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Soilless Agriculture a New and Advanced Method for Agriculture Development: an Introduction

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Abstract Agriculture out of the soil is to use any means that will cultivate and plant development without entering the soil as a mediator for agriculture, where cultivated plants in isolation from the soil as long as the system used allows to strengthen the plants and provide water needed for growth and nutrients as it is the system followed for growing plants in the natural soil environment with irrigated nutrients intravenously instead of plain water and may be used a solid material such as gravel, sand, peatmoss, perlite and vermiculite in some cases as supporting mediators. Agriculture outside of soil is including hydro agriculture (Hydroponics), aqua agriculture (Aquaponics), aerobic agriculture (Aeroponics) as well as agriculture using supportive mediators. Benefits of soilless cultures include the reservation of cultivated lands for main crops; save not less than 90% of irrigated water; use nearly recycled fixed amount of water; most vegetable crops succeed and give the highest productivity in soilless agriculture than the ordinary agriculture; It can be run in various places such as balconies, roofs of buildings, various greenhouses and lands unsuitable for cultivation; the provision of fertilizer materials, where it’s used rationed amounts calculated accurately nutrients according to the plant requirements; Ease of dealing with plants and ease of conducting the required protection operations against various pests; Despite the increase in the constituent unit cost of soilless culture, but the large amount of production offset this cost in a short time. Soilless culture is a method of cultivation of new and advanced and requires us to search for human cadres have the ability to qualify for this work and is a rare, unfortunately. Keywords: Hydroponics; Aquaponics; Aeroponics; Soilless cultures; Agriculture
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Research Article
Volume 3 Issue 2 - January 2017
DOI: 10.19080/ARTOAJ.2017.03.555610
Agri Res & Tech: Open Access J
Copyright © All rights are reserved by K A El-Kazzaz
Soilless Agriculture a New and Advanced Method for
Agriculture Development: an Introduction
K A El-Kazzaz1 and AA El-Kazzaz2*
1Agricultural Engineer, Head of Hydro Valley Company, Cairo, Egypt
2Department of Plant Biotechnology, National Research Centre, Egypt
Submission: December 19, 2016; Published: January 04, 2017
*Corresponding author: AA EI-Kazzaz, Department of Plant Biotechnology, National Research Centre, 12622, Dokki, Giza, Egpyt,
Tel: ; Email:
Introduction
Although several published works on cultivation plants
in soils, few of these concentrate on planting plants in soilless
cultures. The presented work is an overview of the systems of
agriculture out of the soil. However, soilless agriculture offer a way
to overcome the shortage of the normal amount of water needed
to grow plants. Agriculture without soil, in fact, historically dates
back to several hundred years BC since the civilization of ancient
Egyptian, the Chinese and other cultures [1]. The Aztecs started
a method of suspended gardens based on hydroponics at Lake
Tenochtitlan during the 10th and 11th centuries [2,3]. There are
various techniques of soilless agricultures have being recently
used. Such techniques are including Hydroponics, Aquaponics,
Aeroponics as well as agriculture using supportive mediators.
The soilless agricultures can be accessed on various kinds of
places such as balconies, roofs, greenhouses and lands unsuitable
for cultivation. Such kinds of agriculture operate under control
conditions in order to obtain higher productivity and higher
incomes. Despite the rise within the constituent cost of soilless
culture, however the massive quantity of production offset this
value in an exceedingly short time. Soilless culture could be a
technique of cultivation of recent and advanced and needs to go
looking for human cadres have the power to qualify for this work
and could be a rare, sadly. In this regard, it will be reviewed these

Historical steps of soilless agriculture
As it was remembered in introduction, soilless agriculture
was used and recorded in several ancient civilizations but
no information was recorded about it. However, the earliest
published work on growing terrestrial plants without soil was
the 1627 book, Sylva Sylvarum by Sir Francis Bacon, father of
        
Agri Res & Tech: Open Access J 3(2): ARTOAJ.MS.ID.555610 (2017) 001
Abstract
Agriculture out of the soil is to use any means that will cultivate and plant development without entering the soil as a mediator for agriculture,
where cultivated plants in isolation from the soil as long as the system used allows to strengthen the plants and provide water needed for growth
and nutrients as it is the system followed for growing plants in the natural soil environment with irrigated nutrients intravenously instead of
plain water and may be used a solid material such as gravel, sand, peatmoss, perlite and vermiculite in some cases as supporting mediators.
Agriculture outside of soil is including hydro agriculture (Hydroponics), aqua agriculture (Aquaponics), aerobic agriculture (Aeroponics) as
 
 
soilless agriculture than the ordinary agriculture; It can be run in various places such as balconies, roofs of buildings, various greenhouses and
lands unsuitable for cultivation; the provision of fertilizer materials, where it’s used rationed amounts calculated accurately nutrients according
to the plant requirements; Ease of dealing with plants and ease of conducting the required protection operations against various pests; Despite
the increase in the constituent unit cost of soilless culture, but the large amount of production offset this cost in a short time. Soilless culture is
a method of cultivation of new and advanced and requires us to search for human cadres have the ability to qualify for this work and is a rare,
unfortunately.
Keywords: Hydroponics; Aquaponics; Aeroponics; Soilless cultures; Agriculture
How to cite this article: K A El-Kazzaz, A A El-Kazzaz. Soilless Agriculture a New and Advanced Method for Agriculture Development: an Introduction.
Agri Res & Tech: Open Access J. 2017; 3(2): 555610. DOI: 10.19080/ARTOAJ.2017.03.555610
002
Agricultural Research & Technology: Open Access Journal
However, Robert Boyle, the Irish scientist, in 1666 had been
        
roots submerged in water. In 1699, John Woodward published his
water culture experiments with spearmint and found that plants
in less-pure water sources grew better than plants in distilled
water. Mineral nutrient solutions for soilless culture of plants

von Sachs and Wilhelm Knop through experiments conducted at

water culture system was made in 1929 by Professor William
Frederick Gericke of the University of California at Berkeley. The
term ‘‘hydroponics’’ was coined by Gericke 1937 to describe
the growing of crops with their roots in a liquid medium.
Moreover, in 1940 Gericke wrote the book, Complete Guide to
Soilless Gardening. However, two others of plant nutritionists
at the University of California named Dennis R. Hoagland and
        
named Hoagland solution used for hydroponics until now. Since,
 
a refueling stop for Pan American Airlines, Hydroponics was
used to grow vegetables for the passengers. Hydroponics was a
necessity on Wake Island because there was no soil, and it was
prohibitively expensive to airlift in fresh vegetables. In the 1960s,
Allen Cooper of England developed the Nutrient Film Technique.
In recent decades, many companies world widely are appearing
and strongly working in soilless agriculture. Moreover, NASA
has done extensive hydroponics research for their Controlled
Ecological Life Support System (CELSS) [1-6].
Designation and function of soilless culture
Soilless culture is a man-made suggests that of providing
plants with support and a reservoir for nutrients and water. In
this regards, Savvas et al. [6], reported that Soilless culture can be

as a rooting medium, in which the inorganic nutrients absorbed

oldest technique for soilless culture may be a vessel of water
during which inorganic chemicals melted (nutrient solution) to
produce all of the nutrients that plants need. Typically is known
as solution culture or water culture.
The function of soilless cultivating method is stimulating
plant growth while controlling the quantities of water, mineral
salts and most important, dissolved oxygen. The basic concept
is quite simple. When roots are suspended in moving water,
they absorb food and oxygen rapidly. If the oxygen content
          
saturated with oxygen, plant growth will accelerate. Therefore,
the grower’s task is to balance the combination of water,
nutrients, and oxygen, with the plan’s needs, in order to
maximise yield and quality. For the best results, a few important
parameter need to be taken into account; temperature, humidity
         
genetic make-up. Essentially this is what any conscientious
gardener would do. Agriculture outside of soil is including hydro
agriculture (Hydroponics), aqua agriculture (Aquaponics),
aerobic agriculture (Aeroponics) as well as agriculture using
supportive mediators. However, In Soilless culture plants did not
need soil but they need to be supplied with minerals Nitrogen
(N), Potassium (K), Phosphorous (P), Calcium (Ca), Magnesium
(Mg), Sulphur (S), Iron (Fe), Manganese (Mn), Copper (Cu), Zinc
(Zn), Molybdenum (Mo), Boron (B), Chlorine (Cl) and vitamins
also they need water, light, carbon dioxide, oxygen at their root
zone. It is an art.
Types of soilless cultures
There are two main types of soilless culture; closed soilless
culture and open soilless culture.
Closed soilless culture type: In closed soilless frameworks
the dissolved supplements are recycled and the supplement
concentrations are observed and balanced in like manner.
Keeping the supplement adjust in such hydroponic frameworks
is a test and the dissolved supplements must be examined
and dissected in any event once every week. The dissolved
supplements must be balanced by results. If there is not oversaw
appropriately, the dissolved supplements may escape of the
balance. Closed soilless frameworks incorporate both basic and
advanced soilless culture frameworks.
Open soilless culture type: In open soilless frameworks a
new dissolved supplements is involved for every irrigation cycle.
The dissolved supplements are normally conveyed to the plants
utilizing the dripping framework. In open soilless frameworks a

keep supplement adjust in the root zone. Every soilless culture
utilizes just the substrates and dribble frameworks are has a
place with open soilless culture. However, there is a drip system
used as closed system in case of use reservoir for recirculating
the nutrient solution.
Soilless culture systems that divided from both
soilless culture types
The following systems are belonging to closed soilless
culture in brief
Hydro agriculture (Hydroponics):
        
don’t need soil, but they do need the vitamins and minerals that
soil can provide for them. Plants also need light, water, carbon
dioxide and oxygen at the root zone. In hydroponics, plants are
    
they are fed a solution containing a perfected mix of primary,
secondary and micro-nutrients. Almost any kind of plant can
be grown hydroponically, including veggies, herbs, fruits and
        
growers.
Hydroponics provides an advantage over soil growing for
        
climate conditions can be controlled in a greenhouse. Because
How to cite this article: K A El-Kazzaz, A A El-Kazzaz. Soilless Agriculture a New and Advanced Method for Agriculture Development: an Introduction.
Agri Res & Tech: Open Access J. 2017; 3(2): 555610. DOI: 10.19080/ARTOAJ.2017.03.555610
003
Agricultural Research & Technology: Open Access Journal
their roots do not need to reach for nutrients, the plants can
        
larger because of so many available nutrients and not having
to waste time growing extensive root systems. This makes the
yields bigger. The nutrient solution also keeps the same amount
    

things makes hydroponics plants more productive than soil
growing plants. Many farmers in various places are beginning to
switch over to hydroponics for all of these reasons. The concern
about water use is also big reason hydroponics is becoming
        
         
some of the kinds of hydroponics mainly used, but any person
can put his own design according to his need and the kind of
plants according to the main target and the aim of hydroponics

Figure 1: Shows the wick system.
Wick system: The wick system (Figure 1) is the simplest of
all types of hydroponic systems. That’s because traditionally it
doesn’t have any moving parts, thus it doesn’t use any pumps or
electricity. However, the wick is the connecting part between the
potted plant and food solution in the existing reservoir. Because
it doesn’t need electricity to work, it’s also quite useful in places
where electricity can’t be uses, or is unreliable. The wick system
           

This type of hydroponic system is also often used by teachers in
classrooms as experiments for kids. In wick system the plants
are cultivated in substrate.

(Figure 2) is recirculated design to run highly oxygenated
dissolved nutrients continuously over the roots of plants
through a set of channels, typically grown in baskets hanging in
a PVC pipe. The solution is pumped from a holding tank, through
irrigators at the top of every sloping pipe and the run-off from
the bottom of the channels is returned to the tank. Thus, the
nutrient solution is continuously recycled. It is possible to make

 
reservoir of nutrients that would remain in the event of a power
           

     
plants that have small root balls such as lettuce, strawberries,
and herbs.
Figure 2: Shows the Nutrient Film Technique (NFT).
Water culture or deep water culture (DWC): Water
culture or deep water culture is the straightforward form of
        
        
supplied by an air pump that runs continuously. A water culture
  
boxes, ice boxes, Concrete basins or in engraved basins covered
        
continuously in contact with the nutrient solution, there is no
risk of damage to plants in the event of a power outage or stop
the air pump. The most convenient plants in this system are
Lettuce, strawberries, and herbs grow particularly well in this
system.
Figure 3: Shows the deep water culture system.
Drip system: Drip hydroponic system (Figure 4) is at least
two containers, one on top or higher than the other. Plants
are located in the top container, while the nutrient solution is
in the bottom container. The nutrient solution is pumped up
to drips located by the stem of each plant with a water pump,
and an aquarium air stone is used to oxygenate the water. The
      
the bottom container. Typically both the water and air pumps
run continuously with this type of system. A crop of almost any
plant will grow well with this system. Plants with large root balls
are particularly suited to drip systems. However, the plants are
grown in supportive mediators.
How to cite this article: K A El-Kazzaz, A A El-Kazzaz. Soilless Agriculture a New and Advanced Method for Agriculture Development: an Introduction.
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Figure 4: Shows Drip system (DWC).
        
another inexpensive type of hydroponic setup. The setup is very
similar to the drip system, where there are two containers, the
one on top containing the plants in pots with substrate, and
the one on the bottom containing the nutrient solution. Rather
than the nutrient solution being passed slowly to drippers at the
stem of each plant, the nutrients are pumped in large volumes
  
determines the height of the nutrients, typically to where the
roots begin at the base of the stem, with excess liquid being
        
        

the grow tray periodically. When the pump is switched off, all of
the nutrients are siphoned out of the grow tray via the pump line.
The emptying period allows for oxygen to reach the roots, and
for this reason an air stone is not absolutely required for ebb and
   
well with this type of system. Plants with large root balls are also

Figure 5: Shows the Ebb and ow (Flood and Drain) system.
Aeroponic systems
The aeroponics system is belong to closed soilless culture
system (Figure 6) is probably the most high-tech type of
        
used as reservoir for nutrient solution and the plants above
the reservoir cover (polystyrene or other material) must be
supported or hanged through holes in the expanded cover, hence
the roots hang in the air under the reservoir cover and are misted
with nutrient solution found in the reservoir by stressful pump
to cover all area around the root with nutrient solution mist. The
misting is usually done every few minutes around the hanged
roots. Because the roots are exposed to the air, the roots will dry
out rapidly if the misting cycles are interrupted. A timer controls
the nutrient pump much like other types of hydroponic systems,
except the aeroponics system needs a short cycle timer that runs
the pump for a few seconds every couple of minutes. However,
the chamber must be lightless materials from everywhere, so
that the roots are in darkness functionally good also to inhibit
algal growth that impedes the growing plants and pollute the
system.
Figure 6: Clear aeroponics misting system with modication.
          
sealed root chambers. The plants are grown in holes in panels
of expanded polystyrene or other material. The plant roots
suspended in midair beneath the panel and enclosed in a
spraying box. The box sealed so that the roots are in darkness
(to inhibit algal growth) and in saturation humidity. A misting
system sprays the nutrient solution over the roots periodically.
The system normally turned on for only a few seconds every 2-3
     
solution aerated.
        
framework is high pressure aeroponics frameworks don’t
generally utilize a water pump because of the various cycle
(on/off) times required. They as a rule comprise of a two sided
tank with an elastic divider. The supplement arrangement is in
one side and air in the other. At that point an air compressor is
utilized to pressurize the tank. A water line from the supplement
arrangement side races to the clouding heads, and a solenoid
is utilized to open and close a valve in the water line at exact
times utilizing a cycle clock. The genuine aeroponics framework
utilizes high pressure (60-90 psi). The second framework is low
pressure aeroponics frameworks (soakaponics) are what the
vast majority are alluding to when they say aeroponics. Low
pressure frameworks utilize standard submersible water pumps,
yet at the same time require a decent measure of water weight
or the water will simply stream out of the sprinkler/mister
heads. The more sprinkler heads you’re utilizing, the more water
pressure you will require. Sadly submersible pumps don’t give a
psi rating to look at. They just give you gallons every hour (GPH)
How to cite this article: K A El-Kazzaz, A A El-Kazzaz. Soilless Agriculture a New and Advanced Method for Agriculture Development: an Introduction.
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Agricultural Research & Technology: Open Access Journal
and head tallness, and GPH is a measure of volume, not pressure.
         
It takes pressure to pump water up, so the more GPH it can
pump higher, the more water pressure it will have. In any case,
the vast majority allude to low pressure splashing frameworks
as aeroponics frameworks as well. The third framework is
Ultrasonic foggers that make a fog in aeroponic frameworks.
While they do make a fog with a little water bead measure, there
is next to no genuine dampness in the fog/mist. The fog made
from ultrasonic foggers likewise tends to drop to the base of the
holder. Ensuring the roots is totally secured by the fog constantly.
Another issue with utilizing foggers is that the plates tend to stop
up with mineral form. The main plates that have appeared to
       
They can once in a while be cleaned utilizing white vinegar, or
dilute and pH, and wiping them off with a Q-tip. A few producers
have joined utilizing ultrasonic foggers alongside the low weight


Figure 7: Clears the target steps of Aquaponics culture with
hydroponics deep water culture (Can be replaced by NFT
system or Media lled beds system or all systems together can
be worked).
Aquaponics is a system of aquaculture (Figure 7) in which
         
grown in tanks with combination of hydroponics in which
plants are grown in water in a symbiotic environment [9-
11]. In aquaculture, the aquatic animal’s excretions are raised
and accumulated in the water, increasing toxicity according to
ammonia foundation as toxic byproducts for aquatic animals;
hence, the aquaculture must be cleaned from that toxic material.
In an aquaponics system, water from an aquaculture system is
passing to hydroponics system where the toxic by-product are
broken down by Nitrifying bacteria that live on the surface of
the grow bed media initially into nitrites and subsequently into
nitrates, which are utilized by the plants as nutrients, and the
water is then cleaned and passing back to the aquaculture system.

        
nitrates, which are usable by the plants. As existing hydroponic
and aquaculture cultivating procedures constitute the foundation
for all aquaponics frameworks, the size, complication, and sorts
of foods grown in an aquaponics framework can differ as much as
any framework found in either particular cultivating discipline.
These are the most commonly used type of aquaponics systems;

 
           
and plants grow in the rock media. This style of system can be

   
     
is a commonly used hydroponic method, but is not as common
in aquaponics systems. In NFT systems, nutrient rich water is

in small plastic cups allowing their roots to access the water and
absorb the nutrients. NFT is only really suitable for certain types
of plants, generally leafy green vegetables, however, larger plants
will have root systems that are too big and invasive, or they
become too heavy for the lightweight growing gutters. 3- Deep

of the water allowing the roots to hang down into the water. This
can be done in a number of ways. This method is one of the more
commonly practiced commercial methods. DWC can be done
    

        
  
and extract the nutrients. However, this system is considered as
closed soilless culture whereas a recirculating system for the
nutrient solution is occurred.
Figure 7 clears the target steps of Aquaponics culture with
hydroponics deep water culture (Can be replaced by NFT system
          
worked).
Substrate culture (Growth medium)
Figure 8: Clears some of the used substrates in soilless cultures.
Growth medium is the substitute for soil in soilless culture
systems. In this system, a solid medium provides support for the
plants. The functions of growth medium are to provide the roots
How to cite this article: K A El-Kazzaz, A A El-Kazzaz. Soilless Agriculture a New and Advanced Method for Agriculture Development: an Introduction.
Agri Res & Tech: Open Access J. 2017; 3(2): 555610. DOI: 10.19080/ARTOAJ.2017.03.555610
006
Agricultural Research & Technology: Open Access Journal
with oxygen bring the water and dissolved nutrients in contact
with roots via irrigation system through the media, allowed to
run to waste to recirculate the solution through the system and
to steady the plants as supportive mediators so that they do not
         
growth medium are consisting of inorganic (natural; expanded
clay, glasswool, gravel, perlite, pumice, rockwool, sand, sepiolite,
vermiculite, volcanic tuff and zeolite or synthetic; foam mats,
hydrogel and plastic foam) or organic (bark, coconut coir, coco

chips) [12].
The substrate culture systems divided according to
drainage procedure into the following two major systems [13].
As remembered before, in most soilless cultures that used
substrates without reservoir for recirculating the nutrient
solution are belong to open soilless cultures, therefore, more
care about the feeding the plants must be taken because the
irrigation water with the supplements dominantly lost. The
open substrate culture seems to be more promising due to its

where hydroponics is applied commercially, open hydroponics
cultivation systems have created pollution problems resulting in
a consequent transition to closed systems. The closed substrate

  
needs to be developed for each crop [16,17].
Properties of substances used in soilless culture: There
are many stuffs are used for building the growing systems
for soilless culture, such as asbestos, aluminum, concrete,
corrugated sheets, polyethylene, polypropylene, polystyrene
foam, PVC, steels and any material that comes to mind. All these
stuffs must have sustainability characteristics [12].
      
the systems:      

       
2- No damaging volatilization of damps or substances. 3-
Resistance to vapor that used for sanitation, UV radiation and
pesticides. 4- Ensure rewind materials to suppliers for recycling.

solutions (inert). 7- Also, Metallic materials must be coated with
weatherproof materials against interact with any solid materials,
liquid or gaseous.
    
hydroponics as a technique of soilless culture is using only water,
with no substrate. This is true for NFT or Aero-hydroponics,
which use no media, or just enough to act as a plant support. But
growers working with Drip Irrigation, Deep Channel NFT, or Ebb
and Flow, will use more or less supportive substrate depending
on the growing system they choose. Supportive substrates must
have the following properties [12]
1- Aeration and drainage. 2- Applicable in natural form
without need for processing. 3- Can be mined or produced by
      
Easy to use and Environmental and health hazards. 6- Free from
grit, heavy metals and radioactive pollutants and Cleanliness. 7-
Has constant quality (no decrease of physical properties during

10- Inert (no reaction with the nutrients). 11- Low cost. 12-
         
or destroyed without hazard. 16- Resistant for sterilization
several times without structural quality change. 17- Pest free.

and water to air ratio.
Another essential aspect to keep in mind is the close
relationship between the supportive substrate and the irrigation
cycles applied whereas some of them will retain much more
moisture than others. Many supportive substrates are in the

Plant Necessities
Growth demands
Many factors, such as nutrition, light, heat, air, pH and salinity
affect plant growth, whether it was developing in the soil or soil-
free systems. In agriculture without soil Systems, nutrition and
water are permanently available to the plants, whether inside or
outside doors and therefore the plants never stressed. However,
in outdoor, the sun light and air are obtainable but for indoor
       
lights, Metal halide lamps or sodium vapor lamps must be used.
All soilless culture systems must provide available oxygen using
good air circulation at the root zones to keep them alive. Healthy
roots which are white in color are responsible for absorption
of nutrients and water for growing the plant. However, it must
be good air circulation for the indoor systems around the plant
leaves to carry out the photosynthesis. However, root zone must
be worm enough to keep the root zone to 20-22 C° as possible to
prevent ant disorder can be done for the cultivated plants.
Nutrient solution
The success or failure of agriculture without soil depends
on the existence of balanced nutrient solutions and appropriate
for all stages of plant growth. Agricultural fertilizers are
sold through stores that sell agricultural products and must
choose the right fertilizer for soilless cultures that contain all
13 elements necessary for plant growth. It is crucial to follow
instructions of the dilution rate recommended on the label and
to test the recommended solution to be sure the pH is between
           

development, some elements in the nutrient solution will be
depleted more quickly than others. Therefore, it is appropriate
to measure the lack of elements of the farming system without
soil every two weeks, and to provide this shortage, also, make
How to cite this article: K A El-Kazzaz, A A El-Kazzaz. Soilless Agriculture a New and Advanced Method for Agriculture Development: an Introduction.
Agri Res & Tech: Open Access J. 2017; 3(2): 555610. DOI: 10.19080/ARTOAJ.2017.03.555610
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Agricultural Research & Technology: Open Access Journal
sure that the nutrient solution is kept at the original volume. It
must compensate the lack of water as the result of in the output
cultivated plant consumption and as a result of evaporation
during cultivation time in the system. Due to lack of water in the
system, the concentration of nutrients is increase and can harm
the root system and its function, therefore, it must compensate
         
the nutrient solution to its original concentration. Be sure to use
nutrients designed for Hydroponics in a Hydroponic system. The
composition of elements in nutrients designed for soil is very
different from that for Hydroponics because soil grown plants
get most of these elements from the soil. With Hydroponics there
is no soil to get the elements from, so the two are very different
in composition because they are not designed to be a complete
plant food and they may not water-soluble. For example,
Nitrogen in the form of urea is not immediately available to a
plant in hydroponics because urea is not soluble in water. For this
reason Nitrogen must be delivered in its Nitrate form in order to
       
when it comes to nutrients is the nutrient solution temperature.
The roots of plants grow underground in nature and to duplicate
what they would receive in nature it is very important to keep
the root zone to 20 - 22 °C. That’s not to say if the nutrient temp

as close to 20 – 22 °C as you can. Plants with nutrient tempters

turning yellow and falling off, damaged fruits and a lack of new

Water Quality

without soil is water availability and quality. There are many
sources for water availability from lakes, rainwater, rivers and
underground reservoirs or from other treatments. However,
water must be of high quality free of pathogens as determinant
factors for the success of agriculture without soil [19].
Water Disinfection

a rapid dispersal of soil-borne pathogens by the recirculating
nutrient solution. To eliminate these pathogens, several
disinfection methods can be used and the followings are some
of them:
Ozone treatment
         
       
its function is to destroy bacteria, viruses and odors. An ozone
supply of 10 g/h/m3 water with an exposure time of 1 h is

UV disinfection
Another way to disinfect the drain water is the use of UV-
radiation. Ultra-violet radiation (or UV) is a proven process for
disinfecting water, air or solid surfaces that are microbiologically
contaminated. For eliminating bacteria and fungi an energy dose
  
cm2 is recommended. The advised dosage of 100mJ/cm2 to
control Fusarium gave adequate control at 14% transparency.
       
at 4% transparency, more than 174mJ/sq.cm was required.
For Fusarium control, the grower has the option of diluting the
water, or increasing the UV radiation [21-23].
Heat treatment
When heat treatment is applied, a solution is heated for
 
all pathogens are killed [24]. A disadvantage of heat treatment
is the consumption of gas. Also warm drain water contains less
oxygen.

For several years commercial growers have used a slow





hand operated or fully automatically.
Electrolysed water
In agriculture, the principle application is as a biocide,
signifying ‘life-executing’ specialist. It is utilized to split down
the foul develop in hydroponic lines that frequently contains
microorganisms, contagious spores and different organisms. It
is likewise utilized effectively for sterilization of seeds, blooms,
organic products, vegetables, hardware and packing materials.
Sooner rather than later it might be utilized for malady control
           

        
incorporate EW, hydrolysed water, electrically enacted water,
electrochemically delivered water, actuated water, dynamic

Hydrogen peroxide
Hydrogen peroxide treatment is a much less expensive

Be that as it may, it is a feeble oxidator. While the execution
is enhanced by including a powerless corrosive, it is still not
        
ppm) are expected to take out infections, however it was found
that a little rate of nematodes survived treatment (0.3%), and
          
peroxide items available have great impact for particular



  
How to cite this article: K A El-Kazzaz, A A El-Kazzaz. Soilless Agriculture a New and Advanced Method for Agriculture Development: an Introduction.
Agri Res & Tech: Open Access J. 2017; 3(2): 555610. DOI: 10.19080/ARTOAJ.2017.03.555610
008
Agricultural Research & Technology: Open Access Journal
pore measure of the membrane. They are costly and inclined
to gagging after some time. Remedy pre-treatment of supply
water is fundamental to expand the life span of membranes. The
      
should have been ready to treat no less than 20,000L/day and to

identical in expenses to synthetic treatment alternatives however
without the potential perils and without affecting on the nutrient
       

Chlorination
Chlorination is the most widely recognized type of cleansing
utilized by hydroponic cultivators. It is cheap and promptly
accessible. Chlorine is the only biocide that can be lawfully
      
normally known as ‘pool chlorine’, is the most widely recognized
disinfectant utilized by the producers. Without going into the
science, chlorine’s capacity to slaughter smaller scale living
beings comes about because of its solid oxidizing power and
the interruption of the working of the miniaturized scale living
        
execute all pathogens with which it comes into direct contact.
This is useful for cleaning water and recouped nutrient solution.
However, the used concentration must be acquired because if it
is used at highly strength, it will also attack and kill plant roots.
Moreover, it is not systemic so it won’t kill systemic pathogens

Advantages and Disadvantages of Soilless Cultures
There are published papers from few years ago that stating
the advantages and disadvantage of soilless cultures in the
following brief points [12].
Advantages of soilless cultures
Production augmentation: The application of soilless
culture approximately increases the yields as the result of the
precise control of the growth elements to the plants such as
nutrition, pH, oxygen, carbon dioxide, light and temperatures.
However, increasing the yield using soilless cultures will help the
offset the initial and any additional costs of the soilless cultures.
Soilless culture produced vegetables can be of high quality and
need little washing.
Water control: In most kinds of soilless culture the uses
of irrigation water are accurately controlled with extremely
less amount as compared with normal irrigation in the case of
traditional soil cultures. It save much needed labor and time for
checking, cleaning irrigation nozzles and frequent examination
of trippers which easily can be blocked by calcium carbonate
         
nutrient solution or by pretreatment of irrigation water and that
need more costs, labor and time.
Monitor of plant nutrition: The nutrition elements are
used as solution forms in accurate amounts as the plant needs
and not in Hugh amounts as in the normal plantation. In soilless
culture, the harmful elements to plants above certain dosages
can be kept within safe dosages. However, there is distribution
uniformity of nutrition elements only for all the plants in water
cultures. PH and E.C. of the nutrient solution can be controlled
according to the requirement of the crop and environmental

of normal soil cultures.
Purge practices: Soilless culture is occurred under
controlled conditions and that led to avoid spreading of weeds,
diseases and insects therefore no need for using the pesticides
     
and that mean less labour and less costs.
Monitor root surroundings: In soilless culture, it is easily
to control the surrounding environmental and root temperature
and supplying roots by oxygen.
Crop diversity: In soilless culture, the interval time between
crops is nearly null set because the absence of cultivation
operation as in soil cultivation therefore, multiple crops
cultivated per year and that mean increasing income.
Agriculture of land inappropriate: Agriculture without soil
provides an idealistic process for plant cultivation when there is
no appropriate land empty of pathogens and salinity is available.
    In soilless culture, all
cultural practices of soil cultivation such as soil sterilization,
weed control and others can be excluded in soilless culture and
that save the labor input and the needed time of work.
Disadvantages of soilless cultures
High capital investment: The initial cost of building the
system of soilless culture is high, but the fast and big yield

the beginning of the system if all things running ok.
The shortage of technicians and skilled labor: Agriculture
without soil suffers from a shortage of workers and trained
professionals.
The risk of Pathological Injuries: Morbidity in open
systems of soilless culture is few whereas in closed systems be
great and that need a big care and strong sanitation.
Prospective and Conclusion
Soilless cultures consider as a new developed technique for
agriculture development but it is not simple technique. However,
there is lack of technical background of the new technique
among growers and horticulturists in many countries and well
trained employs are needed. Moreover, most substrates are
internationally markets, so they are expensive. Therefore, it is
better to look locally about not expensive good substrates. The
growers can adept the soilless systems according to their needs,
the place of the system and according to their potential cash. The
system in any case need to take strong care and observation for
How to cite this article: K A El-Kazzaz, A A El-Kazzaz. Soilless Agriculture a New and Advanced Method for Agriculture Development: an Introduction.
Agri Res & Tech: Open Access J. 2017; 3(2): 555610. DOI: 10.19080/ARTOAJ.2017.03.555610
009
Agricultural Research & Technology: Open Access Journal
the parameters needed for the good growth of the plants such
as nutrient concentrations, light, oxygen around the plants root
zone, water quality, pH, disinfection, temperature of the solution
and more.
In conclusion, one might say that, there is extensive advance
has been made as of late in the improvement of monetarily
suitable soilless systems and there is a generally wide business
applications now in Countries that applied farming innovations.
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soilless growing methods. Acta Hort 396: 11-24.
     
       
(VPD) on greenhouse tomato fruit quality, foliar nutrient concentrations

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17.   

http://homehydrosystems.com/nutrients/nutrients_page.html
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
20. Runia WTh, (1994) Disinfection of recirculation water from closed

21. http://www.svarog-uv.org/drainage.htm
22. 
disinfection/
23. Nosir W (2016) New technique for rose production in soilless culture
     

24.          

   

26.       
technique to minimise the risks of spreading root-infecting pathogens

27.           
         
 
677.
http://www.hydroponics.com.au/disinfection-methods-an-
australian-perspective/
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How to cite this article: K A El-Kazzaz, A A El-Kazzaz. Soilless Agriculture a New and Advanced Method for Agriculture Development: an Introduction.
Agri Res & Tech: Open Access J. 2017; 3(2): 555610. DOI: 10.19080/ARTOAJ.2017.03.555610
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Agricultural Research & Technology: Open Access Journal
... In aggregate-based hydroponic systems like drip-irrigated or flood-and-drain methods, soilless growth material is employed [11]. The use of soilless growing media in hydroponic systems can boost crop yields when compared to conventional soil-based cultivation since quantities of water, nutrient and oxygen transfer are greater and can be simply optimized [12]. Crops grown indoor are protected from the outside environment and allow farmers to produce crops out of growing season, where lack of availability can result in greater prices and maximize profits [13]. ...
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Hydroponic system applications can help alleviate problems caused by changes in agricultural land usage. Many hydroponic researches have been carried out growing different plants, however their applicability in Sindh Pakistan requires some amendment. The research was conducted at Sindh Agriculture University Tandojam to build and analyse a hydroponic structure with a continuous nutrition system for cultivation of tomato. PVC pipes were used to construct the hydroponic system. Tomato plants were grown in hydroponic cups after transplanting for 15 days. The result revealed that EC and pH of water ranged between 1.23 to 2.76 dS/m and 5.32 to 6.92 respectively. The temperature of water varied between 18 to 24 ºC with an average value of 21 ºC. Ambient temperature and solar radiations varied between 21 to 26 ºC and 250 to 325 W/m2 respectively. Number of leaves per plant increased from 6 to 22 in 28 days after transplantation, and plant height increased from 15 to 32 cm. The total cost of construction of the hydroponic structure was 11,889/ PKR. The constructed hydroponic system proved to be a suitable technology for growing tomatoes in a protected environment with minimal space, fertilizer and water requirements.
... Plants can be hydroponically grown using different techniques, the most common being the nutrient film technique (NFT), deep water culture (DWC) and ebb-and-flow systems (e.g., [8]). In DWC, plants grow suspended on a platform on the surface of a nutrient solution stored in a basin or box with air supply. ...
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Hydroponic production raises economic and environmental issues related to the treatment, recovery or disposal of hydroponic wastewater, which can be rich in eutrophication-related nutrients, nitrogen (N) and phosphorus (P). Little focus has been put on the influence of the growth conditions on the N and P content in hydroponic wastewater, which is of uttermost importance when it is intended to reuse the wastewater for irrigation or other purposes with reduced impact on the environment. This study aimed to optimize an indoor non-recirculating deep-water culture (DWC) hydroponic system for lettuce (Lactuca sativa L. var. crispa) production, in terms of daily light integral (DLI) and volume of nutrient solution (NS) per plant, to maximize both the biomass production and the N and P removal, allowing for the wastewater to meet the criteria established for reusing in irrigation and minimizing the eutrophication impacts. A small-scale DWC hydroponic system with a fluorescent light fixture was built to study lettuce growth indoors for 35 days after transplanting (DAT). A first experiment was conducted under 14, 20 or 23 mol m−2 d−1 DLI and with 1.5 or 2 L of NS per plant. A pronounced inner leaf tip burn was observed, regardless of the volume of NS solution used, related to the unventilated conditions under high radiation. Total biomass was similar in all treatments and N and P removal was higher than 95% and 94%, respectively, at 35 DAT. Lettuces grown in 2 L of NS per plant exhibited higher average biomass. A second experiment was performed under 8, 10 or 12 mol m−2 d−1 DLI and with 2 or 3 L of NS per plant, making it possible to achieve healthy biomass at 35 DAT with higher water and light-use efficiency when compared to the first experiment. A DLI of 10 or 12 mol m−2 d−1 with 2 L of NS per plant and a DLI of 12 mol m−2 d−1 with 3 L of NS per plant made it possible to achieve both the best total biomass production and the highest N and P removal from water. Under those conditions, hydroponic wastewater complied with N and P criteria for reuse in irrigation, showing potential to be used as an alternative resource for agriculture and to minimize negative impacts on the environment.
... Soilless agriculture is a possible solution to the myriad of problems that are currently plaguing the agricultural sector. Not only does this approach save on both land and water, but it also has the added advantages of having better control over the nutrients and water that are delivered to the plants, thus making it easier to grow healthy plants consistently [13,14]. However, similar to conventional farming, soilless agriculture remains largely dependent upon harmful mineral fertilisers, although admittedly in smaller quantities [15]. ...
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A typically overlooked by-product of the anaerobic digestion process is the liquid diges-tate. The digestate is generally high in valuable nutrients like nitrogen, potassium, and phosphorus, which are essential for plant growth. This indicates that digestate can be an effective fertilizer. In this study, the pH of the anaerobic digestion process was controlled at three different set points (6, 7, and 8) for three different substrates (banana peels, cow dung, and red lentils) in order to determine the ammonium release characteristics at each set point. This was achieved by using two different setups ; one setup , named the daily dosing setup (DDS), incorporated pH corrections once a day, and the other setup , named the continuous dosing setup (CDS), corrected the pH every minute. It was discovered that a pH of 7 is the optimal set point for both ammonium release as well as the gas production rate. In terms of a comparative analysis between precise pH control being performed every minute and pH control that was performed once a day, there were differences present in the gas production profiles with the CDS providing enhanced rates compared to the DDS. However, there was a negligible difference in the ammonium release rate.
... Inconsistent results may be due to variable biotic and abiotic factors in the field that cannot be accounted for in a lab or greenhouse setting [4][5][6][7]. Vertical farming represents another avenue for technological advancement that can spur improvements in yield, cropping intensity (the number of crop harvests per year), and protection from pests and pathogens, while reducing nutrient and water usage [8][9][10][11]. In this paper, we consider vertical farming to be an indoor agriculture system that uses some level of controlled environment agriculture (CEA) in combination with soilless cultivation [12,13]. The soilless cultivation techniques used in vertical farming do not feature soil as a rooting medium; instead, roots come into direct contact with a nutrient solution either through complete or partial submergence (hydroponics and aquaponics) or periodic misting (aeroponics), or alternative substrates are used [14][15][16]. ...
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In this literature review, we discuss the various functions of beneficial plant bacteria in improving plant nutrition, the defense against biotic and abiotic stress, and hormonal regulation. We also review the recent research on rhizophagy, a nutrient scavenging mechanism in which bacteria enter and exit root cells on a cyclical basis. These concepts are covered in the contexts of soil agriculture and controlled environment agriculture, and they are also used in vertical farming systems. Vertical farming-its advantages and disadvantages over soil agriculture, and the various climatic factors in controlled environment agriculture-is also discussed in relation to plant-bacterial relationships. The different factors under grower control, such as choice of substrate, oxygenation rates, temperature, light, and CO 2 supplementation, may influence plant-bacterial interactions in unintended ways. Understanding the specific effects of these environmental factors may inform the best cultural practices and further elucidate the mechanisms by which beneficial bacteria promote plant growth.
... But if the solution is saturated with oxygen, plant growth will accelerate. Therefore, the grower's task is to balance the combination of water, nutrients, and oxygen, with the plan's needs, in order to maximize yield and quality (El-Kazzaz and El-Kazzaz, 2017). For the best results, a few important parameters need to be taken into account; temperature, humidity and CO2 levels, light intensity, ventilation, pH and the plant's genetic make-up. ...
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Soil based cultivation is now facing difficulties due to different man made reasons such as deforestation, industrialization and urbanization. Besides, sudden natural disasters, climate change and unlimited utilization of chemicals for agriculture purposes cause the depletion of land fertility and quality. With the advent of civilization, open field/soil-based agriculture is facing some major challenges; most importantly decrease in per capita land availability. Under such circumstances, in near future it will become impossible to feed the entire population using open field system of agricultural production only. That is why, scientists have developed a new alternative approach for cultivation system namely soil-less cultivation or hydroponics. Hydroponics is a soil-less culture technique in which plant can grow in a liquid or water solution. Hydroponic is a method of growing plants using mineral solution, in water, without soil. This method can be extremely helpful to countries that have poor land, which is not able to sustain agriculture. A large number of plants and crops or vegetables can grow by hydroponics culture The quality of yield, taste and nutritive value of end products is generally higher than the natural soil based cultivation. This cultivation is cost efficient, disease free and eco-friendly as well as getting popularity all over the world, both the developed and the developing countries.
... Agriculture outside of soil is including hydro agriculture (Hydroponics), aqua agriculture (Aquaponics), aerobic agriculture (Aeroponics) as well as agriculture using supportive mediators. Benefits of soilless cultures include the reservation of cultivated lands for main crops; save not less than 90% of irrigated water; use nearly recycled fixed amount of water; most vegetable crops succeed and give the highest productivity in soilless agriculture than the ordinary agriculture; It can be run in various places such as balconies, roofs of buildings, various greenhouses and lands unsuitable for cultivation; the provision of fertilizer materials, where it's used rationed amounts calculated accurately nutrients according to the plant requirements (Kazzaz et al., 2017). Soil is a natural body present on earth surface, which is formed by weathering of rocks, usually the most suitable and easy available medium for plant growth & development. ...
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Soil organic growing media for mat-type paddy seedling cultivation is considered the best option in the country for its capacity to help proficient and concentrated paddy plant production rapidly and uniformly. The primary goal of this review is to describe an examination of the effects of soil organic growing media on paddy seedling growth, development, quality, and quantity in mat-type paddy nurseries. According to a review of the research, paddy yield is higher for plants grown in multiple growing media than for plants grown in soil alone. Until relatively recently, the fundamental intention in choosing the growing materials in the growing media depended on performance and monetary opinions. Expanding dread over the ecological effects to evaluate more environmentally seedling growth materials. It is critical to recognize emphatic and environmentally sustainable growing materials for paddy seedling growing media in order to ensure sustained growth and development of soil organic cultivation. In this review, we describe the factors that influence the selection of growing media and remark on the most often employed soil organic elements in relation to them. We explain some of the renewable, elementary, and waste materials that have been investigated thus far, emphasizing their benefits and defiance. We explain a confirmation-based logic for a more compatible perspective to characterizing growing media and for a refiner discerning the practical and economic tangibility of modern soil organic growing media cultivation system for mat-type paddy seedling nurseries in response to the need for researchers to recognize promising new growing materials.
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In this study, microalgae culture ( Chlorella vulgaris ) and mint seedlings ( Mentha spp.) were combined in a hydroponic system to improve plant growth. Mint seedlings were grown both in microalgae-containing and in microalgae-free trial groups, and both groups were subjected to aerated and non-aerated conditions to show the effect of aeration and microalgae co-cultivation on the mint weight and height. The plant quality was also determined with color measurements of the mint leaves. The increase in the weight of the plants was the highest in microalgae-containing and aerated group (0.47 g) and the lowest in microalgae-free and non-aerated group (0.22 g). On the other hand, the variation in the plant height was not significant between the groups, the growth was lateral. The best quality mint leaves were also produced in microalgae-containing and aerated group. Our results have revealed the symbiotic life of the mint plant placed in the hydroponic system with microalgae and demonstrated improved mint growth and quality. This co-cultivation system is also potentially more environmentally friendly compared to growing microalgae and mint independently because of lower cost of aeration and mixing for microalgae cultivation, higher nutrient consumption efficiency, and reduced nutrient outflow.
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Soilless culture is emerging as a popular tool to grow agricultural and horticultural crops in open systems, closed systems, protected cultivation, vertical farming, and soil affected or stress-affected areas. The climatic factors and biometabolism are integrated in stimulating quality phenological growth and biochemical and physiological processes in soilless crop production. Soilless crop production (SCP) has immense potential to build a soilless green revolution and for sustaining crop production. Information on substrate and water based culture collected for the period from 1996 to 2022 is reviewed and analyzed in this work. The performance of crops in soilless culture improves morphological and physiological parameters compared with soil based cultivation. The distinct environmental factors positively influence soilless culture to exhibit cellular processes, biological processes, molecular processes, and the ecosystem in the crop. The impacts of ecological factors are more efficient in closed systems compared with open systems. The salient features of metabolites and biometabolism in substrate based media were identified with transcriptome analysis and found to be different compared with soil based cultivation. Developing simple nutrient formulations suited for soilless culture is essential to popularize this technology among marginal farmers.
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Hydroponic substrates so far have been based primarily on rockwool slabs. Against this background, investigations were made for the comparative evaluation of other substrate materials. Various organic, synthetic and mineral substrates - wood shavings, perlite, expanded clay aggregates in containers, recycled polyurethane-ether foam (PUR) slabs and rockwool slabs - were compared in experiments on the water and nutrient supply of cucumber. PUR and rockwool were also examined for the changes that occurred over two years of use. Several criteria were applied for substrate evaluation: - physical composition and its change, water consumption and amount of drainwater, nutrient balance, ecological quality and economic efficiency of substrates. Perlite and the organic substrates were found to be most suitable. Crop yields were also high in PUR, but water consumption and the amount of drainwater were quite high. An expanded clay substrate ranked last in the complex evaluation by all criteria. Further investigations will have to show whether many years of substrate use, differentiated nutrient supply and the inclusion of additional criteria would give a different rank order of the substrates under review.
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Rose flower is one of the most important cut- flowers, with the highest world production rate. Soilless culture has been increasingly popular in plant production worldwide in the past few decades. In two separate trials, the efficacy of Trichoderma harzianum, Anearobacillus migululanas, slow filtration, and UV ultraviolet (UV) treatment and sand filtration in eliminating Fusarium oxyporum, artificially added in the recirculating nutrient solution, was evaluated with Rosea hybrid plants grown in closed soilless systems. The dynamics of these fungi in the recirculating nutrient solution and in the sand filter was also investigated. T. harzianum, A. migululanas, UV treatment and Slow sand filtration were effective in reducing Fusarium root rot. However, slow sand filtration may be a more feasible disinfection method than UV because of lower costs of installation and maintenance and for its adaptability to a wide range of production systems. Moreover, these disinfection techniques can be successfully combined with the application of antagonistic microorganisms.
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Irrigation water from natural sources can be contaminated by fungi, Oomycota, or bacteria capable of causing serious diseases in seedlings in forest nurseries. Slow sand filtration (SSF) is a cost-effective technique for water decontamination prior to irrigation. The aim of the current study was to assess the effectiveness of SSF as a means of eliminating plant pathogens including Pythium sterilum, Fusarium solani, Xanthomonas campestris, Pseudomonas syringae pv. Syringae, and Rhizobium radiobacter from the lake water source used for irrigation. The applied SSF was effective in removing 80-90% of fungal and Oomycota inoculum as well as 70% of the bacteria in the investigated water. Therefore, SSF represents a practical step to lowering the use of pesticides during production of planting stocks in forest nurseries and a valuable element in an integrated plant protection system.
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Nutrient solution recirculation is often used to improve the use efficiency of mineral nutrients and to reduce the contamination of soils and ground water. Nevertheless, in soilless culture systems, sulfate ions may accumulate in the nutrient solution recirculating resulting in nutrient imbalances affecting both crop yield and quality. This study focused the long-term effects of sulfate concentration and VPD regime on plant growth, fruit quality, foliar mineral concentration and amino acid contents. From day 10 after transplanting, young tomato plants (Lycopersicon esculentum Mill, cv Trust) grown in NFT system were subjected to three sulfate concentrations in the nutrient solution (in mM; S1=5.2, S2=10.4, and S4=20.8), and two VPD treatments (in kPa; H1= 0.5 day/0.4 night, H2= 0.3 day/0.2 night). In the short run and for both VPD, tomato plants appeared to be tolerant to a large spectrum of SO4 concentrations. After 7 months of sulfate treatments, however, high levels of SO4 in the nutrient solution resulted in reduced foliar and fruit Ca content. Over the long run, Ca-S interactions and blossom-end rot were found. Correlations between sulfate treatments and foliar accumulation of amino acid content were established. Osmotic adjustment and anion-cation balance of tomato plants grown under high sulfate supply and various VPD regime is discussed.
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Considerable progress has been made recently in the development of media and economically viable soilless systems and a number of growers in different Mediterranean countries are using soilless culture commercially the extend of which varies, according to the level of education of the growers, the existing greenhouses' facilities and their level of organization. It is well known that soilless culture offers an alternative to soil culture when serious soil and water problems (i.e., soilborn pests, soil and water salinity, chemical residues in soil, water salinity, lack of fertile soil, water shortage, etc.), create difficulties in traditional soil-based production. The main advantages of soilless culture are the most accurate control over the supply of water, nutrients, pH, root temperature, etc., increase productivity due to easier and more accurate control of production factors, reduction of labour requirement, no need for soil sterilization, more crops per year, etc. On the other hand there are disadvantages like the higher initial capital investment for the construction and maintenance of the soilless setup, the risk of disease infections mainly in the recirculating (close) systems, occasionally the increase of labour requirement and the need for higher standard of management and skill compared to crops growing in soil. The margin of error in fertilizing and watering is reduced with soilless culture. Also of importance is the subject of environmental (soil & water) pollution by waste nutrients with the open systems which in less developed countries are more popular because they are easier to handle. Expansion of soilless culture in various Mediterranean countries at present and the years to come will depend in one hand on existing knowledge level of the growers, the organization and background facilities available as well as the degree of education and adoption of the new technological deveIopments on soilless culture. On the other hand, the speed of expansion in Mediterranean countries is greatly depended on the development of technically simple, reliable, with low cost, soilless systems, using if possible local low cost materials as substrates or pure hydroponic systems with the simplest automated systems which can be installed in structures of low investment, requiring low management techniques, in order to attract the attention and interest of the growers. The origins of soilless culture go back at least to the 17th century when, in 1666, Boyle attempted to grow plants in "vials containing nothing but water", and reported that one species (spearmint, Raphanza aquatica) survived for nine months. However, it was not until the 19th century that Liebig (1803-73) and Knop and Sachs (around 1859) initiated the systematic study of plant nutrition (Cooper, 1979).