Plant Irrigation Research Articles

Towards Water-Efficient Irrigation of Cup Plant (Silphium perfoliatum L.) for Energy Production: Water Requirements and Rainfall Deficit

Towards Water-Efficient Irrigation of Cup Plant (Silphium perfoliatum L.) for Energy Production: Water Requirements and Rainfall Deficit

Pengaruh Variasi Diameter Pipa Primer Terhadap Pola Resapan Air Irigasi tetes Bertingkat Pada Media Tanam Polybag

Multilevel drip irrigation is an irrigation method that supports water-saving agricultural activities in limited areas by channeling water through perforated pipes from emitters. The ideal multistage drip irrigation system can provide the same drip volume to plants, so the distribution of irrigation water and its depth need to be important factors to pay attention to in order to provide optimal plant irrigation. This research aims to determine the effect of using variations in primary channel pipe diameter on the distribution of drip irrigation and the depth of infiltration of irrigation products in a 3 (three) tier drip irrigation network. Tests were carried out on primary pipes from floors 1 to 3 with a diameter of ½", ¾" and pipes 1", with lateral drip pipes with ½" PVC. The size of the test field is 4 m x 1 m x 1.8 m and the distance between levels is around 0.9 m and the irrigation water source from a 200 liter tank is 2.5 m high. The research results showed that irrigation distribution results were quite good at all levels of the irrigation network, namely 70 ml and 68 ml. Irrigation patterns do not have a significant effect on the results of irrigation distribution due to variations in primary pipe diameter. A soil composition of 30% compost has achieved irrigation infiltration with a depth of 21 cm, including the fastest, namely 25 minutes and for 70% soil, an irrigation infiltration time of 35 minutes is required.

An Overview of Seed Production Methodologies in Selected Flowering Annuals

This review provides a comprehensive overview of flower seed production, emphasizing the significance of the floriculture industry. Flower crops, especially annuals, contribute significantly to the beautification of surroundings and have become a lucrative agricultural business globally. The demand for quality flower seeds has led to the establishment of production facilities, particularly in India, catering to both domestic and international markets. The climatic requirements for seed production vary across different flower crops, with considerations for mild, sub-tropical, and tropical climates. The review delves into the nature of pollination for various flower crops, emphasizing the need for isolation to prevent contamination. F1 hybrid seed production is discussed, highlighting its merits and demerits, along with techniques for creating cross-hybrid seeds. The agronomic principles involved in hybrid seed production, including variety selection, seed pre-conditioning, planting time, sowing methods, and density, are detailed. The role of plant growth regulators, irrigation, and nutrition in optimizing seed yields is explored. Harvesting methods and the critical importance of proper timing are addressed, along with insights into seed storage conditions. The review concludes by emphasizing the multifaceted aspects of flower seed production, from climatic considerations to agronomic practices, pollination, and post-harvest processes. The knowledge presented serves as a valuable resource for practitioners and researchers in the floriculture and seed production sectors.

Adaptation strategies for cumin in Sabzevar, Iran: planting date and irrigation management

ABSTRACT The current study aimed to investigate the effect of planting date and irrigation on some characteristics of cumin cultivated in Iran. The experimental characteristics included three planting dates and five irrigation regimes. Irrigation at flowering + seed filling stage and full irrigation had the highest essential oil content (3.6%) and plant height (16.71 cm), respectively. On all planting dates, irrigation enhanced the total chlorophyll and carotenoids content, relative water content, umbel number plant−1, seed number umbel−1, 1,000-seed weight, and seed yield but reduced the proline content and water-use efficiency (WUE). The highest chlorophyll content (1.54 mg g−1 fresh weight (FW)), carotenoids content (0.35 mg g−1 FW), umbel number plant−1 (18.03), seed number umbel−1 (21.16), 1,000-seed weight (4.12 g), seed yield (1002.7 kg ha−1), and essential oil yield (22.13 kg ha−1) were obtained on 19 January and irrigation at the flowering + seed filling stages. The greatest amount of WUE (0.53 kg m−3) was measured on 9 January under no irrigation condition. Therefore, to produce cumin under similar climatic conditions, early planting of cumin in early January, along with two irrigations at the flowering and seed filling stages, is recommended.

IoT based Automated Greenhouse

The advent of the greenhouse as a sustainable form of smart agricultural farming present a best solution to address the challenges like food scarcity resulting from population growth, climate change and environment change. This method help in off-season crop cultivation even in severe climatic conditions within enclosed spaces. However, effective control and management of crop parameters within the greenhouse are essential. Leveraging advancements in the Internet of Things (IoT) introduces smart solutions for automating greenhouse farming parameters including plant monitoring, atmosphere control, and irrigation. The greenhouse is one of the growing technologies used for cultivation. This work proposes study of technologies used in the greenhouse for monitoring and control. This work analyses the different communication techniques used for monitoring the parameter of greenhouse using relays, sensors. With the help of Wi-Fi connectivity helps to analyse the real data over the cloud, real time working of the equipment. The advantage over the simple greenhouse so that the farmer can easily understand which technology suit the best. This also help farmer to adopt the best suited technique in greenhouse that are cost-friendly, easy to use, and have longer life. Keywords – IoT, Greenhouse, NodeMCU, Firebase.

Effects of Climate Change Adaptation Strategies on Maize Productivity among Smallholder Farmers in Dodoma, Tanzania

This study sought to establish the impact of climate change adaptation strategies on maize productivity among smallholder farmers in Dodoma, Tanzania. Employing a cross-sectional research design, data was collected from 274 respondents who were randomly selected. A structured questionnaire was utilized for data collection, and the Propensity Score Matching (PSM) technique was employed to estimate the effects of climate adaptation strategies on maize productivity. The findings indicate that smallholder farmers who adopted climate change adaptation tactics achieved higher maize yields compared to non-adopters. Additionally, results from multiple linear regression demonstrate that increased maize yields are associated with the adoption of drought-resistant maize varieties, intercropping, minimal tillage, adjusted planting dates, fertilizers, irrigation and short-duration maize varieties. Notably, crop rotation showed no significant effect on maize productivity. Policy recommendations include government investment in promoting the adoption of climate change adaptation strategies among smallholder farmers to mitigate losses and improve the farmers’ well-being. Furthermore, investments in modern irrigation schemes and the use of drought-resilient seeds are deemed crucial for enhancing agricultural resilience in the face of climate change.

Grain-filling strategies of wheat of contrasting grain sizes under various planting patterns and irrigation levels

In a study comparing grain filling and yield in a large- and a small-grain-size wheat cultivar under two planting patterns and two irrigation regimes, plastic-covered ridge and furrow planting with sprinkler irrigation increased grain filling and yield in both cultivars. The largest contributors to grain yield were an extended active grain-filling period in Shuangda 1 and an increased mean grain-filling rate in XN538.

Seedbed management, transplanting methods and irrigation regimes influence the growth, productivity and economics of summer rice (Oryza sativa L.)

A field experiment was conducted during the rabi (winter) seasons of 2017–2018 and 2018–2019 at the Central Research Farm under Bidhan Chandra Krishi Viswavidyalaya, West Bengal, India, to study the effects of planting techniques, irrigation regimes, and nursery bed management on the growth, yield, nutrient dynamics, water productivity, and economics of summer rice (cv. Shatabdi) production. The experiment was performed in a strip-split plot design with twelve treatment combinations, which were replicated three times. The design consisted of two types of transplanted rice establishment methods (viz., puddled transplanted rice (PTR) and nonpuddled transplanted rice (NPTR)) allocated to the main plot, three irrigation regimes (three-day intervals; six-day intervals; nine-day intervals) allocated to the subplot, and two nursery bed management practices (conventional seedbed and improved seedbed) allocated to the subplot. Higher growth attributes, such as plant height, tiller count, biomass, and LAI, were found under nonpuddled conditions at the time of harvesting. Similarly, a three-day irrigation interval and improved seedlings led to better growth traits. The yield attributes and yield varied nonsignificantly among the crop establishment methods. However, the lowest irrigation intervals accounted for 53.78% and 43.02% greater grain yield than did the nine-day intervals in two consecutive years, respectively, and produced statistically similar yields with six-day intervals. The percentage of seedlings transplanted from improved seedbeds was 4.01 and 4.13% greater than that from conventional seedlings. A similar trend was observed for both input and irrigation water productivity, except that the nine-day irrigation interval resulted in significantly greater water productivity than did the other intervals. The treatment consisted of nonpuddled transplanted rice along with six six-day irrigation intervals and improved seedbed management, resulting in the highest net return and benefit:cost ratio due to the low production cost. Thus, it can be concluded that transplanting seedlings into nonpuddled soil from an improved seedbed with intermittent irrigation might be the most judicious and recommended in terms of productivity as well as profitability for summer rice production.

Automatic Water Pumping System for Smart Greenhouse Using Renewable Energy Resources

This paper proposes an automatic water pumping system for a smart greenhouse, optimizing plant irrigation using renewable energy. It features sensors monitoring soil moisture, a pump powered by solar or wind, and a control unit adjusting pump operation based on sensor readings. The system, linked to the Internet, enables remote monitoring and control. Expected benefits include reduced manual watering, decreased reliance on non-renewable energy, and enhanced greenhouse efficiency. Smart greenhouses aim to enhance plant cultivation sustainability, with a crucial role played by the automated irrigation system, comprising a control unit, pump, and moisture sensors. Internet connectivity facilitates remote monitoring and adjustment for informed greenhouse operation.

Investigation of the indoor CO2 removal efficiency and fresh air energy savings of living walls in office spaces

Elevated indoor CO2 levels might have adverse effects on human health. However, conventional physical and chemical methods for indoor CO2 removal face the challenges of high energy consumption, low efficiency at low CO2 concentrations, and high costs. Furthermore, the introduction of outdoor air to lower indoor CO2 concentrations results in significant HVAC energy consumption. Aligning with office hours and the natural light cycle, the utilization of photosynthesis in living walls (LWs) offers an energy-efficient and sustainable solution for the mitigation of high CO2 levels in office spaces. This study experimentally investigates the impacts of the carbon fixation pathways, light flux density, and substrate moisture content on the CO2 removal rate of LWs in two identical rooms. The findings provide practical suggestions for plant species selection, lighting design, and irrigation management in office spaces to enhance the CO2 removal efficiency of LWs. Additionally, the fresh air energy-saving effects of LWs under different scenarios are accurately simulated in EnergyPlus. The results demonstrate that choosing C3 plants over CAM plants in LWs yields higher CO2 removal efficiency. The activation of artificial lighting is recommended when the surface light flux density of LWs drops below the light compensation point (LCP), ensuring favorable conditions for growth. In a 30-m2 office room accommodating two and three occupants, LWs can respectively reduce the demand for fresh air by 13.9 %–38.5 % and decrease fresh air energy consumption by 11.2 %–28.2 %.

Growth, phytochemical concentration, nutrient uptake, and water consumption of butterhead lettuce in response to hydroponic system design and growing season

Two hydroponic system designs (nutrient film technique: NFT, and deep water culture: DWC) were set up in a climate-controlled greenhouse to compare growth, nutrients and water uptake patterns, yield and quality of lettuce (Lactuca sativa cv. Butterhead) during fall (October through November) and summer (July-August) growing conditions. The research was conducted with four system replicates for each hydroponic design and each system contained nine lettuce plants. Plant photosynthetic properties, growth parameters, and irrigation solution nutrient concentrations were measured weekly. At the end of the production cycle, plants were harvested for leaf area, fresh and dry yield of shoots and roots, nutritional and phytochemical concentrations. In the study, DWC system had better water quality properties than NFT including less seasonal water temperature fluctuation, which supported lettuce with better photosynthetic rates, growth rate and fresh yield in fall. Tipburn symptoms were only observed in summer, and NFT grown lettuce had significantly lower shoot calcium and magnesium concentrations than DWC in both fall and summer seasons, which led to more severe tip burn symptom in summer. In addition, better water quality in DWC also benefited lettuce with higher antioxidant concentrations than NFT, which included 9.4 % higher vitamin C in fall, 34.6 % higher total carotenoids in fall, 40.6 % higher non-acidified phenols in fall, as well as 12.9 % higher total chlorophyll in summer. Although there were marginal differences in fresh yield, most types of mineral nutrients and antioxidants between DWC and NFT, DWC performed better than NFT with less tipburn in summer as well as increased yield, total carotenoids, vitamin C and non-acidified phenols in fall.

Fungal Consortia Mediated Bio-Treatment of Organic Matter and Metals Uptake from Sewage Water: Maize Agro-Physiological Assessment

The present investigation aims to improve the efficiency of fungal mono- and mixed cultures in removing organic pollutants and metals from sewage water (SW) for further maize plant response assessments. The reduction in the organic load from the SW was harnessed using a co-culture consortium consisting of Aspergillus niger (KB5), Sordariomycetes sp. (D10), and Coniochaetaceae sp. (LB3). The testing results had evinced removal of up to 88% of the organic matter and more than 96%, 91%, 80%, and 47.6%, of removal percentages for Copper (Cu), Nickel (Ni), Cadmium (Cd), and Lead (Pb), respectively, with the developed fungal consortium [KB5 + D10 + LB3]. After treatment and lab experiments, a reuse of treated and untreated SW for plant irrigation was evaluated towards improving maize plant growth. Irrigation was conducted in pot experiments with three types of water: clean water (Control), untreated (USW), and treated SW by fungal consortia (TSW) and by station treatment plant STP (TSWP) using the randomized complete block (RCB) experimental design. Results of the pots trial revealed that the morphological parameters of SW-irrigated plants are slightly improved compared to water-irrigated plants. Data regarding assimilating area attributes indicated that the most significant enlargement of the assimilation area was observed with TSW-D (1/4) irrigation by 1051 cm2, followed by TSWP-D (0) by 953.96 cm2, then USW-D (1/4) by 716.54 cm2, as compared to plants irrigated with clean water (506.91 cm2). On average, the assimilation areas were larger by 51.76%, 46.86%, and 29.25% in TSW, USW, and TSWP-irrigated plants, respectively. Thus, SW irrigation supports the required qualities and quantities of microelements and water for plant growth. Oxidative stress assessment showed that irrigations with treated SW caused a significant decrease in both enzymatic and non-enzymatic antioxidants, depicting that the treatment lowered the stress of sewage water.

Waste Utilization in Horticulture: An Overview

Waste management in horticulture plays a pivotal role in achieving environmental sustainability and optimizing resource utilization. One of the primary methods for waste utilization is composting, which involves the decomposition of organic waste materials to produce nutrient-rich compost. Compost serves as an excellent soil amendment, enhancing soil fertility and promoting plant growth. Additionally, anaerobic digestion offers a valuable approach for converting organic waste into biogas, a renewable energy source that can be used for heating, electricity generation, and vehicle fuel. Furthermore, fermentation processes can be employed to convert fruit and vegetable waste into valuable products such as animal feed and biofuels. The by-products of fermentation, including yeast and enzymes, have applications in various industries, contributing to the circular economy model. Advancements in precision agriculture and smart waste management systems have revolutionized waste utilization in horticulture. Technologies such as GPS, GIS mapping, wireless sensor networks and big data analytics enable data-driven, decision-making and optimize resource allocation. Precision planting, targeted spraying, automated pruning/harvesting and variable rate irrigation are among the innovative practices facilitated by these technologies, leading to increased productivity and efficiency in horticultural operations. Moreover, waste utilization in horticulture contributes to mitigating environmental pollution and reducing greenhouse gas emissions. By diverting organic waste from landfills and incineration, the emission of methane, a potent greenhouse gas, is minimized. Instead, organic waste is repurposed into valuable resources, thereby closing the loop on waste streams and promoting a circular economy.

A Raspberry Pi-Powered IoT Smart Farming System for Efficient Water Irrigation and Crop Monitoring

Water irrigation remain as a challenge to supply adequate amount of water to sustain the growth of plant and crops yield along the year in certain part of the world which are heavily affected by climate change. This scenario creates a huge risk toward the world food supply chain. Hence, the application of smart farming system is crucially important now to pave the way for a better the agriculture monitoring system to replace traditional manual monitoring labour by farmers. The smart farming system are usually equipped with environmental stimuli sensing system such as temperature, humidity, soil moisture, light intensity sensing sensors coupled with automation actuators to control the water irrigation rate for the crops in order to save water and at the same time provide adequate water supply for plant growth. The aim of using such smart farming system is to enable higher crops production and less human labour at the same time optimising resources available to minimize cost of farming. Hence, this paper aims to introduce a novel approach of a Raspberry Pi powered IoT smart farming system (ISFS) which can incorporate autonomous monitoring of plant irrigation, temperature, humidity, soil moisture and light intensity, to design a smartphone app that allows users to monitor plantation-related conditions in a user-friendly manner, and to enable automatic control of a drip irrigation system for plants based on data obtained on soil moisture, temperature and sunlight intensity. The proposed prototype with the functionality mentioned is aim to resolve the existing problem and to meet the demand of smart farming application in current era.

A Targeted and an Untargeted Metabolomics Approach to Study the Phytochemicals of Tomato Cultivars Grown Under Different Salinity Conditions.

In this study, we evaluated the effect of increasing the salinity of irrigation water on the metabolic content and profiles of two tomato cultivars ('Jaune Flamme' (JF) and 'Red Pear' (RP)) using targeted and untargeted metabolomics approaches. Irrigation of tomato plants was performed with four different salt concentrations provided by chloride (treatment 1) and sulfate (treatment 2) salts. Targeted analysis of the methanolic extract resulted in the identification of nine major polyphenols. Among them, chlorogenic acid, rutin, and naringenin were the prominent compounds in both cultivars. In addition, the quantification of 18 free amino acids from both tomato cultivars showed that different salinity treatments significantly enhanced the levels of glutamine, glutamic acid, and γ-aminobutyric acid (GABA). Using the untargeted metabolomic approach, we identified 129 putative metabolites encompassing a diverse array of phytochemicals including polyphenols, organic acids, lipids, sugars, and amino acids. Principal component analysis (PCA) of mass spectral data acquired under positive and negative ionization modes showed a clear separation between the two cultivars. However, only positive ionization showed separation among different salinity treatments. Unsupervised and supervised learning algorithms were applied to mine the generated data and to pinpoint metabolites different from the two cultivars. These findings suggest that different salinity conditions significantly influenced the accumulation of phytochemicals in tomato cultivars. This study will help tomato breeding programs to develop value-added tomato cultivars under varying environmental conditions.

Improved hydrological modelling and ET estimation in watershed with irrigation interference

Evapotranspiration (ET) is the true water consumption of the watershed and is key to achieving water conservation. The accurate estimation of ET by distributed hydrological model can provide an important basis for watershed water resources management. At present, the traditional approach calibrating distributed hydrological model parameters by runoff has low accuracy in watersheds under human interference. The reason is that the measured runoff is no longer natural due to various human activities such as river water withdrawals, reservoir regulation and inter-basin water transfer. While using ET for model calibration can effectively overcome this interference, making it a more accurate approach for watersheds under human interference. Therefore, we calibrated the Soil and Water Assessment Tool (SWAT) model using PMLV_2 ET in Ziya River under frequent human activities. The results indicated that calibrating the model with remote sensing ET could improve the model’s simulation performance, increasing the NS from 0.65 to 0.83. However, the annual ET calculated by the model was 21.7% lower than PMLV_2 ET. The largest underestimation was for the annual ET of cropland (agricultural ET), which was underestimated by 24.4%. This is partly because the model did not account for irrigation evaporation from cropland. Therefore we used Landsat 8 data to extract the planting areas of winter wheat, which consumes the highest irrigation water in the Ziya River Basin, from 2013 to 2018. The planting areas and irrigation regimes of winter wheat were incorporated into the SWAT model to calculate the agricultural ET. The results indicate that the agricultural ET calculated by the SWAT model that considers irrigation evaporation is 6.9% lower than that of PMLV_2 ET. The simulation accuracy of ET is significantly improved. This study provides a reference for accurate estimation of agricultural ET and a basis for ET management.

Optimizing crop planning in the winter fallow season using residual soil nutrients and irrigation water allocation in India

Effective management of water resources is essential for crop diversification and food security. This study proposes an Irrigation-Food-Environment-Chance-constrained Programming (IFEC) model for simultaneously optimizing crop planting area, irrigation water, and residual fertilizer considering inflow uncertainty along with farmer preference crop. Eight irrigation water allocation optimal models were constructed, fixing the preference crop cultivation area, while deviations in downstream release, and vegetable crop area cultivation were executed for sensitivity analysis. Model is then applied in a command area fed by a sub-tributary of Brahmaputra, India. On averaging, plant available N and P for the area were 62.14 kg ha−1 and 1.13 kg ha−1 respectively. With variation in available water, changes would occur in vegetable and cereal crops having higher yield and relatively less crop water requirement as compared to maize. Results showed that complying with preference crop area up to 60% would decrease the profit by 49% as compared to 20% at even 10% risk probability for 70% release. At existing conditions, water would be insufficient at 60% preference crop. Further, R2 value between benefit and water availability for vegetable cultivation varies from 0.99 to 0.78 for all scenarios. The tool featured that, setting specific preference crop areas provides equitable situation rather than mono-cropping. From the study findings, we suggest two salient recommendations: (1) promoting policies with appropriate financial subsidies for vegetable cultivation that focus on intensification with less water-requiring crops and (2) optimization results could be achieved by expanding the water utilization in the present condition while increasing efficiency.

Common agronomic adaptation strategies to climate change may increase soil greenhouse gas emission in Northern Europe

Climate change poses a significant threat to agriculture, highlighting the need for adaptation strategies to reduce its impacts. Agronomic adaptation strategies, such as changes in planting dates, fertilization, and irrigation, might sustain crop yield. However, their impact on soil greenhouse gas (GHG) emission is unknown under future climate scenarios. Using the LandscapeDNDC model, we assessed the effect of agronomic adaptation strategies (early sowing, increased fertilization dose, and increased irrigation amount) on soil GHG emission, yield, and yield-scaled GHG emission. A diversified crop rotation (potato – winter wheat – spring barley – faba bean) of a long-term experiment in Denmark was used for model validation. The adaptation practices to climate change were implemented for two representative concentration pathways (RCPs; 4.5 and 8.5) and five coupled global circulation and regional climate models. The adaptation scenarios were contrasted against a baseline scenario under current management practices. Soil-related variables showed better model fit (refined index of agreement ≥ 0.38) and lower errors (mean absolute error ≤ 8.18) than crop-based outputs for model validation. A total yield of ∼29 (± 3) t DW ha−1, and soil GHG emission of ∼3.02 (± 1.39) t CO2e ha−1 (RCP8.5) were obtained for the crop rotation system under the baseline for 2071–2100. Early sowing and its combination with increased fertilization decreased the yield compared to the baseline by 6.1 and 4.8 %, respectively (RCP8.5). Conversely, early sowing with increased irrigation, and early sowing with increased fertilization and irrigation, produced higher yields by 2.3 and 4.0 %, respectively (RCP8.5). All the agronomic adaptation strategies increased soil GHG emissions (ranging from 4.1 to 17.8 %) as well as yield-scaled GHG emissions (varying from 3.0 to 12.9 %) (RCP8.5). The highest soil GHG emission was simulated for early sowing in combination with increased fertilization and irrigation. Our study indicates that soil GHG emission will increase in the coming decades and that the agronomic adaptation strategies needed to sustain food production may further exacerbate this emission.

Experimental accumulation and depuration kinetics and natural occurrence of microcystin-LR in basil (Ocimum basilicum L.)

Microcystin-LR (MC-LR) is a hepatotoxic metabolite that naturally occurs during some cyanobacterial blooms in eutrophic waterbodies, and irrigation of edible plants with MC-LR-contaminated water causes bioaccumulation of the toxin. However, sufficient information about accumulation and depuration mechanics in hydroculture-grown herb plants is still lacking. This work aimed at 1) investigating bioaccumulation and depuration of MC-LR in basil, 2) verifying the possible MC-LR detoxification mechanisms in the plant, and 3) detecting the natural occurrence of MC-LR in basil (n = 50) collected from the Belgian market. Basil plants grown in a hydroculture were exposed to MC-LR (5, 20, and 50 μg L−1) spiked in a Hoagland solution for seven days. MC-LR depuration was also studied by transferring the plants to a non-contaminated Hoagland solution after exposure to MC-LR for another seven days. MC-LR concentrations in Hoagland solution, basil leaves, and roots were quantified using a validated UHPLC–MS/MS method. In addition, ELISA and LC–HRMS (only basil leaves) were used for confirmation. The results showed an increase in the accumulated levels of MC-LR at higher exposure doses, with higher MC-LR levels in roots than in leaves for all the treatment conditions. For MC-LR depuration, significant reductions were observed in all the treatment conditions for roots only. No MC-LR conjugates, potentially related to metabolism, were detected by LC–HRMS. Finally, MC-LR was detected in one store-bought basil sample, representing the first occurrence of cyanotoxins in an edible crop from Belgium.

Accumulation of phytotoxic metals and metalloids in vegetable continuum subjected to different irrigation streams: a threat towards nutritional security

The urban agro-ecosystem in developing countries plays a major role in uplifting the socioeconomic status of their inhabitants by confronting the challenges of improving food security and eradicating hunger. Food security and safety has become a serious global concern owing to accumulation of phytotoxic metals and metalloids in different food commodities subjected to different contaminated irrigation sources. The current study was undertaken to assess the concentrations of heavy metals and metalloid in ridge gourd (Luffa cylindrica L.), its planting soil medium and irrigation water sources used for crop production to determine the health risk. The results showed that the mean concentrations of different metals and metalloids in ground water samples i.e. Ni (0.14 mg L-1), Fe (1.29 mg L-1), Cu (0.10 mg L-1), Pb (0.55 mg L-1), As (0.10 mg L-1), Cr (2.38 mg L-1) and Cd (0.05 mg L-1) were over the permissible limits. Soil samples irrigated with ground water showed that concentrations of Cd (23.67 mg kg-1), Cr (26.66 mg kg-1) and As (45.97 mg kg-1) were above the permissible limits. Similarly, vegetable samples irrigated with ground water had a higher level of Cd (0.33 mg kg-1) than their prescribed safe limits. The bio-concentration factor ranged from 0.00 to 8.21 for all irrigation sources. The target hazard quotients (THQ) for Zn, Fe, and Cr were higher than the threshold value when ridge gourd was consumed, indicating a health concern. Similarly, hazard index values were 5.05, 28, 27, and 1.01, from groundwater, canal water, and sewage water, respectively. Target Cancer Risk (TCR) exposed Ni, Cr, Cd and As in canal water were sources of high cancer risk and Pb showed moderate cancer risk for the local community. These findings suggest that human intake of ridge gourd vegetable from the studied area may pose health hazards. Hence, frequent monitoring of different irrigation streams used in urban and semi-urban agriculture is strongly recommended to manage higher concentrations of phytotoxic metals and metalloids in crop produce and their associated health risks for humans.