Types Of Irrigation Water Research Articles

Fate and impact of wastewater-borne micropollutants in lettuce and the root-associated bacteria

The reuse of water for agricultural practices becomes progressively more important due to increasing demands for a transition to a circular economy. Treated wastewater can be an alternative option of blue water used for the irrigation of crops but its risks need to be evaluated. This study assesses the uptake and metabolization of pharmaceuticals and personal care products (PPCPs) derived from treated wastewater into lettuce as well as the impact on root-associated bacteria under a realistic and worst-case scenario. Lettuce was grown in a controlled greenhouse and irrigated with water or treated wastewater spiked with and without a mixture of fourteen different PPCPs at 10 μg/L or 100 μg/L. After harvesting the plants, the same soil was reused for a consecutive cultivation campaign to test for the accumulation of PPCPs. Twelve out of fourteen spiked PPCPs were detected in lettuce roots, and thirteen in leaves. In roots, highest concentrations were measured for sucralose, sulfamethoxazole and citalopram, while sucralose, acesulfame and carbamazepine were the highest in leaves. Higher PPCP concentrations were found in lettuce roots irrigated with spiked treated wastewater than in those irrigated with spiked water. The absolute bacterial abundance remained stable over both cultivation campaigns and was not affected by any of the treatments (type of irrigation water (water vs. wastewater) nor concentration of PPCPs). However, the irrigation of lettuce with treated wastewater had a significant effect on the microbial α-diversity indices at the end of the second cultivation campaign, and modified the structure and community composition of root-associated bacteria at the end of both campaigns. Five and fourteen bacterial families were shown to be responsible for the observed changes at the end of the first and second cultivation campaign, respectively. Relative abundance of Haliangium and the clade Allorhizobium-Neorhizobium-Pararhizobium-Rhizobium was significantly affected in response to PCPPs exposure. Caulobacter, Cellvibrio, Hydrogenophaga and Rhizobacter were significantly affected in microcosms irrigated with wastewater.

Impact of Recycled Water Irrigation on Soil Salinity and Its Remediation

Continuous use of recycled water (treated wastewater) over a long period of time may lead to the accumulation of salt in the root zone of the soil. This is due to the relatively higher levels of salt contained in the recycled water compared to a town water supply. The increase in salt concentration in the soil can adversely influence the amount of water a plant can uptake from the soil due to the osmotic effect. Despite significant benefits, recycled water may deteriorate soil health in terms of increased salinity and sodicity. Although several studies in the past have highlighted the increase of soil salinity due to recycled water irrigation, the phenomenon depends on the variability of soil characteristics. In this study, the impact of using three different types of irrigation water (with electrical conductivity 0.2, 0.8, and 2.0 dS/m) on the mechanism of salt accumulation in the soil was investigated. To contribute to the addition of the existing knowledge of soil salinisation, soil from two paddocks (i.e., D33 and Yarramundi) in Western Sydney, Australia were analysed, and relationships among parameters associated with salt accumulation were evaluated using the results from continuous column studies. Results show that if the irrigation is conducted with high saline water, there is a possibility for salinisation of soil to occur. To prevent this from occurring, one of the solutions could be to use a normal town water supply for irrigation at some intervals. This will allow for the leaching of excess salt accumulated in the soil to deeper layers.

Post-harvest growth and longevity of ornamental sunflowers irrigated using magnetised water with different irrigation depths

ABSTRACT With the water crisis affecting several countries, the use of innovative technologies and methods in irrigated agriculture is essential to increase water use efficiency. The use of magnetised water has been considered a possibility both for saving water resources and in increasing crop productivity and quality. Following this, the objective of the present study was to evaluate the growth and longevity of flower stems of ornamental sunflower (Helianthus annuus L.; Vincent’s Choice) irrigated with different irrigation depths and water subjected to magnetic field treatment. The treatments consisted of five percentage of crop evapotranspiration (ETc) (20, 70, 100, 130, and 160% of ETc) and two types of irrigation water (magnetised water; and ordinary water). The following characteristics were evaluated: plant height, stem diameter, inflorescence diameter, fresh and dry masses of the leaves and stems, fresh and dry masses of the inflorescence, and post-harvest longevity of the flower stems. The growth and post-harvest longevity characteristics were not influenced by the water type. An increase in irrigation depth promoted an increase in all analysed parameters. Regarding the commercialisation patterns of cut flowers, depth equal to or greater than 0.7 ETc yielded the best classification of ornamental sunflower.

Maximization of Water Productivity and Yield of Two Iceberg Lettuce Cultivars in Hydroponic Farming System Using Magnetically Treated Saline Water

Egypt has limited agricultural land, associated with the scarcity of irrigation water and rapid population growth. Hydroponic farming, seawater desalination and magnetic treatment are among the practical solutions for sustaining rapid population growth. In this regard, the main objective of the present research study was to design and construct a hierarchical engineering unit as a hydroponic farming system (soilless) to produce an iceberg lettuce crop using magnetically treated saline water. The treatments included four types of irrigation water: common irrigation water (IW1) with an electrical conductivity (EC) of 0.96 dS/m as a control treatment, magnetically treated common irrigation water (IW2) with an EC of 0.96 dS/m, saline water (IW3) with an EC of 4.56 dS/m and magnetically treated saline water (IW4) with an EC of 4.56 dS/m; three depletion ratios (DR) of field capacity (DR0 = 50%, DR1 = 60% and DR2 = 70%) and three slopes of hydroponic pipes (S1 = 0.0%, S2 = 0.025% and S3 = 0.075%). The results revealed that seawater contributed 7.15% to produce iceberg lettuce in the hydroponic system. The geometric parameter, the slope of the pipes, influenced the obtained luminous intensity by an average increase of 21% and 71% for S2 and S3, respectively, compared with the zero slope (horizontal pipes). Magnetization of irrigation water increased the total soluble solids (TSS) and enhanced the fresh weight and water productivity of both iceberg lettuce varieties used. The maximum percentages of TSS were 5.20% and 5.10% for lemur and iceberg 077, respectively, for the combination IW4DR2S2. The highest values of fresh weight and water productivity of 3.10 kg/m and 39.15 kg/m3 were recorded with the combinations IW3DR2S3 and IW4DR1S3, respectively, for lemur and iceberg lettuce. The percentages of these increases were 109.46% and 97.78%, respectively, when compared with the combination IW1DR0S1. The highest values of iceberg lettuce 077 fresh weight and water productivity were 2.93 kg/m and 36.15 kg/m3, respectively, which were recorded with the combination IW4DR1S3. The percentages of these increases were 112.32% and 120.56%, respectively, when compared with IW1DR0S1 (the control treatment).

Effects of excessive nitrogen fertilizer and soil moisture deficiency on antioxidant enzyme system and osmotic adjustment in tomato seedlings

Long-term excessive application of nitrogen fertilizer induces secondary salinization of soil, which results in inhibiting plant growth. In addition, soil moisture deficiency also affects plant growth. To investigate the effects of excessive nitrogen fertilizer and soil moisture deficiency on the antioxidant enzyme system, plant water relations were analyzed through pressure-volume (P-V) curve, and photosynthetic light response parameters in tomato (Solanum lycopersicum L. Myoko) seedlings, an indoor experiment about 50 d was conducted using two irrigation water amounts based on field capacity (soil moisture deficiency: 50%-80%; adequate water: 70%-80%), two nitrogen fertilizer rates (moderate nitrogen; excessive nitrogen fertilizer: 0.585 g/pot) and two types of irrigation water (tap water and microbial diluent). The results showed that excessive nitrogen fertilizer (N) and soil moisture deficiency (W) reduced the biomass of tomato seedlings. In comparison to CK (combination of adequate water and tap water quality), microbial dilution (EM) increased plant biomass by 5.2%. Also, the nitrogen application increased chlorophyll relative contents (SPAD). The maximum net photosynthetic rate (Pc) decreased with nitrogen application and increased with EM application and irrigation amount. Excessive nitrogen application increased the plant nitrate reductase activity (NR). The plant NR in the N treatment showed a 13.0% increase compared to CK, and the plant NR in the treatment of nitrogen application with water deficiency (WN) increased 34.0% compared to water deficiency (W). After applying excessive nitrogen, N, EM-N, WN, EM-WN respectively increased the plant nitrate reductase activity by 13.0%, 22.9%, 34.0% and 28.6%, compared with the corresponding treatment with moderate nitrogen (i.e., CK, EM, W and EM-W). In addition, the activities of antioxidant enzymes [superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT)] in four treatments of nitrogen application (N, EM-N, WN, EM-WN) also increased significantly. Both soil moisture and nitrogen fertilizer significantly affect the parameters of osmotic adjustment, which is manifested in the reduction of osmotic potential (πFT), and the increase in the osmotic concentration (Cosm) and concentration difference (ΔCosm). But the decrease in the relative water content of apoplast (ζap), indicating that water deficiency and excessive nitrogen reduced the water absorption and water retention capacity of tomatoes to a certain extent. In conclusion, excessive nitrogen application and soil moisture deficiency inhibit plant growth significantly in this experiment. Meanwhile, microbial dilution can alleviate excessive nitrogen fertilizer and water stress to some extent, but the effect was not significant. Keywords: antioxidant enzyme, nitrogen, osmotic adjustment, pressure-volume curve, stress, tomato, water DOI: 10.25165/j.ijabe.20221502.5555 Citation: Zhang Y J, Yu S E, Li Z J, Chang T T, Xu Q C, Xu H L, et al. Effects of excessive nitrogen fertilizer and soil moisture deficiency on antioxidant enzyme system and osmotic adjustment in tomato seedlings. Int J Agric & Biol Eng, 2022; 15(2): 127–134.

Implications of irrigation water quality in tropical farms

BACKGROUND AND OBJECTIVES: Irrigation system water quality is a complex issue that involves the combined effects of various surface water management parameters. Monitoring of irrigation water quality is essential for the sustainability of crop production and productivity. The department of Sucre, in northern Colombia, is predominantly a ranching and agricultural region where agriculture is the main source for livelihoods. The purpose of this study was to assess the physicochemical quality of surface water in irrigation systems at 141 farms.METHODS: To this end, 141 water samples were taken to determine 22 physicochemical parameters. All in-situ measurements and laboratory analysis were performed using standard methods. The results obtained were compared with the international standards proposed by the United Nations’ Food and Agriculture Organization and the World Health Organization. Salinity and sodicity were measured using the irrigation water classification diagram, and the level of correlation between the 22 variables was assessed by means of correlation analysis.FINDINGS: The results obtained indicate that based on the measured parameters, the water is classified as appropriate for use in irrigation systems. The maximum and minimum pH values were 9.32 and 4.40, respectively; the maximum and minimum values of electrical conductivity were 669 and 19.80 µS/cm respectively; the maximum and minimum values of total dissolved solids were 478 and 11.80 mg/L respectively, and the maximum and minimum values of the sodium adsorption ratio were 1.72 and 0.01 mEq/L, respectively. CONCLUSION: Cation and anion concentrations were within the limits allowed by the Food and Agriculture Organization and the WHO. According to the irrigation water classification diagram, the waters were classified as C1S1 and C2S1, which implies that there are no restrictions for their use in irrigation systems, water type (I) and type (II).

Impact of irrigation water type and sampling frequency on Microbial Water Quality Profiles required for compliance with U.S. Food Safety Modernization Act Produce Safety Rule standards

The U.S. Food Safety Modernization Act (FSMA) Produce Safety Rule (PSR) requires that farmers generate a Microbial Water Quality Profile (MWQP) from 20 samples per agricultural water source, taken over 2–4 years and five annual samples thereafter. Farmers must use the MWQP to ascertain a geometric mean (GM) of ≤126 CFU/100 mL and statistical threshold value (STV) of ≤410 CFU/100 mL of generic Escherichia coli. Farmers are responsible for collecting samples and paying for testing, incurring a financial and time burden. To determine if testing frequency can be reduced without compromising accuracy, water samples (n = 279) were collected from twelve sites in the U.S. Mid-Atlantic region from 2016 to 2018 comprising tidal brackish river, non-tidal fresh river, pond, vegetable processing, and reclaimed water. The GM and STV were calculated for all sites and water types using all samples, and for multiple sub-samples of <20 from each site and water type. A Monte Carlo simulation was used to determine the proportion of sub-sample sizes that yielded the same determination as the entire sample size of PSR standard compliance. Four sites, two pond and two reclaimed water sites, complied with PSR GM and STV requirements when using the entire sample set. When a water source's calculated GM and STV using the entire sample set hovered close to the PSR thresholds, sub-sample sizes approached the recommended 20 samples to reach a congruent compliance determination. However, 99% agreement was obtained with a sub-sample of five when the absolute difference between the GM and STV from total samples and the PSR thresholds was ≥2.6 and 4.5 log CFU/100 mL E. coli, respectively. These findings suggest that under certain conditions the MWQP may be generated with well below 20 samples, reducing the economic burden on farmers while still maintaining a representative MWQP.

Water Magnetization and Application of Soil Amendments Enhance Growth and Productivity of Snapdragon Plants

Freshwater resources are being rapidly depleted because of the increased demand resulting from exponential world population growth and the effects of climate change, especially in arid and semiarid regions (e.g., Saudi Arabia). The present study aimed to examine the changes in growth and inflorescence production of snapdragon (Antirrhinum majus L.) plants in response to irrigation with saline or magnetized water, in addition to application of inorganic and/or organic soil amendments. Three different water types—tap water, magnetized saline water, and nonmagnetized saline water—were used to irrigate A. majus plants with or without soil amendments consisting of ferrous sulfate (Fe2SO4) and/or peatmoss. Irrigation with magnetized saline water adversely affected vegetative growth, inflorescence production, mineral contents, and survival rates of A. majus plants as compared with irrigation with tap water or magnetized saline water. Nevertheless, compared with unmagnetized saline water treatment, magnetizing nonmagnetized saline water before irrigation significantly improved water characteristics and plant growth and survival. Moreover, the addition of inorganic or organic soil amendments enhanced the growth of A. majus plants regardless of irrigation water type. Interestingly, the combination of irrigating with magnetized saline water and soil amendments (Fe2SO4 and peatmoss) significantly enhanced the growth of A. majus plants to a level that was comparable to that of control plants irrigated with tap water without soil amendments. Magnetization improved water quality and increased plants’ ability to absorb water and nutrients from soil solution. The utilization of magnetized saline water for irrigating food and forage crops either alone or in combination with soil amendments has potential benefits that warrant further research.

Effects of Different Irrigation Waters and Silicon Doses on Leaf SPAD Meter Readings, Chlorophyll and Carotenoid Contents of Tomato Plants

This study was conducted to determine the effects of different irrigation water treatments and silicon doses on leaf SPAD meter readings, chlorophyll content and carotenoid contents of tomato plants. Tybiff Aq tomato seedling were grown in 3-liter pots filled with 1100 g of 1:1 peat-perlite mixture for 70 days. Four different type of irrigation waters were prepared with the use of sea and tap water. Irrigation waters included I) Full sea water, II) ½ sea water + ½ tap water, III) ¼ sea water + ¾ tap water, IV) Full tap water (control). Each irrigation water was supplemented with silica gel (SiO2.xH2O) at 0, 0.5, 1 and 2 mM Si doses. Nutrient solutions were supplied to meet macro and micronutrient requirements of tomato plants. Leaf chlorophyll-a, chlorophyll-b and total chlorophyll contents significantly increased with increasing tap water ratios of the irrigation water. Significant increases were observed in chlorophyll-a, chlorophyll-b and total chlorophyll contents with increasing silicon doses. Such increases achieved with silicon treatments were more remarkable for chlorophyll-a and total chlorophyll contents. Leaf chlorophyll-a, chlorophyll-b and total chlorophyll contents significantly decreased with increasing leaf sodium, chlorine and magnesium contents, but significantly increased with increasing leaf active iron and potassium contents. Leaf chlorophyll-a, chlorophyll-b and total chlorophyll contents increased with increasing leaf calcium contents, but such increases were not significant. Leaf carotenoid contents significantly increased with increasing tap water ratios of the irrigation water. Effects of silicon doses on leaf carotenoid contents varied with the type of irrigation water. The 0.5 mM silicon supplementation into tap water significantly increased carotenoid contents.

Zinc behavior in maize cropping system as influenced by coal application and magnetized Zn contaminated water

Irrigation of plants by contaminated water with metals is very common in countries facing freshwater scarcity. To enhance plant growth via improved absorption of essential metals including Zn from wastewater the magnetization of water as a modern approach, can be used. With the aim of investigating the effects of brown coal application and magnetizing contaminated water on the absorption of Zn and the yield of maize, a greenhouse experiment was conducted. The experiment was factorial arranged in a completely randomized design with four levels of brown coal (0, 1, 2, and 4% w/w), and 5 types of irrigation water (distilled water, water contaminated with Cu-sulfate, water contaminated with Cu-nitrate, magnetized water contaminated with Cu-sulfate, and magnetized water contaminated with Cu-nitrate). Maize was irrigated according to the treatments of irrigation types, so that the total concentration of Zn added to the pots receiving Zn-contaminated water reached 1200 mg kg−1 at the end of experiment. Results showed that plants irrigated with Zn contaminated water significantly increased shoot dry matter yield, as compared to that of control treatment, due to high buffering capacity of the studied calcareous soil for stabilization of Zn. Magnetized water significantly increased mean shoot and root Zn uptake, uptake efficiency, phytoextraction efficiency, translocation factor, and translocation efficiency. Due to the improvement of Zn uptake by maize following the use of magnetized water, it is tentatively concluded that magnetization of waters with high level of Zn may be used for correcting Zn deficiency in calcareous soils.

Spray irrigation with microcystins-rich water affects plant performance from the microscopic to the functional level and food safety of spinach (Spinacia oleracea L.)

Irrigation water coming from freshwater bodies that suffer toxic cyanobacterial blooms causes adverse effects on crop productivity and quality and raises concerns regarding food contamination and human exposure to toxins. The common agricultural practice of spray irrigation is an important exposure route to cyanotoxins, yet its impact on crops has received little attention. In the present study we attempted an integrated approach at the macro- and microscopic level to investigate whether spray or drip irrigation with microcystins (MCs)-rich water differently affect spinach performance. Growth and functional features, structural characteristics of stomata, and toxin bioaccumulation were determined. Additionally, the impact of irrigation method and water type on the abundance of leaf-attached microorganisms was assessed. Drip irrigation with MCs-rich water had detrimental effects on growth and photosynthetic characteristics of spinach, while spray irrigation ameliorated to various extents the observed impairments. The stomatal characteristics were differently affected by the irrigation method. Drip-irrigated spinach leaves showed significantly lower stomatal density in the abaxial epidermis and smaller stomatal size in the adaxial side compared to spray-irrigation treatment. Nevertheless, the latter deteriorated traits related to fresh produce quality and safety for human consumption; both the abundance of leaf-attached microorganisms and the MCs bioaccumulation in edible tissues well exceeded the corresponding values of drip-irrigated spinach with MC-rich water. The results highlight the significance of both the use of MCs-contaminated water in vegetable production and the irrigation method in shaping plant responses as well as health risk due to human and livestock exposure to MCs.

Effect of Irrigation Water Source on Secondary Metabolites in Salix acmophylla and Their Potential to Impair Exsheathment of Gastro-Intestinal Nematodes

Willows (Salix), which are found worldwide, have secondary metabolites that are valuable as dietary supplements for animal feed. The objectives of the current study were to test the effects of irrigation source on the production of secondary metabolites and their potential to inhibit nematode exsheathment. Three willow ecotypes (Kishon, Meah Shearim, and Golan) were irrigated with Fresh Tap Water (FW) or Treated Wastewater (TWW). TWW irrigation resulted in a doubling of biomass production compared with FW, probably due to the presence of more nutrients, particularly nitrogen. The type of irrigation water (TWW vs. FW) did not affect the quantity and quality of secondary metabolites, such as phenols, in all three willow ecotypes, although there was a difference in the chemical profile of glycoside phenols between willow ecotypes. Biomass and secondary metabolite production differed greatly between ecotypes, which was evident in the differing concentrations of phenols and flavonoids. These varying concentrations in turned affected the inhibition of the exsheathment of larval L3 nematodes. The ethanol extract of the Kishon ecotype consistently resulted in more than 90% exsheathment inhibition when tested on the L3 larval stage, whereas extracts from Meah Shearim and Golan resulted in lesser inhibition. A sub-fraction of the ethyl acetate fraction obtained from Kishon had maximum activity with more than 90% exsheathment inhibition.

Initial growth of zucchini irrigated with saline water in soil with biofertilizers

Zucchini culture is slightly sensitive to salinity and is among the ten vegetables of highest economic value, with characteristics of precocity and easy cultivation. These characteristics are some of the reasons for the expansion of its cultivation among small producers. Thus, the objective was to evaluate the effect of different levels of salinity in the irrigation water and biofertilizer types on the initial growth of the zucchini (Cucurbita pepo L.) culture. The experiment was carried out in the full sunlight in a randomized block design, in a 5x2 factorial arrangement. The treatments consisted of a combination of five types of biofertilizers (quail, sheep, mixed, bovine, and crab) and two salinity levels of the irrigation water (0.8 and 2.5 dS m-1), with five replicates. At 30 days after transplanting, the following variables were evaluated: electrical conductivity of the substrate, plant height, number of leaves, roots length, stem diameter, leaf area, chlorophyll content, dry mass of the aerial part, root dry mass, and total dry mass. Salt stress negatively interferes with the accumulation of zucchini plant biomass. Quail, bovine, and sheep biofertilizers are more efficient about plant height, number of leaves, and stem diameter. The sheep biofertilizer attenuates the salt stress for the dry mass of the aerial part, the root, and the total dry mass.

Effects of Various Quantities of Three Irrigation Water Types on Yield and Fruit Quality of ‘Succary’ Date Palm

A field experiment was conducted on date palm trees (Phoenix dactylifera ‘Succary’) cultivated on sandy loam soil from 2017 to 2018. This study investigated the effects of providing water of three different qualities, namely freshwater (FR) and two saline water sources: reclaimed wastewater (RW) and well-water (WE) applied through three irrigation levels representing 50% (I50), 100% (I100), and 150% (I150) of crop evapotranspiration (ETc), on the soil water and salt distribution patterns, yield, water productivity (WP), and fruit quality of the ′Succary′ date palm. The electrical conductivity (ECw) of FR, RW, and WE were 0.18, 2.06, and 3.94 dS m−1, respectively. Results showed that WE applied by the I150 treatment had the highest soil water content, followed by RW used in the I100 irrigation level and FR with I50, whereas the soil salt content was high for WE applied in the I50 level and low for FR applied by the I150 treatment. Deficit irrigation (I50) of date palms with either RW or WE reduced date yields on average 86 kg per tree, whereas the yield increased under over-irrigation (I150) with FR to 123.25 kg per tree. High WP values were observed in the I50 treatments with FR, RW, or WE (on average 1.82, 1.68, and 1.67 kg m−3, respectively), whereas the I150 treatment with each of the three water types showed the lowest WP values. Fruit weight and size were the lowest in the full irrigation (I100) with WE, whereas the I150 treatment with RW showed the highest values. There were no significant differences in either total soluble solids (TSS) or acidity values when the irrigation level decreased from 100% to 50% ETc. Compared with both I50 and I100 treatments, reduced values of both TSS and acidity were observed in the I150 treatment when ECw decreased from 3.94 to 0.18 dS m−1,. Fruit moisture content decreased with the application of saline irrigation water (i.e., RW or WE). Total sugar and non-reducing sugar contents in fruits were found to be decreased in the combination of RW and I150, whereas the 50% ETc irrigation level caused an increment in both parameters. These results suggest that the application of deficit irrigation to date palm trees grown in arid regions, either with FR or without it, can sufficiently maximize WP and improve the quality of fruits but negatively affects yield, especially when saline water is applied. The use of saline water for irrigation may negatively affect plants because of salt accumulation in the soil in the long run.

Impact of levels of nitrogen fertilizer and types of irrigation water on yield and yield components of barley crop

A pot experiment was carried out at the Experimental Farm, Faculty of Agriculture, South Valley University, Qena, Egypt during the 2015-2016 and 2016-2017 seasons to study the effect of nitrogen fertilizer levels and types of irrigation water (W1; Tap water only, W2; manipulated wastewater with sandy filter, W3; manipulated wastewater with nano-titanium dioxide + sandy filter and W4; a mixture of treated wastewater with nano-titanium dioxide and sandy filter + tap water) on growth, yield and its attributes of barley cv. Giza 2000. A randomized complete block design (RCBD) using a split-plot arrangement with four replications was used. The main plot was four different levels of nitrogen fertilizer and the sub-plot were four different types of irrigation water. The seeds of above mentioned variety were used in the pot experiments. The highest mean values of plant height, number of tillers plant-1, spike length, number of grains spike-1, spike weight, biological yield plant-1 and grain yield plant-1 were obtained from high level of nitrogen (60 kg N fed-1). Also, the highest values of above traits were obtained from irrigation with treated wastewater with nano-titanium dioxide and sandy filter + tap water (W4). It could be concluded that under the conditions of the experiment, application of high levels of nitrogen (N60) under irrigation with treated wastewater with nano-titanium dioxide and sandy filter+ tap water (W4) is recommended.

Influence of the soil water retention curve type and magnetic water treatment on lettuce irrigation management responses

Abstract This study aimed to evaluate the influence of magnetized water use on lettuce irrigation management responses, and based on the generated data, to evaluate by simulation the influence of soil water retention curve type on the lettuce irrigation management responses. This work was divided into three stages: 1 – determination of field and laboratory soil water retention curves; 2 – lettuce crop irrigation management experiment using soil water retention curve with field data, evaluating different soil water tensions to start irrigation and different water types (magnetically treated water, and non-treated water); and 3 – estimation of the irrigation management responses (simulation) using the soil water retention curve performed in the laboratory (using non-treated water), compared with the experimental results (stage 2). The use of magnetically treated water determined the soil moisture maintenance for a longer time and fewer irrigation events, leading to less water being applied and electricity consumption. The use of the soil water retention curve derived from the field data determined less water and electric energy consumption in Lucy Brown lettuce irrigation, in comparison with the simulated use of the soil water retention curve from laboratory data.

Geochemical variability in the soils of Bangladesh as affected by sources of irrigation water and inundation land types

Paddy soils in Bangladesh experience extensive irrigation with groundwater and surface water, both having variable geochemical constituents. The soils also have topological variations across the landscape. To understand the geochemical variability in the soils as affected by the different sources of irrigation water and the topographical variability, cultivation zones of paddy soils irrigated with both groundwater (n = 904) and surface water (n = 281) across Bangladesh were sampled and analyzed for a suit of seventeen geochemical elements. This study also assessed the extent and distribution of arsenic and the other geochemical elements in the paddy soils (n = 1209) as well as in a set of neighboring non-paddy soils (n = 235) within the different inundation land types (highland, medium highland-1, medium highland-2, medium lowland, lowland and very lowland) of Bangladesh. The mean concentrations of aluminum (26,000 mg/kg), cobalt (13 mg/kg), copper (32 mg/kg), iron (28,250 mg/kg), lead (18 mg/kg), magnesium (8050 mg/kg), molybdenum (1.02 mg/kg), nickel (41 mg/kg), potassium (4870 mg/kg), sodium (750 mg/kg) and zinc (70 mg/kg) in the surface water-irrigated paddy soils were found to be significantly (0.001 ≥ p ≤ 0.05) higher compared to the concentrations in the soils irrigated with groundwater (23,400; 12; 28; 25,650; 17; 7000; 0.96; 36; 4350; 600; and 62 mg/kg, respectively). Therefore, surface water used for paddy irrigation could increase the inputs of a number of toxic elements in the paddy soils having potential risk of crop contamination. Arsenic in the paddy and non-paddy soils varied significantly (F = 24.74, p < 0.001 and F = 3.42, p < 0.01, respectively) within the inundation land types, the very lowland (9.95 and 6.72 mg/kg, respectively) and lowland (8.33 and 5.20 mg/kg, respectively) having the highest mean arsenic concentrations and the medium highland-1 (5.27 and 5.17 mg/kg, respectively) having the lowest. The concentrations of the other geochemical elements analyzed were also observed to be higher, in general, in the soils of very lowland and lowland. Since the low-level lands are predominantly used for paddy cultivation, higher concentrations of various toxic elements, particularly arsenic, in such soils pose an increased risk of rice toxicity in Bangladesh. The results of this study present an inimitable geochemical database for the surface soils across Bangladesh which can be used in any future studies on the geomorphologically variable agricultural and non-agricultural Bangladeshi soils, providing a basis for environmental pollution assessment and sustainable mitigation approaches.

Crescimento e qualidade de mudas de baru em reposta a hidroretentor e água magnetizada

O baru (Dipteryx alata Vogel) é uma espécie nativa do Cerrado de usos múltiplos. O objetivo desse trabalho foi verificar a influência da associação entre doses de hidroretentor e tipos de água de irrigação no crescimento e na qualidade de mudas de baru. O delineamento experimental utilizado foi o de blocos ao acaso 5x2x5, com 5 repetições, sendo 5 doses de hidroretentor (0, 2, 4, 6, 8 g L-1 - DH), 2 águas de irrigação (normal - AN e magnetizada - AM) e 5 épocas de avaliação (15, 30, 45, 60, 75 e 90 dias após a emergência – DAE). A unidade experimental era composta de 4 mudas, cultivadas em substrato comercial sob tubetes de 120 cm³ de capacidade. O crescimento foi avaliado por características morfológicas (altura de planta- AP, diâmetro de caule - DC e número de folhas – NF, em intervalos quinzenais) e por produção de matéria seca (matérias secas de raiz, caule e folhas aos 90 DAE). As matérias secas foram usadas para estimar as razões de matéria seca. A qualidade foi determinada pelo Índice de Qualidade de Dickson (IQD). Observou-se que o crescimento em AF e NF foram limitados, enquanto que DC aumentou linearmente com o tempo. A associação entre DH e AM reduzem a AP, mas compensam no NF. A não diferença observada nas matérias secas, razões de matérias secas e IQD foram atribuídas à plasticidade fenotípica do baru. DH acima de 0,78 g L-1 não influenciam expressivamente no sistema radicular devido a limitação do tubete de 120 cm³.

Environmental and genetic interaction of some Oat genotypes under the influence of different types of irrigation water

In this study, ten oat genotypes (Alguda , Anatolia , Pimula ,Genzania ,Hamel, Icarda short ,Kangaroo ,Icarda tall ,Mitika and Possum) were used under the impact of three irrigation water types and two agricultural seasons. Performance and genetic and environmental interaction were studied according to Eberhart and Russel and cluster analysis for Days to anthesis , plant height ,flag leaf area,no.effective tillers , no.grains.panicul , 1000 grains weight and grain yield (t.he-1), We reached the most important results that was through obtaining statistically significant in analysis of variance table of the sources of difference in environments, genotypes and the interaction between them for all characteristics under study. Genotype (6) distinguished in no.effective tillers (141.06 tiller.m-2 ), no.grains.panicul-1 (66.89 grain.panicul-1) and grain yield (1.48 t.he-1) and genotype (1) in days to anthesis (110.70 day) and no.effective tillers (136.67 tiller.m-2) and the interaction between fourth environment and genotype (6) for no.grains.panicul (66.67 grains,panicul-1) .In addition to this uniqueness in performance, genotype (6) proved its stability for plant height, 1000 grains weight and grain yield (t.he-1) .These indices are feasible with evidence that they coincided with yield and some of its components, as well as to high stability to be implemented in future after testing with other factors. In addition to that, obtaining the state of the genetic distance between genotypes tested across environments, in particular genotype (8) with genotypes (6 and 7) and hence can be used in breeding programs, especially hybridization.

Soil texture and properties rather than irrigation water type shape the diversity and composition of soil microbial communities

Around the world, water scarcity is advocating for treated wastewater (TWW) reuse, especially for agricultural irrigation. However, TWW contains inorganic substances, dissolved organic matter and microorganisms that may alter soil health and fertility. In this study, it was hypothesized that irrigation would differently alter the soil microbial communities in accordance with soil types and properties, but independent of water quality. It was further predicted that the differences in soil community would be mediated by clay content due to its physical properties and effect on organic matter content. To test these predictions, TWW and potable water (PW) were used to irrigate different soil types (clay, loam and loamy sand) for growing two Cucumis species during two cultivation seasons. The abundance, diversity and function of the soil microbial communities (bacteria and protists) were monitored in 248 samples of water and soil. The results demonstrate that the microbial communities significantly differed between water qualities, yet these differences did not carry to the irrigated soils. However, soil types significantly altered the microbial communities, particularly clay content, that correlated with a decrease in diversity indices, and changes in the composition of members of the Proteobacteria, Actinobacteria and SAR taxa. Accordingly, myriad organic compounds degradation pathways were identified in the clay soil samples. The results suggest that soils with lower clay content may be spatially segregated at the micro-scale, resulting in niche partitioning and higher bacterial diversity regardless of irrigation water type. Therefore, soil texture and properties shape agricultural soils' microbial communities.