the solution to valorize salt-degraded areas where other crops cannot grow. The aim of this work is to evaluate the physiological response of Salicornia europaea grown under different conditions and its potential to extract sodium (Na) and copper (Cu) from different culture media. Different experiments were conducted with S. europaea cultivated in hydroponics and in substrate with and without biochar including different Cu (0, 5 and 10 mg L-1 CuCl2) and Na (7.5 and 15 g L-1 NaCl) concentrations. The growth in hydroponic media under different salinities reveals that this halophyte can extract up to 80% and 55% of the initial Na content when growing at 7.5 g L-1 and 15 g L-1 NaCl, respectively. In addition, S. europaea tolerates high Cu concentration, accumulating up to 1.61 mg g-1 DW in roots when exposed to 10 mg L-1 CuCl2 and 7.5 g L-1 NaCl. Plants grown in substrate show a different behavior, being even more tolerant to higher Cu concentrations. In addition, the presence of biochar in the substrate improves plant growth and provides a greater quantity of micronutrients. These results show the potential of S. europaea to be used in the phytoremediation process.

Growth response of mustard greens (Brassica juncea L.) to nutrient formulations in hydroponic media

Abstract The production of mustard greens (Brassica juncea L.) by applying a hydroponic technique has been widely operated in urban areas. One of limited factor on hydroponic operation is a high spending cost on nutrition input i.e. AB Mix nutrition. The aim of this research was to evaluate the effectiveness of NPK for substituting AB Mix on hydroponic operation of mustard greens. The research was conducted at BPTP Jakarta, from February to April 2021. Five combinations of NPK substitution on AB Mix were evaluated, namely: 100% AB Mix as control (H0), 75% AB Mix - 25% NPK (H1), 50% AB Mix - 50% NPK (H2), 25% AB Mix - 75% NPK (H3), 100% NPK (H4). All the treatments were arranged on a completely randomized design with 4 replications. The results showed that combination of AB Mix 25% + NPK 75% (H3) yield mustard greens growth similarly with the control plant (100% AB Mix). This finding approved that proportion of NPK for AB Mix substitution was appropriate up to 75% on hydroponic operation for mustard greens cultivation.

The effect of different levels of liquid organic compost of Chromolaena odorata on production, nutrient composition, and In Vitro digestibility of hydroponic maize fodder

The aims of the present study were to evaluate the addition of different levels of liquid organic compost of Chromolaena odorata (CO) in hydroponic media on production, nutrient composition, and in vitro digestibility of hydroponic maize fodder. Maize grains were obtained from the local market and grown hydroponically in the media. The study was design following a completely randomized design with 5 treatments and 4 replications. The treatments were: CR 0 = without liquid organic compost; and with liquid organic compost of 25 ml (CR 1); 50 ml (CR 2); 75 ml (CR 3); 100 ml (CR 4). The liquid organic compost of Chromolaena odorata used was fermented for 21 days before application into the fodder. Maize fodder was grown hydroponically for 7 days before being harvested. Data obtained from this study were analyzed using ANOVA of SPSS 25. Addition of liquid organic compost of Chromolaena odorata had a significant effect on increasing (P<0.05) fodder height, leaf length, leaf width, fresh weight, and dry weight. Similarly increasing the level of liquid organic compost of Chromolaena odorata significantly improved In vitro dry matter digestibility, organic matter digestibility, VFA, and NH3. However, there was no different between treatments (P>0.05) on root length. In conclusion, the addition of different levels of liquid organic compost of Chromolaena odorata increased maize production, nutrient composition and in vitro digestibility of hydroponic maize fodder.

From shower to table: fate of organic micropollutants in hydroponic systems for greywater treatment and lettuce cultivation

ABSTRACT This study evaluated the dual functionality of hydroponic systems to grow edible crops while treating greywater (GW) containing 20 organic micropollutants (OMPs). Various conditions with differing nutrient contents were tested: raw GW, GW with struvite, and GW with commercial nutrient solution. System performance was assessed with plant growth and standard parameters and OMP removal. After 4-week exposure, all conditions produced healthy-looking plants, proving GW as a viable hydroponic growth medium. However, only the condition with commercial solution yielded plants comparable to the biotic control, indicating the necessity of nutrient supplementation. Effluent from conditions with well-developed plants met the requirements of the European water reuse legislation (EU 2020/741) for scenarios B–D (food crops not in direct contact with the reclaimed water and industrial crops), and had the highest OMP removal, showcasing the effectiveness of the system for OMP treatment. Estimated calculations of OMP detected in leaves (10/20 OMP detected, predominantly positive and small) resulted in calculated potential human health risks through lettuce intake for two compounds: atenolol and epoxycarbamazepine. These findings support a continued evaluation of the behavior of other OMPs and their transformation products in water–plant systems, and their consideration in legislation on water reuse and food safety.

Overexpression of OsTIP1;2 confers arsenite tolerance in rice and reduces root-to-shoot translocation of arsenic

Tonoplast Intrinsic Proteins (TIPs) are vital in transporting water and solutes across vacuolar membrane. The role of TIPs in the arsenic stress response is largely undefined. Rice shows sensitivity to the arsenite [As[III]] stress and its accumulation at high concentrations in grains poses severe health hazards. In this study, functional characterization of OsTIP1;2 from Oryza sativa indica cultivar Pusa Basmati-1 (PB-1) was done under the As[III] stress. Overexpression of OsTIP1;2 in PB-1 rice conferred tolerance to As[III] treatment measured in terms of enhanced shoot growth, biomass, and shoot/root ratio of overexpression (OE) lines compared to the wild-type (WT) plants. Moreover, seed priming with the IRW100 yeast cells (deficient in vacuolar membrane As[III] transporter YCF1) expressing OsTIP1;2 further increased As[III] stress tolerance of both WT and OE plants. The dithizone assay showed that WT plants accumulated high arsenic in shoots, while OE lines accumulated more arsenic in roots than shoots thereby limiting the translocation of arsenic to shoot. The activity of enzymatic and non-enzymatic antioxidants also increased in the OE lines on exposure to As[III]. The tissue-specific localization showed OsTIP1;2 promoter activity in root and root hairs, indicating its possible root-specific function. After As[III] treatment in hydroponic medium, the arsenic translocation factor (TF) for WT was around 0.8, while that of OE lines was around 0.2. Moreover, the arsenic content in the grains of OE lines reduced significantly compared to WT plants.

Differential Physiological and Molecular Processes in the Root May Underlie Contrasting Salt Tolerance in Two Egyptian Rice Cultivars at the Seedling Stage

This study aimed to compare various responses of two Egyptian rice accessions bred for high yields, Sakha108 and Giza177, to salt stress at the seedling stage. Twenty-eight-day-old seedlings of two cultivars were grown in a hydroponic medium under control conditions (no NaCl) and salt stress (75 mM NaCl) for 12 days. Growth (dry weight), Na+ and K+ concentrations, enzymatic and non-enzymatic antioxidants, malondialdehyde (MDA), hydrogen peroxide (H2O2), and expression of Na+ and K+ transport-coding genes were recorded. Sakha108’s growth (18% rise from control) was significantly higher than Giza177’s. Both cultivars accumulated similar amounts of Na+ in the leaves and sheaths, however, Sakha108 had higher Na+ concentrations in the roots than Giza177 (13.3% higher). Root K+ concentration dropped dramatically (~ 2-fold reduction) in Giza177 roots while remaining unchanged in Sakha108 roots. The concentrations of H2O2 (root) and MDA (leaf and root) were higher in Giza177 than in Sakha108, although the difference was not statistically significant. Proline and total flavonoid (TF) contents in Sakha108 roots were greater than those in Giza177 roots. The expression of OsHKT1;5 and OsHKT2;1 genes declined in both cultivars, whereas expressions of OsSOS1, OsNHX1, and OsHAK7 were induced in Sakha108 but, except for OsHAK7, were repressed in Giza177. Combined, these findings suggest that Sakha108 is more resistant to salt stress than Giza177 is, and that this variation in tolerance may have its origins in the root systems of the two cultivars. Thus, these adaptive traits in the root of Sakha 108 could be explored for engineering stress tolerance in susceptible but high-yielding rice cultivars.

Germination and stress tolerance of oats treated with pulsed electric field at different phases of seedling growth

This study explores the impact of pulsed electric field (PEF) application on oat seedling growth and stress tolerance. PEF treatment (99 monopolar, rectangular pulses lasting 10 µs each, with a frequency of 13 Hz and a nominal electric field strength of 2250 V/cm) was applied at two growth stages: (i) when the seedlings had 0.2 cm roots emerging from the kernel, and (ii) when they had a 0.4 cm shoot emerging from the kernel. Post-treatment, the seedlings were hydroponically grown for 8 days. To induce stress, the hydroponic medium was augmented with PEG (15 %) to induce drought stress and NaCl (150 mM) to induce salinity stress. Results demonstrate that applying PEF improved the growth of the root and shoot of oat seedlings. This effect was more pronounced when applied to more developed seedlings. When PEF was applied during the later stage of germination, seedlings exposed to salinity stress showed enhanced shoot growth compared to the control. Under the studied conditions, the application of PEF had no impact on the growth of seedlings under drought stress.

Budidaya tanaman hidroponik melalui pendampingan pemanfaatan limbah anorganik sebagai media tanam di sekolah

Hydroponic farming has emerged as an effective alternative to overcome land limitations, especially in urban and compact residential areas. Focusing on two Madrasah Aliyah in East Lombok, the Community Service Program by the Biology Education Department of Universitas Hamzanwadi implemented hydroponic techniques as an innovative farming method. This initiative aimed to enhance environmental awareness and farming skills among students, while utilizing styrofoam waste as a planting medium. The process included socialization, seedling production, planting, maintenance, and harvesting, using plants such as water spinach, lettuce, and spinach. The implementation method incorporated Participatory Rural Appraisal (PRA), enabling active participation from students and teachers. The program was conducted from March to November 2023 at MA NWDI Juet and MA Ridlol Walidain NW Batu Bangka - Jenggik. The mentoring process involved various stages, from introducing hydroponic techniques to creating planting media and planting, including the use of AB Mix nutrients and rockwool as planting media. The results of the activity showed successful cultivation of hydroponic water spinach, while lettuce and spinach experienced crop failure. The primary causes of this failure were inadequate care, light, and temperature. Nevertheless, the activity successfully educated students on the importance of hydroponic agriculture and creative waste utilization, providing new insights into urban farming. In conclusion, the hydroponic approach can be an efficient solution for cultivating plants in limited spaces, offering educational and environmental benefits. This program also highlighted the potential of styrofoam waste as a hydroponic planting medium, underscoring the importance of waste utilization for environmental sustainability.

Impact of Sodium Silicate Supplemented, IR-Treated Panax Ginseng on Extraction Optimization for Enhanced Anti-Tyrosinase and Antioxidant Activity: A Response Surface Methodology (RSM) Approach.

Ginseng has long been widely used for its therapeutic potential. In our current study, we investigated the impact of abiotic stress induced by infrared (IR) radiations and sodium silicate on the upregulation of antioxidant and anti-tyrosinase levels, as well as the total phenolic and total flavonoid contents of the Korean ginseng (Panax ginseng C.A. Meyer) variety Yeonpoong. The RSM-based design was used to optimize ultrasonic-assisted extraction time (1-3 h) and temperature (40-60 °C) for better anti-tyrosinase activity and improved antioxidant potential. The optimal extraction results were obtained with a one-hour extraction time, at a temperature of 40 °C, and with a 1.0 mM sodium silicate treatment. We recorded maximum anti-tyrosinase (53.69%) and antioxidant (40.39%) activities when RSM conditions were kept at 875.2 mg GAE/100 g TPC, and 3219.58 mg catechin/100 g. When 1.0 mM sodium silicate was added to the media and extracted at 40 °C for 1 h, the highest total ginsenoside content (368.09 mg/g) was recorded, with variations in individual ginsenosides. Ginsenosides Rb1, Rd, and F2 were significantly affected by extraction temperature, while Rb2 and Rc were influenced by the sodium silicate concentration. Moreover, ginsenoside F2 increased with the sodium silicate treatment, while the Rg3-S content decreased. Interestingly, higher temperatures favored greater ginsenoside diversity while sodium silicate impacted PPD-type ginsenosides. It was observed that the actual experimental values closely matched the predicted values, and this agreement was statistically significant at a 95% confidence level. Our findings suggest that the application of IR irradiation in hydroponic systems can help to improve the quality of ginseng sprouts when supplemented with sodium silicate in hydroponic media. Optimized extraction conditions using ultrasonication can be helpful in improving antioxidant and anti-tyrosinase activity.

Control System Design for Water Pump Activation in PLC-based Smart Hydroponic Design

Food security is one of the issues that is one of the concerns to the country government, and one of the independent efforts made by community on their awareness to meet and achieve food needs on a domestic scale in their respective households is through hydroponic for cultivation of vegetables. Hydroponics works by using water as growing medium instead of soil, however, the use of water as a planting medium requires special treatment thus the plants is able to grow optimally. To ensure that the air content in the water used as a hydroponic growing medium is properly available, a water regulation process is needed. The process of water regulation in the hydroponic system uses regulation of the activation of the water pump motor so that water can be regulated and electrical energy efficiency can still be achieved. This study aims to design and test a PLC-based automation system for the purposes of setting the activation of a water pump in a hydroponic system based on the sunlight conditions in the hydroponic installation being built. By using a light sensor (LDR) to measure the intensity of sunlight in the hydroponic system being built, the activation of the pump motor can be controlled through the use of a PLC device that processes the information obtained from the sensor used. The results of the tests carried out provide information that the designed system has proven effective for use in hydroponic systems with pump water regulation time from 08:00 AM to 04:00 PM.

Mycorrhizal fungus Serendipita indica-associated acid phosphatase rescues the phosphate nutrition with reduced arsenic uptake in the host plant under arsenic stress

Symbiotic interactions play a vital role in maintaining the phosphate (Pi) nutrient status of host plants and providing resilience during biotic and abiotic stresses. Serendipita indica, a mycorrhiza-like fungus, supports plant growth by transporting Pi to the plant. Despite the competitive behaviour of arsenate (AsV) with Pi, the association with S. indica promotes plant growth under arsenic (As) stress by reducing As bioavailability through adsorption, accumulation, and precipitation within the fungus. However, the capacity of S. indica to enhance Pi accumulation and utilization under As stress remains unexplored. Axenic studies revealed that As supply significantly reduces intracellular ACPase activity in S. indica, while extracellular ACPase remains unaffected. Further investigations using Native PAGE and gene expression studies confirmed that intracellular ACPase (isoform2) is sensitive to As, whereas extracellular ACPase (isoform1) is As-insensitive. Biochemical analysis showed that ACPase (isoform1) has a Km of 0.5977 µM and Vmax of 0.1945 Unit/min. In hydroponically cultured tomato seedlings, simultaneous inoculation of S. indica with As on the 14thday after seed germination led to hyper-colonization, increased root/shoot length, biomass, and induction of ACPase expression and secretion under As stress. Arsenic-treated S. indica colonized groups (13.33 µM As+Si and 26.67 µM As+Si) exhibited 8.28–19.14 and 1.71–3.45-fold activation of ACPase in both rhizospheric media and root samples, respectively, thereby enhancing Pi availability in the surrounding medium under As stress. Moreover, S. indica (13.33 µM As+Si and 26.67 µM As+Si) significantly improved Pi accumulation in roots by 7.26 and 9.46 times and in shoots by 4.36 and 8.85 times compared to the control. Additionally, S. indica induced the expression of SiPT under As stress, further improving Pi mobilization. Notably, fungal colonization also restricted As mobilization from the hydroponic medium to the shoot, with a higher amount of As (191.01 ppm As in the 26.67 µM As+Si group) accumulating in the plant's roots. The study demonstrates the performance of S. indica under As stress in enhancing Pi mobilization while limiting As uptake in the host plant. These findings provide the first evidence of the As-Pi interaction in the AM-like fungus S. indica, indicating reduced As uptake and regulation of PHO genes (ACPase and SiPT genes) to increase Pi acquisition. These data also lay the foundation for the rational use of S. indica in agricultural practices.

Sustainable Water Management: Developing a Hydroponic-Watering System to Support Epiphytic Plant Growth

This study introduces an innovative hydroponic–epiphytic water system designed to address water conservation challenges in urban agriculture. The system involves repurposing water from a hydroponic setup to irrigate epiphytic plants, promoting sustainability and efficient water management. Expert opinions on the system's development and innovations were gathered using a structured evaluation based on key indicators. Notably, the mean scores were analyzed using an Inter-rater reliability assessment in order to determine the expert's opinion on the development and innovations of the hydroponic-epiphytic water system, and indicate strong acceptance in various aspects, including economic profitability, low initial cost, and compatibility with social values. However, identified areas for modification, such as time and effort savings and immediate benefits, offer valuable insights for refinement. The hydroponic–epiphytic system's components, meticulously detailed in the study, contribute to its structural integrity and water circulation efficiency. The chemical composition of the hydroponic solution, emphasizing nitrogen-rich urea, ensures precise nutrient delivery. The hydroponic growing medium, a blend of carbonized rice hull and coconut coir, provides an optimal environment for plant growth. The closed-loop water flow system minimizes wastage by recycling hydroponic water for epiphytic plants, aligning with sustainable gardening practices. In conclusion, the hydroponic–epiphytic water system proves effective in meeting its objectives of innovation and water conservation. Expert evaluations enhance its credibility, and the identified areas for improvement offer a roadmap for optimization. Recommendations include exploring alternative energy sources, conducting extended studies for long-term observations, and a more comprehensive expert opinion study. This study contributes to the advancement of urban-friendly, sustainable water management practices in agriculture.

Metal accumulation and genetic adaptation of Oryza sativa to Cadmiun and Chromium heavy metal stress: A hydroponic and RAPD analyses

This research was performed to assess the influence of Cd and Cr metals on growth, pigments, antioxidant, and genomic stability of Oryza sativa indica and Oryza sativa japonica were investigated under hydroponic conditions. The results revealed that significant metal influence on test crop growth, pigment content, metal stress balancing antioxidant activity in a dose dependent manner. Since, while at elevated (500 ppm) concentration of Cd as well as Cr metals the pigment (total chlorophyll, chlorophyll a, b and carotenoids) level was reduced than control; however antioxidant activity (total antioxidant, H2O2, and NO) was considerably improved as protective mechanisms to combat the metal toxicity and support the plant growth. Furthermore, the test crops under typical hydroponic medium (loaded with Cd and Cr as 200, 300, 400, and 500 ppm) growth conditions, effectively absorb the metals from medium and accumulated in the root and least quantity was translocated to the shoot of this test crops. Furthermore, typical RAPD analysis with 10 universal primers demonstrated that the genomic DNA of the test crops was adaptable to develop metal resistance and ensure crop growth under increased concentrations (500 ppm) of tested heavy metals. These findings suggest that these edible crops have the ability to accumulate Cd along with Cr metals, and additionally that their genetic systems have the ability to adapt to metal-stressed environments.

Assessment of herbaceous ornamental plant species as potential remediation agents for cadmium contaminated environments

Industrial development has led to the pollution of lands with Cadmium (Cd), resulting in the contamination of edible crops and posing significant health risks to humans and animals. To address this issue, the selection of non-edible ornamental plants has been considered. In this study, a lab-scale experiment was conducted using five different ornamental plant species: Tabermaeontana divaricata L., Syngonium podophyllum Schott, Asparagus setaceus (Kunth) Jessop, Catharanthus roseus (L.) G. Don. and Portulaca grandiflora Hook. These plant species were treated 100 mL of 5 mg L−1 CdSO4 solution, continuing for 30 days in hydroponic medium with replenishment with same solution on every 3rd day. The main objective was to identify ornamental plant species with high tolerance and remarkable Cd translocation and accumulation power. The plants were evaluated based on their Tolerance Index (TI), Translocation factor (TF) and Bioaccumulation Factor (BAF) toward Cd in the hydroponic medium. P. grandiflora exhibited high tolerance to Cd with 95 % TI and S. podophyllum (TI – 85 %) and T. divaricata (TI – 62 %) showed limited tolerance while C. roseus and A. setaceus were found to be more sensitive. Moreover, Cd presence was also found to induce a hormetic response in P. grandiflora, T. divaricata, and S. podophyllum. Based on their TF and BAF values, P. grandiflora (TF-5.45; BAF-0.86) and S. podophyllum (TF-4.49; BAF-0.85) were identified as potential candidates for phytoextraction, while T. divaricata (TF-0.007; BAF-4.34) showed potential as a phytostabilizer of Cd. These findings propose for the utilization of these ornamental plants for the remediation of the Cd-contaminated soil and water, with the harvested biomass potentially serving as bio-ore for recovery of Cd.

New evidence of the arsenic uptake and translocation in As-hyperaccumulator fern Pteris cretica using a modified hydroponic system

Pteris cretica is a native fern in temperate regions known for its ability to hyperaccumulate arsenic (As). However, the uptake and translocation of As in hydroponic conditions have remained poorly understood. In this study, we modified a hydroponic cultivation system, combining 24 plants into one unit, to suppress individual differences among plants and evaluate As uptake and translocation in P. cretica. The 7-day short-term As removal experiment results revealed that the As uptake rate by P. cretica appears to be dependent on the initial As concentration in the hydroponic medium. Furthermore, the rhizomes play a role in regulating As translocation from roots to fronds in P. cretica was observed. In the 27-day long-term continuous flow experiment, approximately 1 mg/d of As was removed by P. cretica with 200 μg/L As applied. Moreover, the long-term translocation factor (TF) between rhizomes and roots and between fronds and rhizomes from the 27-day long-term continuous flow experiment demonstrated the same pattern as the short-term TF from the 7-day short-term As removal experiment, further indicating the role of rhizomes in regulating As translocation from roots to fronds in P. cretica.