Thermography Study of Moderate Electrical Conductivity and Nutrient Solution Distribution System Effects on Grafted Tomato Soilless Culture

In recent decades, salinity in the culture of tomatoes has been one of the most studied parameters. This study aimed to evaluate the effect of a moderate increase in salinity, fertigation distribution, and its control using thermography on a soilless culture of grafted tomato. A tomato crop (cv. Ramyle) grafted onto tomato rootstocks (cv. Emperor) was cultivated in coir crop units at the University of Almeria from Nov. 2012 to May 2013. A plot design subdivided with four blocks was used, with salinity values of 2.0 and 2.5 dS·m−1 in the main plots and fertigation distribution systems with either one (DD1) or four (DD4) drip manifolds in the subplots. The crop productivity was measured using total crop yield, commercial value, and size. The quality parameters in the fruits were not significantly affected. Thermographies were used to aid the control of differential transpiration exerted by salinity. The difference in salinity did not significantly affect the total or commercial production. However, despite being grafted plants, there was a statistically significant effect (P ≤ 0.05) on the fruit size distribution when the electrical conductivity (EC) of the nutrient solution was increased from 2.0 to 2.5 dS·m−1, with a lower production (16%) of large fruits and an increased production of smaller fruits. The DD4 system significantly increased large tomato production (22%) compared with DD1, and the quality parameters in the fruits were not significantly affected. As a result of the improvement in tomato size, the DD4 distribution system economically offset the required higher initial expenditure compared with the DD1 system. Thermography was revealed to be a robust, simple, and quick tool for diagnosing the effect of salinity on transpiration.

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Increased Electrical Conductivity in Nutrient Solution Management Enhances Dietary and Organoleptic Qualities in Soilless Culture Tomato

HortScience ◽

10.21273/hortsci12026-17 ◽

2017 ◽

Vol 52 (6) ◽

pp. 868-872 ◽

Cited By ~ 18

Author(s):

Cristian Moya ◽

Eduardo Oyanedel ◽

Gabriela Verdugo ◽

M. Fernanda Flores ◽

Miguel Urrestarazu ◽

...

Keyword(s):

Electrical Conductivity ◽

Crop Productivity ◽

Poor Quality ◽

Soilless Culture ◽

Tomato Crop ◽

Tomato Production ◽

Greenhouse Tomato ◽

Commercial Yield ◽

High Yields ◽

Nutrient Solutions

Greenhouse tomato production is shifting to meet emerging consumer needs. Increasing environmental concerns have pressured growers to supply high-quality vegetables using sustainable production methods. The utilization of adapting fertigation to production conditions and/or nutrient solutions of moderately high conductivity seems promising in providing high yields of superior quality while limiting the emission of nutrients to the environment in greenhouse tomato crops. A tomato crop was grown in soilless culture with various levels of electrical conductivity (EC), 2.2, 3.5, and 4.5 dS·m−1, adjusting the final nutrient concentration and maintaining nutritional balance. The effect of nutrient solutions with moderately high EC on fertigation parameters and the emission of nutrients to the environment, total crop productivity, distribution of fruit sizes, and dietary and organoleptic qualities were measured. Nutrient solutions of moderately high EC decreased total and commercial yield, with an average reduction from 5% to 19% and 3% to 22%, respectively. A considerable decrease in extra large and large fruits, with an average reduction from 69% to 42%, was also observed. Nonetheless, dietary-related metabolites were significantly increased at the highest EC values: lycopene (6.3%), ascorbic acid (8.8%), total phenolics content (8.3%), and total antioxidant activity (11.1%). EC values of 3.5 and 4.5 dS·m−1 are not widely used in commercial production but are frequently measured in drainage solutions in open hydroponic systems and discarded solutions in closed systems, mainly because of the use of poor-quality water and the accumulation of excess nutrients.

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Effects of Fertigation Duration on the Pollution, Water Consumption, and Productivity of Soilless Vegetable Cultures

HortScience ◽

10.21273/hortsci.50.6.819 ◽

2015 ◽

Vol 50 (6) ◽

pp. 819-825 ◽

Cited By ~ 5

Author(s):

Miguel Urrestarazu ◽

Isidro Morales ◽

Tommaso La Malfa ◽

Ruben Checa ◽

Anderson F. Wamser ◽

...

Keyword(s):

Electrical Conductivity ◽

Plant Growth ◽

Root Growth ◽

Nutrient Solution ◽

Quality Parameters ◽

Solution Ph ◽

Root Volume ◽

Tomato Crop ◽

Growth Production ◽

Treatment Application

The management of water and nutrient ions, such as nitrate, has been studied extensively in recent decades. Increasingly efficient models have been developed for the use of water and nutrients through the automation of fertigation techniques. The application of a fertigation volume for a duration four times longer than applied on the control was evaluated. In Almería (Spain), one pepper crop and two tomato crops—with and without grafting—were grown between Oct. 2013 and June 2014 in a soilless system with a coir substrate. The effects on root growth, plant growth, production, and quality were measured. The following parameters for the fertigation of the nutrient solution and drainage were recorded: % drainage volume, electrical conductivity (EC) of the nutrient solution, pH, and concentration of nitrates and potassium. The absorption of potassium and nitrate, and the nitrate emissions of the drainage were estimated. The results showed an increase in the root volume and an improved distribution in the cultivation unit for the treatment application in the pepper crop. Slowing the applied fertigation improved the absorption of water and nitrates, and the production in the ungrafted tomato and pepper crops, while the grafted tomato crop was unaffected. Nitrate emissions were lower in the evaluated treatment of the pepper and ungrafted tomato crops. The fruit quality parameters were unaffected.

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Optimizing product quality in soilless culture systems (SCS)

Burleigh Dodds Series in Agricultural Science - Advances in horticultural soilless culture ◽

10.19103/as.2020.0076.14 ◽

2021 ◽

pp. 321-342

Author(s):

Pietro Santamaria ◽

◽

Barbara De Lucia ◽

Angelo Signore ◽

◽

...

Keyword(s):

Electrical Conductivity ◽

Product Quality ◽

Nutrient Solution ◽

Culture System ◽

Quality Parameters ◽

Soilless Culture ◽

Culture Systems ◽

Quality Profile ◽

Technical Factors ◽

Main Factors

In a soilless culture system (SCS), quality parameters of produce may be improved by better control of the environmental and technical factors involved. This chapter focuses on the main factors through which it is possible to influence and improve the quality profile of soilless horticultural produce. These include the composition, electrical conductivity, pH, temperature and management of the nutrient solution (NS). The chapter also discusses biofortification and harvesting methods.

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Organic characterisation tools for distribution system management

Water Science & Technology Water Supply ◽

10.2166/ws.2009.015 ◽

2009 ◽

Vol 9 (1) ◽

pp. 1-8 ◽

Cited By ~ 1

Author(s):

C. W. K. Chow ◽

Philipp Kuntke ◽

Rolando Fabris ◽

Mary Drikas

Keyword(s):

Water Quality ◽

Organic Carbon ◽

Distribution System ◽

High Performance ◽

Distribution Systems ◽

Management Strategies ◽

Molecular Size ◽

Quality Parameters ◽

Size Exclusion ◽

Treated Drinking Water

In this investigation, high-performance size exclusion chromatography (HPSEC) was used to characterise organic matter in treated drinking water at key sampling locations along two selected distribution systems (chlorinated and chloraminated). Other water quality parameters such as colour, UV254, dissolved organic carbon (DOC) and assimilable organic carbon (AOC) as measured by bacterial regrowth potential (BRP), were also determined. One of the aims of this work was to develop new tools to monitor organic character change along the distribution system in order to identify impacting factors and develop management strategies based on water quality change. This study used samples from two contrasting distribution systems with different disinfection regimes and organic characteristics together with samples generated from laboratory simulations. System 1 is a chlorinated distribution system and generally requires elevated chlorine dosage to meet the demand due to the high DOC level. System 2 is a chloraminated system with stable water quality, low DOC and low chloramine dose (mild oxidation). Molecular size distribution determination using HPSEC is a very informative technique in assessing treatment processes and in this study the appearance of a molecular peak at 1,700 Da that can be used as an indicator of biological activity in distribution systems was confirmed. The use of BRP values, for upstream and downstream samples in the distribution system, was found to be a good approach to assess biological impacts on water stability. The observed biological impact from the biofilms between the studied systems were particularly useful in confirming the organic characterisation results.

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Assessment of probable causes of chlorine decay in water distribution systems of Gaborone city, Botswana

Water SA ◽

10.4314/wsa.v45i2.05 ◽

2019 ◽

Vol 45 (2 April) ◽

Author(s):

Denis Nono ◽

Phillimon T Odirile ◽

Innocent Basupi ◽

Bhagabat P Parida

Keyword(s):

Water Quality ◽

Distribution System ◽

Distribution Systems ◽

Water Distribution ◽

Inorganic Compounds ◽

Quality Parameters ◽

Water Quality Parameters ◽

Biofilm Growth ◽

Reaction Rate Constants ◽

Chlorine Decay

Assessment of probable causes of chlorine decay in water distribution systems of Gaborone city, Botswana Gaborone city water distribution system (GCWDS) is rapidly expanding and has been faced with the major problems of high water losses due to leakage, water shortages due to drought and inadequate chlorine residuals at remote areas of the network. This study investigated the probable causes of chlorine decay, due to pipe wall conditions and distribution system water quality in the GCWDS. An experimental approach, which applied a pipe-loop network model to estimate biofilm growth and chlorine reaction rate constants, was used to analyse pipe wall chlorine decay. Also, effects of key water quality parameters on chlorine decay were analysed. The water quality parameters considered were: natural organic matter (measured by total organic carbon, TOC; dissolved organic carbon, DOC; and ultraviolet absorbance at wavelength 254, UVA-254, as surrogates), inorganic compounds (iron and manganese) and heterotrophic plate count (HPC). Samples were collected from selected locations in the GCWDS for analysis of water quality parameters. The results of biofilm growth and chlorine reaction rate constants revealed that chlorine decay was higher in pipe walls than in the bulk of water in the GCWDS. The analysis of key water quality parameters revealed the presence of TOC, DOC and significant levels of organics (measured by UVA-254), which suggests that organic compounds contributed to chlorine decay in the GCWDS. However, low amounts of iron and manganese (< 0.3 mg/L) indicated that inorganic compounds may have had insignificant contributions to chlorine decay. The knowledge gained on chlorine decay would be useful for improving water treatment and network operating conditions so that appropriate chlorine residuals are maintained to protect the network from the risks of poor water quality that may occur due to the aforementioned problems.

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Effect of irrigation with nutrient solutions mixed with treated wastewater on Asiatic lily ‘Brunello’ grown in a closed soilless culture

Acta agriculturae Slovenica ◽

10.14720/aas.2017.109.1.03 ◽

2017 ◽

Vol 109 (1) ◽

pp. 29

Author(s):

Ahmed Abdel-Nabi Al-Hammouri ◽

Khalid Al-Ghawanmeh ◽

Nabeel Bani Hani ◽

Nabeela Karam

Keyword(s):

Electrical Conductivity ◽

Nutrient Solution ◽

Dry Mass ◽

Treated Wastewater ◽

Soilless Culture ◽

Cut Flowers ◽

High Quality ◽

Greenhouse Study ◽

Potential Use ◽

Nutrient Solutions

A plastic greenhouse study was implemented to evaluate the potential use of treated wastewater for irrigation of Asiatic lily ‘Brunello’ grown in zeolite. Plants received the following treatments: a nutrient solution (N) alone, (N) mixed with treated wastewater (W) at rates of 3N:1W, 1N:1W and 1N:3W respectively. A closed system was used in which the drain solution was circulated for several days until its electrical conductivity reached 2.3 dS m-1, after which fresh irrigation solutions were used to start a second cycle of circulation. The results indicated that plants irrigated with (N) or 3N:1W solution had the longest stems (34.4 and 36.2 cm) respectively, peduncles and buds (about 4.5 cm), and the greatest shoot (3.4 and 3.8 cm) and bud mass (14.95 and 17.6 g) respectively. Plants irrigated with 1N:3W solution had the highest dry mass tissue content of K (3.06 g kg -1) and B (35.5 mg kg-1). Plants irrigated with 1N:1W or 1N:3W were inferior to other plants. It can be concluded that 1N:3W mixture may be used for production of high quality cut flowers of lily. Moreover, it is expected to save 3.4 litres m-2 of a nutrient solution and 1850, 347 and 1870 mg m-2 day-1 for N, P, and K respectively.

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Smart water grid: a review and a suggestion for water quality monitoring

Water Science & Technology Water Supply ◽

10.2166/ws.2021.342 ◽

2021 ◽

Author(s):

B. Bharani Baanu ◽

K. S. Jinesh Babu

Keyword(s):

Water Resources ◽

Real Time ◽

Distribution System ◽

Distribution Systems ◽

Water Distribution ◽

Water Distribution System ◽

Quality Parameters ◽

Smart Water ◽

Networking Protocols ◽

Smart Water Grid

Abstract Water is a valuable resource and an elixir of life. It is intimately linked to the living standards around the world. Reducing the water stress and conserving the resource is vital. It is the need of the hour to ameliorate the conventional water resources systems to monitor the water quantity and quality parameters continuously in real-time. Smart solutions play an important role in monitoring the system parameters and make on-site measurements. This paper focuses on Smart Water Grid, an ingenious way to monitor and preserve the quantity and quality parameters in real-time by deploying remote sensors in water distribution system. It presents a review of various sensors deployed, networking protocols used and cloud platforms employed in monitoring the water distribution system. The suitable networking protocols for the water distribution systems are suggested by analyzing various smart solutions. It also proposes an architecture for an IoT-based system to monitor the residual chlorine concentration in water distribution system. Smart Water Grid using Wireless Sensor Networks and the Internet of Things enables to monitor on-site conditions and generates alerts during abnormal conditions. It can enhance timely decision making which will help in managing valuable water resources more efficiently.

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Biological stability of drinking water in new York City

Water Science & Technology ◽

10.2166/wst.1998.0251 ◽

1998 ◽

Vol 38 (6) ◽

pp. 181-190 ◽

Cited By ~ 2

Author(s):

D. Jolis ◽

W. W. Faber ◽

V. Diyamandoglu

Keyword(s):

New York ◽

New York City ◽

Drinking Water ◽

Biological Activity ◽

York City ◽

Distribution System ◽

Distribution Systems ◽

Water Distribution ◽

Quality Parameters ◽

Drinking Water Distribution Systems

A study was carried out to determine the degree of biological activity in the drinking water supplied to New York City by the Croton and Catskill/Delaware systems, as measured by the Attached Growth Rate Estimate (AGRE) method. Also, possible relationships between AGRE results and standard water quality parameters were examined. The AGRE results for both the systems ranged between 0 and 0.5 d−1, indicative of biologically stable water. These results suggest that excessive bacterial growth in the New York City distribution system would be rare. The Croton results were temperature and alkalinity dependent. The Catskill/Delaware results revealed that growth rates decreased with travel time in the distribution system. These differences emphasize the complexity of biological activity monitoring in drinking water distribution systems.

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Irrigation Strategies for Greenhouse Tomato Production on Rockwool

HortScience ◽

10.21273/hortsci.43.2.484 ◽

2008 ◽

Vol 43 (2) ◽

pp. 484-493 ◽

Cited By ~ 2

Author(s):

Uttam K. Saha ◽

Athanasios P. Papadopoulos ◽

Xiuming Hao ◽

Shalin Khosla

Keyword(s):

Weight Loss ◽

Root Growth ◽

Water Content ◽

Water Use ◽

Nutrient Solution ◽

Irrigation Schedule ◽

Marketable Yield ◽

Tomato Crop ◽

Tomato Production ◽

Greenhouse Tomato

To address the concern that irrigation provides sufficient water to match the crop needs, while not impeding oxygen availability to the roots, we conducted an experiment to develop suitable irrigation schedule(s) for greenhouse tomato (Lycopersicon esculentum Mill.) on rockwool. The experimental treatments incorporated the electrical conductivity (EC) of the nutrient solution in the rockwool slab (slab-EC) along with the water content (WC) in the rockwool slab (slab-WC) as the irrigation decision-making variables. They were: slab-WC ≤ 70% or slab-EC ≥ 1.4× normal or more (T1), slab-WC ≤ 70% or slab-EC ≥ 1.7× normal or more (T2), slab-WC ≤ 80% or slab-EC ≥ 1.4× normal or more (T3), slab-WC ≤ 80% or slab-EC ≥ 1.7× normal or more (T4), and the combined weight loss (WL) 700 g or more (T5) and WL 500 g or more (T6), in which “normal” means the feed solution EC as recommended in the seasonal fertigation schedule for a spring–summer tomato crop. The data on early-season marketable yield, total seasonal marketable yield, and fruit grades indicated the superiority of treatments T1, T2, and T6 over T3, T4, and T5. Better root growth was observed with T1, T2, and T6 and this was also associated with minimized nutrient solution leaching; furthermore, these plants had an abundance of coarse and fine roots, higher photosynthesis and transpiration, higher marketable yield, and a higher water use efficiency. Our results thus established that irrigation based on either a slab water content 70% or less or a 500-g weight loss is the best strategy for rockwool-grown greenhouse tomatoes in the spring–summer season. A variation in slab-EC between 1.4 and 1.7× normal, at a slab-WC of 70% or less, would have no significant effect on root growth, water use, marketable yield, or fruit grades.

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Salinity tolerance of tomato fertigated with different K+/Ca2+ proportions in protected environment

Revista Brasileira de Engenharia Agrícola e Ambiental ◽

10.1590/1807-1929/agriambi.v25n9p620-625 ◽

2021 ◽

Vol 25 (9) ◽

pp. 620-625

Author(s):

Francisco de A. de Oliveira ◽

Francisco I. G. Paiva ◽

José F. de Medeiros ◽

Mikhael R. de S. Melo ◽

Mychelle K. T. de Oliveira ◽

...

Keyword(s):

Electrical Conductivity ◽

Salt Stress ◽

Relative Yield ◽

Fruit Production ◽

Fruit Weight ◽

Tomato Crop ◽

Tomato Production ◽

Saline Waters ◽

Low K ◽

Nutritional Imbalance

ABSTRACT Adequate potassium and calcium nutrition is a strategy to reduce salt stress on tomatoes, as it reduces nutritional imbalance in plants. With the objective of evaluating tomato production using irrigation with saline waters and fertigation with different potassium-calcium proportions, an experiment was carried out in a protected environment in Mossoró, RN, Brazil. The experimental design used was randomized blocks, in a 5 x 4 factorial scheme, with four replicates. The treatments consisted of the combination of four electrical conductivity of nutrient solution (ECns) (1.75; 3.25; 4.75; and 6.25 dS m-1) combined with five ionic proportions (m/m) of potassium and calcium (F1 = 2.43:1; F2 = 2.03:1; F3 = 1.62:1; F4 = 1.30:1 and F5 = 1.08:1). The response variables were: number of fruits, mean fruit weight, fruit production per plant and relative yield. It was possible to identify satisfactory results of production when higher salinity was used. Fertigation with low K+/Ca2+ proportions intensifies the effect of salinity on tomato crop.

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