Irrigation Water Levels Research Articles

Effects of Saline Water and Irrigation Interval on Soybean (Glycine max) Yield

The declining availability of fresh water has become a worldwide problem, which maintains the development of alternative, secondary quality water resources for agricultural use. Several studies recommend that give attention for selected crops that can tolerate a degree of water and salinity stresses when saline water is used for irrigation. In this study, the effects of different irrigation intervals at different salinity levels of irrigation water on Soybean yield and their impacts investigated using three irrigation intervals (I1 =3 days, I2=4 days and I3=5 days) with four salinity levels (S1=4 dSm-1, 5 dSm-1 and 6 dSm-1) in a factorial combination using CRD with three replications. The result showed that salinity, irrigation interval and their interaction were highly significance effects (p<0.001) on number of pod per plant, number of seed per plant and grain yield of Soybean. The highest number of pod number (88.33), grain yield (2.31 ton/ha) and number of seed per plant (172.33) was recorded from Soybean which was irrigated with the first salinity level, i.e., fresh water (S1) with irrigation interval one (3 days), S1I1; while the lowest pod number per plant (6.67), number of seed per plant (12.67) and minimum grin yield (0.034 ton/ha) was obtained from Soybean irrigated by salinity level four (S4) with 5 days irrigation interval (S4I3).

Irrigation control system design for paddy field by means of internet of things

During this time the control of the water level that is done is still using manual tools in the form of floodgates placed between rice fields and irrigation. Given the importance of controlling and monitoring the level of irrigation water in rice fields, the authors get the idea to create a control system to close the irrigation floodgates on rice fields for farmers. In addition to notification in the form of a SMS (Short Message Service) reply to the telegram application, the open and close irrigation door system in paddy fields is a major alternative that is very useful for farmers to prevent crop failures if the water in the paddy fields exceeds the limit. In this system utilizing the work of ultrasonic sensors to measure any changes in water level in the paddy fields, then the data will be received and processed in the nodemcu and water level notifications will be sent to the telegram, to drive the irrigation door on the paddy using a servo motor that will open and close the irrigation door on rice fields automatically according to the conditions specified. if the water level is <2 cm, the irrigation door will open, the buzzer will not sound. And if the water level below> 2 cm, the irrigation door will be closed, the buzzer will sound as a sign that the water needs in the field are sufficient. While the notification in the form of an sms will be sent to the telegram.

Optimizing Essential Oil Yield and Water Use Efficiency of Lemongrass (Cymbopogon citratus L.) Under Different Furrow Application Method and Deficit of Irrigation Water Levels in Lemongrass Production

Appropriate agricultural water management and implementation of deficit irrigation methods can reduce water usage in addition to minimizing the adverse effects of irrigation agriculture. The experiment was conducted Wondo Genet, Ethiopia for three consecutive years to optimize the essential oil yield and water use efficiency of Lemongrass. Three levels of deficit irrigation and furrow application method were used. The study revealed that the maximum Lemongrass essential oil yield of 55.12 kg ha-1 was obtained from no deficit irrigation with conventional furrow application method while the minimum oil yield 36.03 kg ha-1 obtained from 50% ETc (Evapotranspiration of crop) under fixed furrow application method. The optimum lemongrass essential oil yield 100% ETc under alternate furrow application method which is statistically similar to the maximum oil yield. Statistically, the highest water use efficiency was obtained from 50% ETc under alternate furrow application method. Therefore, the optimum Lemongrass essential yield can be produced under alternate furrow application method with 1005 ETc which provides the water use efficiency of 0.041 kg m-3.

Assessing the effectiveness of drip irrigation combined with agricultural mulches on the performance of tomato (Lycopersicon esculentum) under water constraint conditions of Lam Dong Province, Vietnam

The present investigation was undertaken during the spring crop (January to June 2019) at greenhouse in the Don Duong cultivation farm, Lam Dong province, Vietnam to evaluate the effect of drip irrigation combined with agricultural mulches on RITA tomato. The study is conducted applying agricultural mulches in greenhouse (AMG) with irrigation water level (IWL) 80% of actual evapotranspiration (ETa) and no agricultural mulches outside greenhouse (AMO) with IWL 100% of ETa to plant tomatoes cuttings. Based on the findings, highest tomato yield obtained for AMG was 81.6 ton/ha while for AMO was 67.8 ton/ha. The highest income for AMO case was US$ 4559/ha while for AMG case achieved up to US$ 7658/ha. The study, therefore, demonstrated the effect of the drip irrigation combined with agricultural mulches compared to the agricultural un-mulches case.

Tolerance to irrigation water salinity in physalis plants: productive aspects

The cultivation of non-traditional fruits has gained ground in the horticulture sector, but which, in certain situations, are plants that require previous studies related to soil adaptability, climate, and irrigation water quality. In this sense, this work aimed to evaluate the effects of irrigation water salinity on Physalis peruviana L. (fisális) plants in the different growth phases. The experimental area was installed on the premises of the Federal University of Campina Grande, adopting a casualized block design, with four saline levels of irrigation water (0.3; 1.2; 2.1 and 3.0 dS m-1) and five repetitions per treatment. The variables analyzed were: stem diameter, plant height and number of leaves every 15 days, leaf area at 55 days after transplanting, number of side branches, number of flower buds, number of flowers, average fruit weight, polar diameter, and equatorial diameter of fruits, number of fruits per plant and productivity. According to the results, the plants were tolerant to saline levels of irrigation water of up to 3.0 dS m-1, without prejudice to the phenological and productive characteristics of the crop. The unitary increase in the salinity of the irrigation water did not result in damage to the physiological characteristics of the plants until the 60 days of transplanting.

Melon cultivation irrigated with saline waters promote chemical alterations in an acrisol

The objective of the present study was to evaluate the salinization process and the changes in the chemical properties of an Acrisol cultivated with melon irrigated with water of different saline concentrations. The experiment was carried out in the field conditions using the experimental design of randomized blocks, arranged in split-plot. The plots were composed of salinity levels of irrigation water, expressed in terms of water electrical conductivity (ECw): 0.54; 1.48; 2.02 dS m-1; and the sub-plots for melon cultivars: Sancho and Medellín (Toad Skin), Mandacaru (Yellow), Nectar (Galia) and Sedna (Cantaloupe). Soil samples were collected at the beginning and end of the crop cycle to evaluate the changes in the physical-chemical properties of the soil. The electrical conductivity of saturation extract in the soil profile varied for each cultivar, observing high salinity values in soils with cultivars with lower water demand (Sedna and Nectar). The salinity of the soil was lower than the electrical conductivity of the irrigation water in the treatments with high values of ECw. The soil pH values showed little reaction in relation to the initial values. The exchangeable sodium percentage values were approximate twice the sodium adsorption ratio of the saturation stratum.

Evaluation of the bioaccumulation of mercury (Hg) and fluorine (F) in garden produce in south Benin

Objectives: The richness of the soils in metallic trace elements (MTEs) and Fluorine, which are potentially toxic elements, makes it necessary to pay attention to the risks of transfer of these elements to the food chain. The aim of this study is to evaluate the content of mercury and fluorine in soils, irrigation water and market garden products in South Benin. Methodology and Results: A total of 21 composite soil samples (0-20cm), 21 samples of irrigation water per growing area and 87 plant samples were collected. After sampling under aseptic conditions, they were sent for analysis in laboratories. The Excel spreadsheet calculated the contents and the GraphPad Prism 8.0 calculated the averages and tests of two ways. Before determining the bioaccumulation, the contents were compared to the minimum concentration referenced by international standards. All matrices were contaminated with mercury and fluorine. The minimum reference concentration (0.55mg/Kg) was higher than the average levels of the study soils in Mercury (0.11±0.1. 10-2 to 0.164±0.345 .10-3 mg/Kg) and in Fluorine (8.123±1.772 to 23.5±1.126mg/Kg). Mercury and Fluorine levels in site irrigation water were below the standards. The levels of mercury (0.46 .10-3 ±0.13 .10-4 to 0.001±0.38. 10-4 mg/L) and fluorine (0.15±0.07 to 2.17±0.41mg/L) in the irrigation water of the sites are lower than the standards, except for the Houéyiho borehole. In leaves such as amaranth, there was a very significant difference (0.001 &lt; p &lt; 0.01) at Sèmekpodji and Grand-popo. Amaranth is a leaf that is in direct contact with the chemicals used in the environment and could absorb mercury. Fluorine levels exceed the maximum recommended concentration (0.05 mg/Kg) so the vegetables are polluted with fluorine. Conclusion and application of results: In Houéyiho, a medium bioaccumulation in amaranths and carrots was observed while in chili peppers bioaccumulation was low. On the other hand, in Sèmè-kpodji and Grandpopo, a low bioaccumulation of mercury in all the vegetables was observed. Fluorine bioaccumulation is medium in amaranth and carrot at Houéyiho and Sèmè-kpodji and low in chilli peppers at both sites. While bioaccumulation is low in vegetables produced at the Grand-popo site. Key words: bioaccumulation, soil contamination, vegetable contamination, mercury, fluorine, MRC, Benin

Water Saving and Yield of Potatoes under Partial Root-Zone Drying Drip Irrigation Technique: Field and Modelling Study Using SALTMED Model in Saudi Arabia

This study aims to evaluate the Partial Root Zone Drying Irrigation System (PRD) as one of the modern technologies that provide irrigation water and increase the efficiency of its use on potato crop. The effect of applying the PRD conventional deficit irrigation (CDI) on the efficiency and water saving in potato crops using the drip surface (S) and subsurface (SS) irrigation methods were investigated. SALTMED model used to predict soil moisture and salinity distribution, soil nitrogen dynamics, and yield of potato crop using the different irrigation levels (150%, 100%, and 50% of Crop evapotranspiration (ETc)). The study showed that the water use efficiency (WUE) decreases with increasing levels of irrigation water, as it ranged between 2.96 and 8.38 kgm−3, 2.77 and 7.01 kgm−3 for surface irrigation PRD and CDI, respectively, when the amounts of irrigation water varied from 308 mm to 1174 mm, respectively. The study showed that the irrigation efficiencies were the highest when using PRD system in all treatments when irrigating the potato crop during the spring season, and it was more efficient in the case of using subsurface irrigation method. The results show that the soil moisture (SM) was high in 25–45 cm at 150% of ETc was 0.166 and 0.263 m3m−3 for the first and last stages of growth, respectively. 100% of ETc, (SM) was 0.296 m3m−3 at 0–25 cm, 0.195 m3m−3 at 25–45 cm, 0.179 m3m−3 at 45–62 cm, depths, respectively. whereas 50% of ETc, (SM) was 0.162 m3m−3 at 0–25 cm, 0.195 m3m−3 at 25–85 cm, depths. At 100% of ETc, soil salinity was 5.15, 4.37, 3.3, and 4.5 dSm−1, whereas at 50%, ETc, these values were 5.64, 9.6, 3.3, and 4.2 dSm−1. Statistical indicators showed that the model underestimated yield, for 150%, 100%, and 50% of ETc. Therefore, it can be concluded that yield and WUE using PRD systems were the highest in the potato crop compare to CDI surface and sub-surface, and SALTMED model can predict the moisture distribution, salinity, and yield of potatoes after accurate adjustment.

Soil properties as influenced by use of water having variable salinity and sodicity

A pot experiment was conducted during summer season of 2018 at Net House, Department of Agricultural Chemistry and Soil Science, College of Agriculture, Junagadh Agricultural University, Junagadh to study the influence of different levels of saline and sodic irrigation water on soil properties. The treatment consists of four levels each of salinity (2, 4, 6 and 8 dS m-1) and sodicity (5.0, 10.0, 15.0 and 20.0 SAR) of irrigation water by adopting factorial CRD with three replications. The available macronutrients (N, P2O5 and K2O) and organic carbon of soil after harvest of the crop were found maximum with EC-2 dS m-1 and SAR-5.0 level of irrigation water. The water soluble and exchangeable Ca, Mg and Na and soil properties like EC2.5, ECe, pH2.5, pHs, CEC and ESP was found maximum with EC-8 dS m-1 while water soluble and exchangeable K was found maximum with EC-2 dS m-1. The water soluble and exchangeable Na was found maximum with SAR-20.0, whereas water soluble and exchangeable Ca, Mg and K were found minimum with SAR- 20.0. The soil properties like ECe, pH2.5, pHs and ESP of the soil was found maximum with SAR- 20.0, but CEC was found maximum with SAR-5.0. The combined effect of saline and sodic irrigation water was found significant on available N and water soluble cations Ca++, Mg++, Na+, K+, exchangeable Na+, ESP, ECe and pH2.5 of soil after harvest of groundnut.

Influence of water having variable salinity and sodicity on groundnut- I : Effect on growth, yield attributes, yield and quality

A pot experiment was conducted at Net House, Department of Agricultural Chemistry and Soil Science, Junagadh Agricultural University, Junagadh to assess four levels each of salinity (2, 4, 6 and 8 dS m-1) and sodicity (5.0, 10.0, 15.0 and 20.0 SAR) of irrigation water on groundnut by adopting factorial CRD with three replications. The results indicated that application of different levels of saline and sodic irrigation water produced significant effect on growth, yield attributes, yield and quality of groundnut crop. The maximum plant height, number of mature and immature pods plant-1, weight of mature and immature pods plant-1, days to 50 % flowering, pod and haulm yield and harvest index were observed with EC 2 dS m-1 and SAR 5.0 and the lowest with EC 8 dS m-1 and SAR 20.0 of irrigation water. The quality parameters like seed index and protein content were found maximum with the saline irrigation water level of EC-2 dS m-1 and SAR-5.0, but there was no any pod formation recorded with EC-8 dS m-1. The interaction effect between salinity and sodicity levels of irrigation water on pod (8.10 g pot-1), kernel (5.36 g pot-1) and biological (26.61 g pot-1) yield were found significantly the highest with C1×S1 (EC- 2.0 dS m-1×SAR- 5.0) while no any pod formation were observed with C4×S1, C4×S2, C4×S3 and C4×S4 level of irrigation water.

Influence of water having variable salinity and sodicity on groundnut-II : Effect on nutrient content and uptake

A pot experiment was conducted at Net House, Department of Agricultural Chemistry and Soil Science, College of Agriculture, Junagadh Agricultural University, Junagadh to assess the different levels of saline and sodic irrigation water on content and uptake of nutrient by groundnut during the Summer-2018. The treatment consists of four levels each of salinity (2, 4, 6 and 8 dS m-1) and sodicity (5.0, 10.0, 15.0 and 20.0 SAR) of irrigation water by adopting factorial CRD with three replications. The results indicated that application of different levels of saline and sodic irrigation water produced significant effect on content and uptake of N, P and K by kernel and haulm of groundnut. The highest N, P and K content (3.76 %, 0.34 % and 0.67 %) and uptake (163.6, 13.34 and 25.14 mg pot-1) by kernel and content (1.08 %, 0.15 % and 0.40 %) and uptake (177.8, 25.01 and 66.5 mg pot-1) by haulm, respectively were observed with EC-2 dS m-1 level of salinity of irrigation water, but the lowest content and uptake by kernel were observed with EC-6 dS m-1 and by haulm at EC-8 dS m-1 levels of salinity of irrigation water. There was no any pod formation were observed with EC-8 dS m-1, hence, content and uptake of nutrients by kernel considered zero. While the highest N, P and K content (2.85 %, 0.22 % and 0.42 %) and uptake (109, 5.93 and 11.45 mg pot-1) by kernel and content (1.01 %, 0.13 % and 0.37 %) and uptake (135.5, 17.80 and 48.6 mg pot-1) by haulm, respectively were observed with SAR- 5.0 level of sodicity of irrigation water. The interaction effect between salinity and sodicity levels of irrigation water on concentration and uptake of N by kernel and haulm were found significantly the highest with C1×S1 (EC- 2.0 dS m-1 × SAR- 5.0) level of salinity and sodicity of irrigation water.

Effect of Irrigation Waters in Different Salinity Levels on Crop Yield and Energy Use in Greenhouse Tomato Production in Turkey: A Case Study in Kırklareli Province

This study was carried out in a quonset type plastic covered unheated greenhouse on the lands of Atatürk Soil Water and Agricultural Meteorology Institute in Kırklareli, Turkey. In the study, the effect of different salinity and irrigation water levels which were applied to tomato plant, irrigated by drip irrigation in greenhouse, on yield and energy use efficiency was evaluated and the optimum irrigation application was determined. In the study, ‘Swanson F1’ type tomato was grown as plant material. The trial was carried out on 36 parcels with three repetitions according to split plots trial design and four different irrigation water salinity levels were on main plots and three irrigation levels were on sub plots. The best result was obtained from T1S2 subject in terms of yield and energy use efficiency. The average yield was determined as 109060 kg ha-1 and energy output/input ratio, energy productivity and specific energy were found as 1.51, 1.89 kg MJ-1 and 0.53 MJ kg-1 in T1S2 subject, respectively. It was concluded that the optimum method should be on low salinity level and the irrigation water application should be on the level in order to bring the current moisture level to the field capacity.

EFFECT OF SALINE IRRIGATION WATER LEVELS ON THE GROWTH OF TWO ZINNIA ELEGANS L. CULTIVARS

The production and growth of ornamental plants are markedly affected by water deficiency. Therefore, enhancing their yield during the drought period has become the main goal in plant breeding. Two Zinnia elegans L. cultivars (Short Stuff and Profusion) were employed in this investigation to determine the effect of salinity and drought tolerance on plant growth for translation to a salinity and drought tolerance breeding program. Four irrigation treatments based on F.C. of medina used, (T1= 40, T2= 60, T3= 80, and T4= 100% (control) of field capacity) under five salinity levels (electrical conductivity (EC) of 0.63 dS m-1 (control)), EC1= 1.6, EC2= 3.1, EC3= 6.3, and EC4= 9.4 dS m-1) were imposed throughout a 120-day growing period using a drip irrigation system. The vegetative growth yield and the flowering characteristics were determined and gas exchange measurements were recorded. All flowering and vegetative characteristics decreased as the level of deficit irrigation water increased. Both cultivars treated with 40% under EC3= 6.3 and EC4= 9.4 dS m-1 did not flower. Nonetheless, significant differences were found between the two cultivars for all characteristics, indicating that they could be considered when adjusting for salinity and drought tolerance. Profusion cv. displayed better performance than Short Stuff cv., when grown under 80% and 100% irrigation treatments and the salinity levels, except for 40% with EC3 and EC4 which did not result in flower yield. Leaf chlorophylls content (chl. a, b, and total) reduced with the increase in the salinity level and with increasing deficit irrigation water treatments. Content of leaf minerals, such as Ca2+, Na+, and Cl-, was also determined. For both cultivars, Ca2+ content decreased as irrigation salinity increased, while Cl- and Na+ contents increased as salinity increased in the plant tissue following irrigation.

Potential of Biochar Application to Mitigate Salinity Stress in Eggplant

Salinity stress is among the major abiotic stresses prevailing in arid and semiarid areas such as the southern high plains of the United States. In these areas, both declining quality of groundwater and cultivation practices have resulted in increased accumulation of salts in the root zone. The occurrence of excessive salts in the root zone is detrimental for plant growth and economic yield. Recently, biochar has received a great consideration as a soil amendment to mitigate the detrimental impacts of salinity stress. However, the effectiveness of biochar to mitigate the salinity stress depends on the feedstock type, pyrolysis temperature and time, soil type and properties, and plant species. Therefore, a pot experiment in a greenhouse was conducted to 1) examine the effects of salinity stress on physiology, shoot and root growth, and yield of eggplant (Solanum melongena L.), and 2) evaluate the potential of hardwood biochar and softwood biochar to mitigate the damaging effects of salinity stress on eggplant. The experiment was conducted in a split-plot design with three salinity levels of irrigation water [S0 (control, 0.04 dS·m−1), S1 (2 dS·m−1), and S2 (4 dS·m−1)] as main-plot factor and three biochar treatments [B0 (control, non-biochar), Bh (hardwood biochar), and Bs (softwood biochar)] as subplot factor with four replications. Results showed that stomatal conductance (gS) and photosynthesis rate decreased significantly, while leaf temperature and electrolyte leakage increased significantly with increase in irrigation water salinity levels. Root growth (root length density and root surface area density), shoot growth (plant height, stem diameter, and leaf area), and yield of eggplant declined with increase in levels of salinity stress. Biochar application helped to enhance gS and photosynthesis rate, and to decrease leaf temperature and electrolyte leakage in leaf tissues of plants. This resulted in better root growth, shoot growth, and fruit yield of eggplant in treatments amended with biochar than non-biochar (control) treatment. There was no significant difference in the effect of two types of biochars (hardwood and softwood biochar) on physiology, root growth, shoot growth, and yield of eggplant. Therefore, it can be concluded that softwood and hardwood biochars could be used to minimize the detrimental impacts of salinity stress in eggplant.

Effect of nanoparticle on growth, biochemical and anatomical characteristics of moringa plant (Moringa oleifera L.) under salinity stress condition

Two pot experiments were carried out at the Experimental Farm of the Agricultural Botany Department, Faculty of Agriculture, Al-Azhar University (Assiut branch), Assiut, Egypt, during two successive seasons of 2018 and 2019. The main aim of this study was to find out the effect of both of foliar application with some growth promoters (using nanotechnology) i.e., zinc, iron, copper oxide nanoparticles at 50, 100 and 150 mgl-1 of each and silica nanoparticles at 20, 40 and 60 mgl-1 as well as salinity stress level of irrigation water at 9000 mgl-1 individually and their interactions on growth, biochemical and anatomical characteristics of Moringa oliefera L. plant. The results showed that individually salinity stress level of irrigation water at 9000 mgl-1 decreased all studied vegetative growth parameters of moringa plant i.e., plant height (cm), stem diameter (cm), leaves number plant-1, leaf area plant-1 as well as root, stem and leaves dry weights plant-1 compared with the control. The same trend was obtained in photosynthetic pigments content (total chlorophyll) as well as the studied anatomical characteristics of root section (i.e., root diameter of V.C and length of xylem arch), stem section (i.e., stem diameter, O of V.C, length of V.B in the stem) and Leaf blade section (i.e., upper epidermis thickness, lower epidermis thickness and mesophyll tissue for leaflet) at 50 days of Moringa oliefera leaves compared with unstressed plant. On other hand, salinity stress level at 9000 mgl-1 resulted in increasing antioxidant activity as well as total phenolic contents at 60 days of Moringa oliefera leaves compared with unstressed plant. Data also indicated that the individually foliar application treatments with Zinc, Iron, Copper oxide nanoparticles at 50, 100, 150 of each and Silica at 20, 40, 60 mgl-1 nanoparticles increased studied vegetative growth as well as anatomical characteristics, chemical compositions, photosynthetic pigments (total chlorophyll), antioxidants activity and total phenolic contents of moringa plant compared with the control treatment. In this respect, Silica nanoparticles at 60 mgl-1 followed by zinc and iron oxide at 150 mgl-1 nanoparticles of each were the most effective treatments, respectively. Finally , Based on these results, it could be concluded that the foliar application with nanoparticles gave the highest Valois of morphological, chemical compositions and anatomical characteristics its that reduce the harmful effects of salinity stress of Moringa oliefera L. plant specially at silica 60 mgl-1,. Data recorded that this results using it under the same field conditions (Assiut governorate, Egypt).

Sewage Sludge Impacts on Yields, Nutrients and Heavy Metals Contents in Pearl Millet–Wheat System Grown Under Saline Environment

Salinity prompts heavy metals accumulation and adversely affects nutrient contents in soil and plants, thereby reducing crop yields. The assessment of domestic sewage sludge (SS) under saline conditions to boost crop productivity has become crucial. A field trial was conducted for two consecutive years (2017–2019) with three irrigation levels [canal water (0.35 dS m−1), I1; 8 dS m−1, I2; and 10 dS m−1 saline water, I3]; and five fertilization levels [control, F1; SS (5 t ha−1), F2; SS (5 t ha−1) + 50% RDF, F3; SS (5 t ha−1) + 75% RDF, F4; and RDF, F5]. The results revealed that treatment I3 (10 dS m−1) reduced the grain yield of pearl millet and wheat by an average of 31.2 and 32.6%, respectively, compared to I1 (0.35 dS m−1). However, among fertilizer treatments, F5 obtained significant highest grain and straw yields statistically at par with F4 treatment. Also, in the context of nutrients content in crops, a similar trend has been reported. In the addition, with the usage of saline irrigation (EC 8 and 10 dS m−1) and SS (5 t ha−1), the availability of heavy metals in crops and soil had increased (p = 0.05). The soluble ions in soil increased with increasing salinity levels of irrigation water. The extractability series of heavy metals were: Pb > Co > Ni > Cr > Cd. The addition of SS, however, recorded a higher concentration of DTPA-extractable metals in soil over control. The heavy metals content did not exceed toxicity levels in soil and plants. Hence, the incorporation of SS (5 t ha−1) resulted in saving 25% mineral fertilizers and, also combined use of SS with mineral fertilizers proved to be economically beneficial for crop production.

Potentially toxic element (PTE) levels in maize, soil, and irrigation water and health risks through maize consumption in northern Ningxia, China

BackgroundIndustrial and agricultural activities result in elevated levels of potentially toxic elements (PTEs) in the local environment. PTEs can enter the human body through the food chain and pose severe health risks to inhabitants. In this study, PTE levels in maize, soil, and irrigation water were detected, and health risks through maize consumption were evaluated.MethodsMaize, soil, and irrigation water samples were collected in northern Ningxia, China. Inductively coupled plasma-optical emission spectrometry was applied to determine the contents of six PTEs. Bioaccumulation factor was used to reflect the transfer potential of a metal from soil to maize. Health risks associated with maize consumption were assessed by deterministic and probabilistic estimation. Sensitivity analysis was performed to determine variables that pose the greatest effect on health risk results.ResultsThe levels of Pb and Cr in maize exceeded the standards, while the PTE levels in soil and irrigation water did not exceed the corresponding standards. The bioaccumulation factor values of the six PTEs in maize were all lower than 1 and followed the order of Cd > Zn = As > Cr > Cu > Pb. The hazard index (0.0986) was far less than 1 for all inhabitants implying no obvious non-carcinogenic risk. The carcinogenic risk value was 3.261 × 10− 5, which was lower than the maximum acceptable level of 1 × 10− 4 suggested by United States Environmental Protection Agency (USEPA). Females were at greater risk than males, and the age group of below 20 years had the greater risk among all the groups evaluated. Approximately 0.62% of inhabitants exceeded the level for non-carcinogenic risk, while 8.23% exceeded the level for carcinogenic risk. The As concentration and daily intake of maize contributed 35.8, and 29.4% for non-carcinogenic risk results as well as 61.0 and 18.5% for carcinogenic risk results.ConclusionsMaize was contaminated by Pb and Cr, whereas the associated soil and irrigation water were not contaminated by PTEs. Inhabitants would not suffer obvious harmful health risks through maize consumption. Arsenic level and daily intake of maize were the most sensitive factors that impact health risks.

Micronutrients accumulation under pearl millet-wheat cropping system in response of salinity levels amended with sewage sludge

Aim: The present study was undertaken to evaluate the effect of sewage sludge and saline water irrigation on micronutrients concentration in pearl millet- wheat cropping system. Methodology: The trial was conducted during 2017-2019 at Soil Research Farm, CCS Haryana Agricultural University, Haryana in a factorial random block design with three replications. There were three salinity levels of irrigation water, i.e., canal water (0.35 dS m-1), 8 and 10 dS m-1 EC of saline water; and five fertilization levels, i.e., control (no fertilizer), sewage sludge(5 t ha-1), SS (5 t ha-1) + 50% RDF, SS (5 t ha-1) + 75% RDF and 100 % RDF. However, sewage sludge was applied in Rabi seasons only. Results: Based on pooled analysis of two years, micronutrients (Fe, Mn and Cu) concentration in grain and stover/straw of pearl millet and wheat crops significantly reduced on application of saline water irrigation (ECiw 8 and 10 dS m-1) whereas, Zn concentration was non significantly affected with salinity levels. However, highest concentration of Fe, Mn and Cu was recorded with canal water irrigation. There was a significant increase in micronutrients (Fe, Mn and Cu) concentration in both crops with sewage sludge application in comparison of RDF and control treatments but in case of zinc treatment SS (5 t ha-1) + 75% RDF and 100% RDF were at par with each other. Among treatments, significantly higher concentration of micronutrients was recorded with SS (5 t ha-1) + 75% RDF treatment being at par with SS (5 t ha-1) + 50% RDF. Interpretation: Salinity affects micronutrient availability adversely. However, zinc content was not affected significantly. In such case, sewage sludge application may prove a feasible option that serves as a supplement of nutrients as well as sorting out the problem of dumping waste.

Quality of 'Tainung no. 1' papaya in function of production times and irrigation managements

This study evaluates the quality of 'Tainung no. 1' papaya cultivated by partial rootzone drying (PRD) at summer and winter seasons, in Mocambinho, Jaíba, Minas Gerais, Brazil. The ten treatments resulted from the combination of four PRD forms and one with full irrigation (FI), without water deficit, during two production seasons. The experiments were set up in an entirely randomized. The treatments using PRD were based on the reduction of the calculated irrigation water level by 50%, alternating the side of the irrigated row with only one lateral line irrigation per row. The alternating frequencies (AF - changing of sides) were 7, 14 and 21 days and a fixed side without alternation. The FI was composed per two lateral lines per row of plants. The quality and sensorial evaluations were performed on ripe fruits (totally yellow peel). Papayas produced in summer were larger, firmer, with an orange and more acidic pulp. Irrigation managements interfered with the purchase intention and the sensorial attributes of fruits produced in summer and winter. Consumers liked the overall appearance and the color of papaya pulp produced in the summer, with the exception of PRD AF 7 days. The acceptance of texture and flavor varied depending on irrigation management.

Raised beds modulate physiological responses, yield and water use efficiency of wheat (Triticum aestivum L) under deficit irrigation

Irrigation water scarcity has now become one of the main constraints that influences global crop production. The potential reduction in Egypt’s Nile share and the current degree of deterioration of surface and ground water will certainly increase the severity of the water shortage problem in Egypt. Raised bed planting systems under deficit irrigation could be a partial solution to compensate for the negative effect of water stress on wheat plants. Two field experiments were managed successively in 2016/17 and 2017/18 to study the influence of irrigation water levels at 100% (DI0), 80% (DI20), and 60% (DI40) crop evapotranspiration (ETc) and three different plantation systems (flat planting (PS1), 60 cm raised beds (PS2), and 120 cm raised beds (PS3) on growth, photosynthetic efficiency, yield, and irrigation crop water productivity (I-WP) of wheat plants. The results revealed that yield reduction caused by deficit irrigation can be remunerated by the raised-bed planting method. When averaged over both seasons, the highest grain and straw yield of wheat plants was recorded under PS2 and PS3 compared with PS1, while there were no significant differences between PS2 and PS3. Raised beds (PS2 and PS3) combined with DI0 followed by DI20 significantly increased growth characteristics, leaf chlorophyll contents and their efficiency, stomatal conductance, yield and its components compared with PS1 combined with DI40. The highest value of I-WP (1.61 and 1.54 kg m−3) was obtained under DI20 combined with PS2 and PS3, respectively. Therefore, under both land- and water-limiting conditions, such as in the current Egyptian situation, raised beds could be considered a potential planting technique for improving the growth and productivity of wheat under deficit irrigation (DI20) by conserving 20% (1050 m3 ha−1) of the water needed for wheat production.