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Currently hydroponic cultivation is gaining popularity all over the world because of efficient resources management and quality food production. Soil based agriculture is now facing various challenges such as urbanization, natural disaster, climate change, indiscriminate use of chemicals and pesticides which is depleting the land fertility. In this article various hydroponic structures viz. wick, ebb and flow, drip, deep water culture and Nutrient Film Technique (NFT) system; their operations; benefits and limitations; performance of different crops like tomato, cucumber, pepper and leafy greens and water conservation by this technique have been discussed. Several benefits of this technique are less growing time of crops than conventional growing; round the year production; minimal disease and pest incidence and weeding, spraying, watering etc can be eliminated. Commercially NFT technique has been used throughout the world for successful production of leafy as well as other vegetables with 70 to 90% savings of water. Leading countries in hydroponic technology are Netherland, Australia, France, England, Israel, Canada and USA. For successful implementation of commercial hydroponic technology, it is important to develop low cost techniques which are easy to operate and maintain; requires less labour and lower overall setup and operational cost.
Content may be subject to copyright.
Hydroponics as an advanced technique for vegetable
production: An overview
Received: 03 July 2018; Accepted: 29 November 2018
Currently hydroponic cultivation is gaining popularity all over the world because of efficient resources
management and quality food production. Soil based agriculture is now facing various challenges such
as urbanization, natural disaster, climate change, indiscriminate use of chemicals and pesticides which
is depleting the land fertility. In this article various hydroponic structures viz. wick, ebb and flow, drip,
deep water culture and Nutrient Film Technique (NFT) system; their operations; benefits and limitations;
performance of different crops like tomato, cucumber, pepper and leafy greens and water conservation
by this technique have been discussed. Several benefits of this technique are less growing time of crops
than conventional growing; round the year production; minimal disease and pest incidence and weeding,
spraying, watering etc can be eliminated. Commercially NFT technique has been used throughout the
world for successful production of leafy as well as other vegetables with 70 to 90% savings of water.
Leading countries in hydroponic technology are Netherland, Australia, France, England, Israel, Canada
and USA. For successful implementation of commercial hydroponic technology, it is important to develop
low cost techniques which are easy to operate and maintain; requires less labour and lower overall
setup and operational cost.
Key words: Nutrient Film Technique (NFT), water conservation, nutrient management, Hydroponic market
Journal of Soil and Water Conservation 17(4): 364-371, October-December 2018
ISSN: 022-457X (Print); 2455-7145 (Online); DOI: 10.5958/2455-7145.2018.00056.5
1Research Associate, 2,4Scientist, 3JRF, 5Director, Defence Institute of High Altitude Research (DIHAR), DRDO, C/o 56 APO,
Leh-Ladakh, 194101, Jammu and Kashmir
*Corresponding author Email id:
Hydroponics is a technique of growing plants
in nutrient solutions with or without the use of an
inert medium such as gravel, vermiculite, rockwool,
peat moss, saw dust, coir dust, coconut fibre, etc.
to provide mechanical support. The term
Hydroponics was derived from the Greek words
hydro’ means water and ponos’ means labour and
literally means water work. The word hydroponics
was coined by Professor William Gericke in the
early 1930s; describe the growing of plants with
their roots suspended in water containing mineral
nutrients. Researchers at Purdue University
developed the nutriculture system in 1940. During
1960s and 70s, commercial hydroponics farms were
developed in Arizona, Abu Dhabi, Belgium,
California, Denmark, German, Holland, Iran, Italy,
Japan, Russian Federation and other countries.
Most hydroponic systems operate automatically to
control the amount of water, nutrients and
photoperiod based on the requirements of different
plants (Resh, 2013).
Due to rapid urbanization and industrialization
not only the cultivable land is decreasing but also
conventional agricultural practices causing a wide
range of negative impacts on the environment. To
sustainably feed the world’s growing population,
methods for growing sufficient food have to evolve.
Modification in growth medium is an alternative
for sustainable production and to conserve fast
depleting land and available water resources. In the
present scenario, soil less cultivation might be
commenced successfully and considered as
alternative option for growing healthy food plants,
crops or vegetables (Butler and Oebker, 2006).
Agriculture without soil includes hydro agriculture
(Hydroponics), aqua agriculture (Aquaponics) and
aerobic agriculture (Aeroponics) as well as
substrate culture. Among these hydroponics
techniques is gaining popularity because of its
efficient management of resources and food
production. Various commercial and specialty
crops can be grown using hydroponics including
leafy vegetables, tomatoes, cucumbers, peppers,
strawberries, and many more. This article covers
different aspect of hydroponics, vegetables grown
in hydroponics system and global hydroponic
Hydroponic system are customised and
modified according to recycling and reuse of
nutrient solution and supporting media.
Commonly used systems are wick, drip, ebb-flow,
deep water culture and nutrient film technique
(NFT) which are described below (Fig. 1).
Wick System
This is simplest hydroponic system requiring
no electricity, pump and aerators (Shrestha and
Dunn, 2013). Plants are placed in an absorbent
medium like coco coir, vermiculite, perlite with a
nylon wick running from plant roots into a reservoir
of nutrient solution. Water or nutrient solution
supplied to plants through capillary action. This
system works well for small plants, herbs and spice
and doesn’t work effectively that needs lot of water.
Ebb and Flow system
This is first commercial hydroponic system
which works on the principle of flood and drain.
Nutrient solution and water from reservoir flooded
Fig. 1. Diagram of various structures of hydroponic system
366 SHARMA et al. [Journal of Soil & Water Conservation 17(4)
through a water pump to grow bed until it reaches
a certain level and stay there for certain period of
time so that it provide nutrients and moisture to
plants. Besides, it is possible to grow different kinds
of crops but the problem of root rot, algae and
mould is very common (Nielsen et al., 2006)
therefore, some modified system with filtration unit
is required.
Drip system
The drip hydroponic system is widely used
method among both home and commercial
growers. Water or nutrient solution from the
reservoir is provided to individual plant roots in
appropriate proportion with the help of pump
(Rouphael and Colla, 2005). Plants are usually
placed in moderately absorbent growing medium
so that the nutrient solution drips slowly. Various
crops can be grown systematically with more
conservation of water.
Deep water culture system
In deep water culture, roots of plants are
suspended in nutrient rich water and air is provided
directly to the roots by an air stone. Hydroponics
buckets system is classical example of this system.
Plants are placed in net pots and roots are
suspended in nutrient solution where they grow
quickly in a large mass. It is mandatory to monitor
the oxygen and nutrient concentrations, salinity and
pH (Domingues et al., 2012) as algae and moulds
can grow rapidly in the reservoir. This system work
well for larger plants that produce fruits especially
cucumber and tomato, grow well in this system.
Nutrient Film Technique (NFT) system
NFT was developed in the mid 1960s in
England by Dr. Alen Cooper to overcome the
shortcomings of ebb and flow system. In this
system, water or a nutrient solution circulates
throughout the entire system; and enters the growth
tray via a water pump without a time control
(Domingues et al., 2012). The system is slightly
slanted so that nutrient solution runs through roots
and down back into a reservoir. Plants are placed
in channel or tube with roots dangling in a
hydroponic solution. Although, roots are
susceptible to fungal infection because they are
constantly immersed in water or nutrient. In this
system, many leafy green can easily be grown and
commercially most widely used for lettuce
Recently hydroponic technique is becoming
popular because this is clean and relatively easy
method and there is no chance of soil-borne disease,
insect or pest infection to the crops thereby reducing
or eliminating use of pesticides and their resulting
toxicity. Besides, plants require less growing time
as compared to crop grown in field and growth of
plant is faster as there is no mechanical hindrance
to the roots and the entire nutrient are readily
available for plants. This technique is very useful
for the area where environmental stress (cold, heat,
dessert etc) is a major problem (Polycarpou et al.,
2005). Crops in hydroponic system are not
influenced by climate change therefore, can be
cultivated year-round and considered as off season
(Manzocco et al., 2011). Further, commercial
hydroponic systems are automatically operated and
expected to reduce labour and several traditional
agricultural practices can be eliminated, such as
weeding, spraying, watering and tilling (Jovicich
et al., 2003). Hydroponics saves large amount of
water as irrigation and other kind of sprays is not
needed and water logging never occurs. The
problem of pest and disease can be controlled easily
while weed is practically non-existent. Higher
yields can be obtained since the number of plants
per unit is higher compared to conventional
Although soil-less cultivation is an advanta-
geous technique but some limitations are
significant. Technical knowledge and higher initial
cost is fundamental requirement for commercial
scale cultivation (Resh, 2013). Plant in a
hydroponics system is sharing the exact same
nutrient, and water borne diseases can easily spread
from one plant to another (Ikeda et al., 2002). Hot
weather and limited oxygenation may limit
production and can result in loss of crops.
Maintenance of pH, EC and proper concentration
of the nutrient solution is of prime importance.
Finally, light and energy supply is required to run
the system under protected structure.
Plant nutrients used in hydroponics are
dissolved in water and are mostly in inorganic and
ionic forms. All 17 elements essential for plant
growth are supplied using different chemical
combinations. Hoagland’s solution is used as most
common nutrient solutions for hydroponic systems.
Cooper’s 1988 and Imai’s 1987 nutrient solutions
were also used for growing leafy vegetables,
tomatoes and cucumber. Proper pH and EC of the
nutrient solution is very essential and should be
maintained properly for optimum plant
Optimum range of EC and pH values for
different hydroponic crops is shown in Table 1.
Ideal EC range for hydroponics for most of the
crops is between 1.5 and 2.5 dS m-1. Higher EC will
prevent nutrient absorption due to osmotic
pressure and lower level severely affect plant health
and yield. So, appropriate management of EC in
hydroponics technique can give effective tool for
improving vegetable yield and quality (Gruda,
2009). As an example, yield of tomato under
hydroponic system increased as EC of nutrient
solution increased from 0 to 3 dSm-1 and decreased
as the EC increased from 3 to 5 dS m-1 due to
increase of water stress (Zhang et al., 2016). Level
of EC @1.5, 2 and 3 dS m-1 at vegetative, middle
vegetative and generative phase, respectively had
increased crop height, fruit number and pepper
fresh weight.
In a nutrient solution, pH determines the
availability of essential plant elements. Optimum
pH range of nutrient solution for development of
plants is 5.5 to 6.5 (Trejo-Tellez and Gomez, 2012)
for most species but some can differ from this range.
Once the plants grows, it will change the
composition of nutrient solution by depleting
specific nutrients more rapidly than others,
removing water from the solution and altering the
pH by excretion of either acidity or alkalinity. Wang
et al. (2017) found that mixture of three (HNO3,
H3PO4 and H2SO4) acids was much more effective
than only single acid for maintaining an optimal
solution pH of 5.5 to 6.5. Change in pH may cause
nutrient imbalance and plant will show some
deficiency or toxicity symptoms. Hence, care is
required for maintaining optimum pH, EC and
nutrient level in hydroponic solution. Crops such
as vegetables, spices, flower and ornamentals,
medicinal plants, fodders and up to some extent
cereals can be raised through soil less hydroponic
technique and is mentioned in Table 2.
A large number of plants and crops or
vegetables can grow by hydroponics system.
Quality of produce, taste and nutritive value of end
products is generally higher than the natural soil
based cultivation. Various experimental findings
outlines that leafy greens (lettuce, spinach, parsley,
Table 2. Various species of plants grown under soil less hydroponic system
Type of crops Name of the crops
Cereals Rice, Maize
Fruits Strawberry
Vegetables Tomato, Chilli, Brinjal, Green bean, Beet, Winged bean, Bell pepper, Cucumbers,
Melons, green Onion
Leafy vegetables Lettuce, Spinach, Celery, Swiss chard, Atriplex
Condiments Coriander leaves, Methi, Parsley, Mint, Sweet basil, Oregano
Flower / Ornamental crops Marigold, Roses, Carnations, Chrysanthemum
Medicinal crops Indian Aloe, Coleus
Fodder crops Sorghum, Alfa alfa, Bermuda grass, Carpet grass
Table 1. Optimum range of EC and pH values for hydro-
ponic crops
Crops EC (dSm-1)pH
Asparagus 1.4 to 1.8 6.0 to 6.8
African Violet 1.2 to 1.5 6.0 to 7.0
Basil 1.0 to 1.6 5.5 to 6.0
Bean 2.0 to 4.0 6.0
Banana 1.8 to 2.2 5.5 to 6.5
Broccoli 2.8 to 3.5 6.0 to 6.8
Cabbage 2.5 to 3.0 6.5 to 7.0
Celery 1.8 to 2.4 6.5
Carnation 2.0 to 3.5 6.0
Courgettes 1.8 to 2.4 6.0
Cucumber 1.7 to 2.0 5.0 to 5.5
Egg plant 2.5 to 3.5 6.0
Ficus 1.6 to 2.4 5.5 to 6.0
Leek 1.4 to 1.8 6.5 to 7.0
Lettuce 1.2 to 1.8 6.0 to 7.0
Pak Choi 1.5 to 2.0 7.0
Peppers 0.8 to 1.8 5.5 to 6.0
Parsley 1.8 to 2.2 6.0 to 6.5
Rhubarb 1.6 to 2.0 5.5 to 6.0
Rose 1.5 to 2.5 5.5 to 6.0
Spinach 1.8 to 2.3 6.0 to 7.0
Strawberry 1.8 to 2.2 6.0
Sage 1.0 to 1.6 5.5 to 6.5
Tomato 2.0 to 4.0 6.0 to 6.5
368 SHARMA et al. [Journal of Soil & Water Conservation 17(4)
celery and atriplex etc) can be successfully and
easily grown in hydroponic systems. Lettuce and
spinach are most promising species to grow in
integrated hydroponics and aquaculture systems
because of its higher growth and nutrient uptake
Hydroponic research on lettuce, spinach and other leafy
Life cycle of hydroponic lettuce is very short
compared to traditionally grown lettuce.
Hydroponic lettuce can be harvested after 35 to 40
days of production. Lettuce can be successfully
grown in NFT system and more than 8 crops per
year can be grown efficiently in this system.
Horizontal and vertical hydroponic system was also
evaluated with different nutrient solutions for yield
optimization of lettuce (Touliatos et al., 2016).
Growing of lettuce in recirculating hydroponic
system at spacing of 50 plants m-2 significantly
increased yield and yield components (Maboko and
Plooy, 2009). Frezza et al. (2005) found that there is
significant difference in productivity and nitrate
content of lettuce in both soil less (floating system
and substrate culture) and soil culture however,
other traits like leaf area, dry weight and ascorbic
acid content were remain unaffected. In non
circulated and non-aerated system, air space
between nutrient solution and tank cover also
determines optimum lettuce yield. Another study
observed that marketable yield, shoot biomass and
leaf area index of lettuce grown in floating system
was not affected by nutrient solution composition
(Fallovo et al., 2009). In other experiment, it was
observed that both the hydroponic and organic
system perform equal in terms of lettuce yield,
quality and nitrate content, whereas, delayed
harvesting not only increased yield but lower down
nitrate level and reduced health hazards.
Besides lettuce, recently various hydroponic
experiments were conducted using spinach as
model crop. Ranawade et al. (2017) have compared
spinach yield in hydroponic, aquaponics and in
traditional system in which perlite (aquaponics)
and sphagnum moss (hydroponics) were used to
support the plants. The yield of the aquaponically
cultivated spinach was slightly more than
hydroponically cultivated spinach. The results of
Mwazi et al. (2010) showed that salinity has negative
impact on vegetative growth, but spinach has some
tolerance to saline water with 5 ppt. When spinach
grown in floating system, lack of aeration and
hypoxia was not severe enough to influence yield
and yield component as spinach is short duration
crop but quality somehow was affected (Lenzi et
al., 2011).
Hydroponic swiss chard when grown in gravel
film technique, plant density of 40 plant m-2 and 14
days of harvesting interval improved crop yield,
leaf area, biomass and leaf fresh weight (Maboko
and Plooy, 2013). Contrary to this, hydroponically
grown swiss chard, lettuce and sweet basil contain
high mineral content, high root/shoot ratio, low
level of nitrates, than grown in soil culture,
however, their nutrient uptake and yield was lower
(Bulgari et al., 2016). Effectiveness of rice husk
biochar alone and in combination with perlite as
substrates was also evaluated in NFT system for
growing crops like cabbage, red lettuce, dill and
mallow (Awad et al., 2017).
Tomato and pepper grown under hydroponics system
Many hydroponic systems can be used for
growing tomatoes but NFT and deep flow
technique (DFT) are commonly used system for
successful tomato production. Growing of tomato
in NFT system with regular recycling of nutrient
solutions improved growth, productivity and
mineral composition whereas, in NFT with
prolonged recycling of nutrient solution yield was
reduced (Zekki et al., 1996). Open and closed
hydroponic systems were evaluated for perfor-
mance of various cultivars of tomato and in closed
system higher marketable yield was obtained as
because of fruit cracking, yield was reduced in open
system (Maboko et al., 2011). Schmautz et al. (2016)
compared yield, quality and overall tomato plant
vitality in three different systems of hydroponics
(NFT, drip system and floating raft) system.
Researchers also investigate effects of plant
population, pruning and plant growth regulators
on yield and quality of hydroponically grown
pepper in various systems. Effectiveness of different
substrate (vermiculite + sand, Peat + perlite,
rockwool) were evaluated on growth and yield of
hydroponically grown green pepper and reported
that peat + perlite had most significant effect on
growing traits and yield of green pepper (Majdi et
al., 2012).
Besides tomato and pepper, cucurbits viz.
cucumber, cantaloupes are successfully grown in
various hydroponic systems. Experiments were
conducted on cucumber for optimization of salinity
level, EC and nutrients in various hydroponic. NFT
system was found to be most suitable for growth
and productivity of cantaloupe. Apart from
vegetables, nowadays strawberry and different cut
flowers are commercially grown under various
hydroponic systems.
As water becomes scarce and important as a
resource, the use of hydroponics and other water
saving technologies for crop production is needed
now and is poised to popularize in time.
Hydroponics uses substantially less water as
compared to the soil farming. In soil farming, most
of the water that we supply to the plants gets
leached deep into the soil and is unavailable to the
plants roots, whereas in hydroponics, plant roots
are either submerged in water or a film of nutrients
mixed in water is constantly encompassing the root
zone, keeping it hydrated and nourished. Water is
not wasted in this process, as it gets recovered,
filtered, replenished and recycled. Waste nutrient
solution can be used as an alternate water resource
for crop cultivation under hydroponic system (Choi
et al., 2012). Savings in irrigation water, fertilizer
and increase in vegetable and water productivity
under hydroponic system as compared to
conventional agriculture is depicted in Table 3. NFT
based hydroponics can reduce irrigation water
usage by 70% to 90% by recycling the run-off water.
It is possible to effectively grow high value, good-
quality vegetables under controlled hydroponic
conditions using 85 to 90% less water than tradi-
tional soil based production. Water sources from
groundwater or dam/river water commonly contain
factors that can influence plant yield and affect
plant condition, including salinity, dissolved solids
and pathogens. While some of these factors can be
beneficial to crops, others need to be minimised.
The Global Hydroponics Market has been
estimated to cross USD 21203.5 million in 2016. By
crop type, global hydroponics market includes
tomato, cucurbits, lettuce & leafy vegetables,
peppers and other food crops. Tomato forms the
largest market segment and it accounts for 30.4%
share of the global market, during 2018.
Hydroponics crop production is expected to be
more in tomatoes, lettuce and other leafy
vegetables. As the consumers are becoming
increasingly aware of the superiority of quality
greenhouse-grown vegetables, the demand for
hydroponics culture is rising in Europe and Asia-
Pacific. Europe is traditionally the largest market
that is implementing advanced techniques in
hydroponics. Asia-Pacific forms the second largest
market for hydroponics, which is expected to grow
at a steady pace. Leading countries in hydroponic
technology are Netherland, Australia, France,
England, Israel, Canada and USA. Dutch are the
world leader in commercial hydroponic having
total area of 13000 ha under tomato, capsicum,
cucumber and cut flowers (Netherlands
Department of Environment, Food and Rural
Affairs, NDEFRA) and this account 50% of the value
of all fruits and vegetables produced in the country.
Australian hydroponic production of vegetables,
herbs and cut flowers of system valued about 300-
400 million dollar which is approximately 20% of
the total values of vegetables and cut flower
production in Australia reported by Rural
Industries Research and Development Corporation
(RIRDC). Australia is the largest hydroponic lettuce
producers in the world, and having strawberry
cultivation is larger than USA and cut flower
production is almost equal to USA. Canada and
Spain are also expanding the area under
commercial hydroponic system. Japan has started
rice production by hydroponics technique to feed
the people (De Kreij et al., 1999). Israel grows large
quantities of berries, citrus fruits and bananas in
the dry and arid climate. Currently, demand of
hydroponics cultivation has been increased in all
the developing and developed countries (Trejo-
Tellez and Gomez, 2012). In India, several tracts of
wastelands having poor quality soil but plenty of
Table 3. Percentage of water and fertilizer consumption, vegetables yield percentage and the percentage of water productivity
for different hydroponic systems as compared with conventional farming system (AlShrouf, 2017)
Parameters Hydroponic system
Media soilless system Nutrient solution system
Open Closed Open Closed
% Irrigation water saving 80 85 85 90
% Fertilizer saving 55 80 68 85
% Productivity increase 100 150 200 250
% Water productivity 1000 1600 2000 3500
370 SHARMA et al. [Journal of Soil & Water Conservation 17(4)
water can be brought under hydroponics. Now a
day’s peoples in various big cities like Delhi,
Chandigarh, Noida and Bangalore are growing
some leafy greens and small herbs and spices on
their roof tops and balconies for fresh consumption.
The future for hydroponics appears more positive
today than any time over the last 50 years. The
startup costs to implement a hydroponic farm can
vary widely but, they are usually higher than soil-
based farming costs. Therefore, to foster the
hydroponics industry’s growth, it is important to
implement technologies that reduce dependence on
human labour and lower overall startup costs.
In recent years hydroponics is seen as a
promising strategy for growing different crops. As
it is possible to grow short duration crop like
vegetables round the year in very limited spaces
with low labour, so hydroponics can play a great
contribution in areas with limitation of soil and
water and for the poorer and landless people. In
India, the hydroponic industry is expected to grow
exponentially in near future. To encourage
commercial hydroponic farm, it is important to
develop low cost hydroponic technologies that
reduce dependence on human labour and lower
overall startup and operational costs.
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... Their therapeutic potential in fields like immunological regulation, cancer treatment, and cardiovascular health has been highlighted by recent study [31]. Support for the Immune System: According to research by [49], polysaccharides present in mushrooms, like as beta-glucans, have been demonstrated to improve the immune system's performance as well as it prevents the action of free radicals in body resulting in delay of aging process [41]. Effects on Cancer: Studies has shown that specific mushroom chemicals have cancerpreventive characteristics, making certain mushroom extracts having potential as cancer treatment adjuncts [33]. ...
... Mushrooms require high maintain humidity by either placing the kit in a plastic bag or using a humidity tent. Mist the inside of the bag or tent regularly to keep the environment humid Depending on the mushroom variety and growing conditions we should start to see small mushroom pins forming within a few weeks [41]. As they grow, they will mature into full sized mushrooms. ...
... It is a very successful and efficient method of growing plants because it uses 95% less water than conventional farming techniques and takes up less space that even the most advanced hydroponic system [16] and minerals, which may contribute to the plants' increased health and nutritional value. The biomass of the suspended aeroponic plants is accelerated because they receive all of the oxygen that is accessible and carbondioxideThe increased metabolic yield of aerial components from the aeroponic treatment suggested that other crop types should also be taken into consideration for this production strategy, not just root crops [41] The best possible oxygenation is given to mushroom mycelium through aeroponic systems, which promotes growth. Healthier Mushrooms: The absence of soil reduces the likelihood of soilborne diseases, resulting in a lower risk of disease. ...
With the introduction of hydroponics, a cutting-edge technique that is completely changing conventional procedures, the long-standing practice of mushroom growing has changed to suit modern difficulties. Traditionally cultivated in natural substrates, mushrooms are currently flourishing in hydroponic systems, which substitute nutrient-rich water solutions for soil. This change brings about an evolution in the mushroom industry and satisfies the growing need for sustainable agriculture methods. The advantages of hydroponic mushroom culture are unmatched; they include better nutrient control, year-round output, space efficiency, and pest and disease control. Growers can customize fertilizer levels and create ideal growing conditions for a variety of mushroom species thanks to the accuracy of hydroponic systems. Hydroponics overcomes seasonal limitations to guarantee steady mushroom production, satisfying the rising need for fresh produce that is acquired locally. Its layout maximizes available space, which is especially beneficial for urban farming. usage of land. Because hydroponics is an environmentally benign method, there is less chance of soil-borne illnesses and pests, which means less need for chemical treatments. This method creates a regulated, pollution-free atmosphere that promotes improved mushroom quality and consistency. In addition, hydroponic mushroom farming reduces nutrient leakage and uses less water, which is in line with the global trend toward ecologically friendly farming methods. To sum up, the application of hydroponics to the growth of mushrooms represents a revolutionary advancement in mycology. Improved sustainability, production, and profit for mushroom growers are among the benefits that follow. Hydroponics is a viable solution that could revolutionize the mushroom business and make a substantial contribution towards achieving greater sustainability in agriculture as demand for mushrooms develops.
... The hydroponics method might possibly benefit the Trans-Himalayan range in the future. (Sharma et al. 2018, Acharya et al. 2021and Kumar et al. 2022). (Sharma et al. 2018). ...
... (Sharma et al. 2018, Acharya et al. 2021and Kumar et al. 2022). (Sharma et al. 2018). ...
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For many decades, food security has been a worldwide concern. The present research aimed to examine an efficient technique for planting system i.e. hydroponic (a soil less system of farming) and statistical experimental design approach was used to compare the growth of different Leafy Vegetables (Spinach and Lettuce Varieties) in the Cold Desert Region of Trans Himalaya under the designed hydroponic system. The results showed that the leafy vegetable variety that were grown in the NFT system, exhibited significant differences in above attributes. The BC ratio of nutrient solution was found to be four times higher.
... This innovative approach offers a solution to the above issues by allowing for the cultivation of plants in a controlled, soil-less environment. Hydroponics is a way to grow plants using special nutrient-rich water, sometimes with things like gravel or coconut fibre to support them, but sometimes just the water alone [2]. Hydroponics involves growing plants without soil, where their roots are submerged in a nutrient solution [3]. ...
... Reduced EC values often signify insufficient nutrient supply to the crop, leading to nutrient deficiencies and a decline in yield [29]. Therefore, effective EC management in hydroponic techniques can serve as a valuable tool for enhancing both the yield and quality of vegetables [2]. ...
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As our world has become more populated and cities have grown, the amount of land available for farming per person has gone down a lot. Back in 1960, when there were 3 billion people, each person had about half a hectare of land for farming. But now, with 6 billion people, it's down to just a quarter of a hectare, and it's expected to shrink even more to just a tiny 0.16 hectares by 2050. Several things are making this problem worse. Cities and industries are expanding, and climate change is causing icebergs to melt, which can flood and ruin farmland. Also, the soil that we grow crops in has reached a point where it can't get much more fertile, even if we use more and more fertilizers. Some areas have really poor soil, and the natural process of soil getting better with time is getting disrupted because we keep farming the same land over and over. On top of that, there are more droughts, unpredictable weather, higher temperatures, pollution in rivers, and wasteful water use. All these challenges are making it harder to grow enough food using traditional farming with soil. That's why soil-less farming, where plants grow without soil, is becoming more important. It's a way to produce food that uses less space and water, and it's showing some good results around the world. Review Article Thakur et al.; Int.
... The optimal EC values for the tomato flowering to harvest phase is within the range of 1400 µS/cm to 4000 µS/cm in the hydroponic system [70][71][72]. Some studies have found that EC value of 3000 µS/cm is the threshold for all growth stages of hydroponically grown tomatoes [23,73]. ...
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Smart farming using technology-monitored controlled environment agriculture (CEA) has recently evolved to optimize crop growth while minimizing land use and environmental impacts, especially for climate-threatened regions. This study focuses on characterizing crop production using system dynamics (SD) modeling, which is a relatively new approach in CEA settings. Using tomatoes in a hydroponic growing system, we explore an alternative food resource potentially accessible to underserved areas in rural and/or urban settings under abrupt climate variability. The designed autonomous indoor farming platforms (AIFP) are equipped with the Internet of Things (IoT) to monitor the physiological parameters, including electrical conductivity (EC), pH, and water temperature (WT) associated with plant growth. Two varieties of tomato (Solanum lycopersicum) plants were used in this study with two different nutrient inputs (N-P-K ratios of 2-1-6 and 5-5-5) to assess the nutrient application impact on yield, especially focusing on the early stages of tomato to conceptualize and parametrize SD modes. Repeated measure analysis was conducted to investigate the effects of the environmental factors (EC, pH, and WT) in response to changing plant nutrients. The results show that different nutrient compositions (N-P-K ratios) have a noticeable effect on both pH and WT (p < 0.001) as opposed to EC. The study indicates that the proposed AIFP would be a promising solution to produce other crops for indoor farming in a changing climate. We anticipate that the proposed AIFP along with SD tools will be widely adopted to promote indoor farming in changing climates, ultimately contributing to community resilience against food insecurity in disadvantaged areas for years to come.
... We refer the reader to [8][9][10][11][12] for a comprehensive description of these techniques. Hydroponic methods use, on average, 10% of the water utilized in traditional farming [13] as nutrients are delivered directly to the plant roots, minimizing water lost to evaporation. This mode of growing plants can be easily automated and, combined with the fact that the lack of soil protects against pests, these systems make it easier to cater to the unique physiological needs of the plants while eliminating the need for pesticides and other chemicals. ...
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In the face of a changing climate and a rising number of “food deserts" in both rural and urban areas, there is a demand to supply fresh produce year-round to communities at the end of the traditional agriculture supply chain. Vertical indoor farming is a promising mode of next-generation agriculture that boasts reduced water and pesticide usage, improved yields, more consistent quality, year-round cultivation, and cheaper transportation and harvesting costs. Indoor farms can rival industrial greenhouses in size, but small-scale “pod farms" can be deployed to smaller communities and areas where large swaths of land are either unavailable or too costly. These pods are often the size of shipping containers with their temperature, humidity, and plant nutrient supply carefully controlled. Plants inside the pods are grown hydroponically with light supplied by panels of LEDs and, thus, this mode of farming is fundamentally different from greenhouse farming. Many indoor farming pods have recently become commercially available claiming high energy efficiency, but little analysis and optimization work has been done to prove these claims. To drive innovation in the design of these physical systems, we have developed a digital-twin and genomic optimization framework for the optical design of vertical indoor farming pods. We model a completely enclosed indoor farming pod with plants in the three mutually-orthogonal planes and illuminated by LED “walls." We employ ray-tracing methods and a genetic algorithm to determine the LED source tube area size, beam aperture spread, and power requirements for maximal power absorption by the plants.
... The latter was followed in an automatic way thanks to Arduino and raspberry pi 3 boards. The correspondence between the evaluation systems is thanks to 4G LTE (module) (Sharma et al., 2018). The control system is equipped with a component for temperature detection, a component for pH and E. C. detection and various sensors. ...
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All horticultural regions of the world have fundamentally developed in the programmatic era through farmer impact and imaginative development practices. The methods described are used to monitor satisfaction and crop yields. Because of the quality of the soil and the nourishment of the land, their cultivation has improved and created more money. The disadvantage is that it took them a long speculation to acquire the crops, and the level of nutrition was not usually put at its obvious level. In addition, many areas were devoted to production, which required a lot of work to treat the whole area. In order to control the time and methods well, the majority of the regions switched to careful development principles with IoT structures. Growing on water is the most progressive strategy to grow natural plants, vegetables and fruits without using land. The use of Rockwool in agricultural strategies where water contamination is possible for a certain period will result in huge yields and the requirement of longer growing times will be waived. Most of the countries that have practiced smart and economic development with little external intervention. IoT sensors are used in the water cultivation development system to test the situation and quality of yields continuously. They will effectively provide information to the whole system when the water or nutrient level has dropped. In the beginning, the development of hydroponics was done horizontally in small spaces in order to maintain the water flow. Today, it is applied on a vertical structure to save space and water flows when needed. With this method, yields are likely to be achieved even more space-efficiently and with little external intervention. Vertical hydroponics performs better than previous conventional approaches; perhaps the farmers in the extension unit have considered the cost of the total layout. This evaluation paper describes the use of procedures and development of automated methods using IoT platforms. Many reference materials can be used big data. hydroponic system; IoT; sensors; raspberry pi controller; wireless connectivity
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Soilless cultivation commonly referred to as hydroponics or soilless farming, is a groundbreaking agricultural approach that is reshaping the way we cultivate crops. This abstract sheds light on the contemporary methods used in soilless cultivation, their progress, and their versatile applications in agriculture, horticulture and sustainable food production. While traditional agriculture has relied on soil as the primary growth medium, soilless techniques are gaining prominence for their ability to maximize resource utilization, amplify crop yields, address environmental concerns and facilitate year-round cultivation. Hydroponic systems entail cultivating plants in nutrient-enriched water solutions, granting precise control over nutrient levels and water availability. Various techniques like the Nutrient Film Technique (NFT), Deep Water Culture (DWC) and aeroponics have emerged to optimize nutrient distribution, oxygenation and root support. Soilless cultivation often involves using inert substrates like coco coir, perlite or rock wool to provide physical support for plants while nutrient solutions are delivered directly to the roots. This technique balances root aeration, water retention, and nutrient access. Soilless cultivation across diverse crops, including leafy greens, herbs, berries and even larger plants like tomatoes, lettuce and cucumbers. Furthermore, it emphasizes the potential of soilless techniques in addressing food security challenges, enabling cultivation in arid regions and reducing the ecological footprint of agriculture.
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The objective of this research is to investigate the effect of the introduction of hydroponic barley; produced as feed supplement in the ration, on the performance of feedlot calves. This study was performed in the Taroudant region (South of Morocco), during a trial period between July and October 2017). A total of 100 calves were used in a feeding trial, which were divided into two groups. The calves of the first group received a total mixed ration (control), while the calves of the second group received a similar ration with the addition of hydroponic barley.Similar growth performance is observed for the two groups, which is easily explained by the equivalent rationing. In the finishing phase, however, a higher average daily gain is observed for the group fed with an enriched diet in hydroponic green fodder. In fact, the average daily gain for this group amounts to 1.48 Kg/Day compared to 1.42 Kg/Day for the control group.The slaughter results confirm those noted in terms of growth performance, with a relatively similar carcass yield for the two groups.However, since hydroponic fodder reveals a positive impact especially at the level of the finishing phase, it seems judicious to introduce it in the key phases of fattening and finishing in order to perfect the weight gain of the species benefiting from this contribution.The test results suggest that hydroponic barley based rationing is to deepen, and that it would be desirable to repeat the experiment by testing different levels of hydroponic barley intake, adjusting both the type and the level of complementation, with a more accurate monitoring of feeding.
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Technological advancement in recent decades has allowed for crop cultivation in soilless controlled environments, known as hydroponics, and this is being employed in an increasing number of factories worldwide. With continued local and regional disruptions in the supply chain to provide mineral fertilizers, new pathways to generate nutrient solutions are being developed. One potential approach is the recovery of nutrients from organic waste and wastewater using bioponics. Bioponics refers to the biological mineralization of organic residues through processes such as anaerobic and aerobic digestion and the use of such organically produced nutrient solutions in hydroponic systems. However, without disinfection of the nutrient solution, the high microbial loads increase the risk of pathogens affecting plant and consumer health. In this work, electrochemical hydrogen peroxide (H2O2) demonstrated success in reducing microbial loads. Different scenarios of application were considered: (1) variation in the H2O2 concentration in the nutrient solution by dosing H2O2 from ex situ electrochemical production, (2) variation in the dosing time-dependent reaction between the nutrient solution and H2O2 produced ex situ, and (3) the in situ production of H2O2 of the organic nutrient solution. The highest tested H2O2 concentration of 200 mg L−1 showed a microbial load reduction of bacteria at 93.3% and of fungi at 81.2%. However, the in situ production showed the highest reduction rate for bacteria and fungi in bioponic nutrient solutions, where longer reaction times also impact microbial concentrations in situ. Final microbial reductions of 97.8% for bacteria and of 99.1% for fungi were determined after a H2O2 production time of 60 min. Overall, our results show that electrochemical H2O2 production can be used to disinfect bioponic nutrient solutions, and the production cell can be implemented in bioponic systems in situ.
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Comparison between aquaponics, hydroponics and traditional method for cultivation of spinach was carried out. In this study, spinach was grown in the soilless media like perlite and sphagnum moss. Media were used to support plant growth. From these Media the perlite media was used in aquaponics and sphagnum moss was used in hydroponics. This study was carried out to examine different morphological characters like height, germination period, surface area, the yield of spinach, and biochemical analysis like protein, carbohydrate, chlorophyll content. The height and surface area of the traditionally cultivated spinach (Height- 23 cm) (Surface area- 79 was more than the hydroponically (Height- 18 cm) (Surface area- 70 and aquaponically (Height- 20.5) (Surface area- 72 cultivated spinach. But the germination period of aquaponically and hydroponically cultivated spinach (4th day) was earlier than traditionally cultivated spinach (5th day). The protein and carbohydrate content was more in aquaponically (Protein – 2.9%), (Carbohydrate – 3.9) and hydroponically (Protein - 2.7%), (Carbohydrate – 3.8) cultivated spinach than traditionally (Protein– 2.6%), (Carbohydrate– 3.8) cultivated spinach. Chlorophyll content was highest (0.07%) in the traditionally grown spinach and (0.06%) in aquaponically as well as hydroponically grown spinach. In traditionally and hydroponically cultivated spinach, plants were provided with all the nutritional requirements externally but in aquaponics nutrients were provided naturally through fish excrete. In hydroponics nutrient requirement was less compared to the traditional method. In this work, guppy fishes were used in aquaponics as a source of nutrients. For hydroponics, the N: P: K fertilizer named 19:19:19 was given in small quantities. For traditionally cultivated spinach the fertilizers like Urea, 19:19:19 and 15:15:15 were applied. The yield of the aquaponically cultivated spinach was measured (4455Kg/acre); it was slightly more than hydroponically cultivated spinach (3780 Kg/acre) and much more than the traditionally cultivated spinach (1615 Kg/acre).
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Salt added to nutrient solution is an easy method that can improve tomato fruit quality, but plant growth and fruit production are negatively affected. Salinity reduces tomato root elongation rate and lateral root growth due to restriction of root cell growth and increased root lesion. Tomato leaf, shoot height and stem diameter reduced under salinity stress caused by photosynthesis reduction, tissues expansion reduction and cell divided inhibition. Salinity also reduces leaf chlorophyll content, stomatal resistance and photosynthetic activities. Total yield of tomato is significantly reduced at salinity equal and above 5 dS m<sup>-1</sup>, and a 7.2% yield reduction per unit increase in salinity. Salinity can decrease root water uptake through its osmotic effect, and subsequently induce water stress. Fruit quality is the only parameter which is positively affected with increased salinity.
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Microgreens are gaining interest for claimed high nutraceutical properties, but data on their chemical composition are so far limited. Although often grown hydroponically, their mineral requirements are still unknown. This study aimed to provide an insight into yield, mineral uptake, and quality of basil, Swiss chard, and rocket microgreens grown in a hydroponic system. With reference to data reported in literature for the same species hydroponically grown but harvested at adult stage, these microgreens yielded about half, with lower dry matter percentage, but higher shoot/root ratio. They showed high concentrations of some minerals, but their nutrient uptake was limited due to low yield. Nitrates content was lower if compared with that usually measured in baby leaf or adult vegetables of the same species, as well as the concentration of chlorophylls, carotenoids, phenols, and sugars. Therefore, microgreens seem to be interesting and innovative low-nitrate-salad crops requiring low fertiliser inputs. Nevertheless, an improvement in yield as well as in the content of nutraceutical compounds would be desirable.
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Aquaponics (AP) is a food production system that combines hydroponic (HP) crop production with recirculating aquaculture. Different types of hydroponic systems have been used for growing crops in aquaponics. However, very few studies have compared their suitability and efficiency in an aquaponic context. The study presented here compares tomato yield, morphological (external) and biochemical (internal) fruit quality, and overall tomato plant vitality from three different HP systems (nutrient film technique, drip irrigation system, and floating raft culture) and examines the distribution of nutrients in different parts of the tomato plant. Three replicate AP systems were set up, each incorporating the three different HP systems coupled with a separate recirculating aquaculture unit growing Nile tilapia. The results showed that the choice of the cultivation system had little influence on most of the above-mentioned properties. Tomato fruit mineral content was found to be in similar range for N, P, K, Ca, Mg, Fe, and Zn as reported in the literature. Yield and fruit quality were similar in all three systems. However, the drip irrigation system did perform slightly better. The slightly higher oxygen radical absorbance capacity (ORAC) of the fruits grown in AP in comparison to commercially produced and supermarket derived tomatoes might indicate a potential for producing fruits with higher health value for humans.
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Vertical farming systems (VFS) have been proposed as an engineering solution to increase productivity per unit area of cultivated land by extending crop production into the vertical dimension. To test whether this approach presents a viable alternative to horizontal crop production systems, a VFS (where plants were grown in upright cylindrical columns) was compared against a conventional horizontal hydroponic system (HHS) using lettuce (Lactuca sativa L. cv. “Little Gem”) as a model crop. Both systems had similar root zone volume and planting density. Half‐strength Hoagland's solution was applied to plants grown in perlite in an indoor controlled environment room, with metal halide lamps providing artificial lighting. Light distribution (photosynthetic photon flux density, PPFD) and yield (shoot fresh weight) within each system were assessed. Although PPFD and shoot fresh weight decreased significantly in the VFS from top to base, the VFS produced more crop per unit of growing floor area when compared with the HHS. Our results clearly demonstrate that VFS presents an attractive alternative to horizontal hydroponic growth systems and suggest that further increases in yield could be achieved by incorporating artificial lighting in the VFS.
It is critical to identify effective buffer chemicals which are capable of regulating the pH of nutrient solution to a desirable level for best hydroponic production of crops. Greenhouse experiments were conducted to examine the pH dynamics of nutrient solutions amended with different inorganic acids during hydroponic production and the yield and nutritional quality of the resulting crops. A typical nutrient solution (pH 8.2) was adjusted to a pH of 5.6±0.2 with 1 M HNO3, 1 M H3PO4, 1 M H2SO4, and a 3:1:1 (v/v/v) mixture of all three acids, respectively. Water spinach (Ipomoea aquatica Forsk) was hydroponically grown for 25 d in the unadjusted control and the pH-adjusted nutrient solutions. The different treatments were monitored for pH changes of the nutrient solution, and measured for shoot yield and nutritional quality of the grown water spinach. It showed that the solution pH adjustments introduced additional anions but did not significantly increase the electrical conductivity (EC). The HNO3-H3PO4-H2SO4 mixture was able to achieve an optimal solution pH ranging from 5.5 to 6.5, while any of the acids only failed to maintain the solution pH within optimal range for 48 h after each adjustment. The shoot fresh weight, dry weight, and height of water spinach grown in the mixed acids-treated solution were the greatest among the five treatments. Relative to the control, the acid mixture treatment also increased the vitamin C, soluble sugar and crude protein contents in plants. Thus, the mixed 3:1:1 (v/v/v) HNO3-H3PO4-H2SO4 is recommended for regulating the pH of nutrient solution in hydroponic production of leafy greens.
A hydroponics system developed using a nutrient film technique was used to evaluate the effectiveness of rice husk biochar (RB) alone or in combination with perlite (PL) as substrates for increasing the growth of leafy vegetables compared with that of PL. Seedlings of cabbage, dill, mallow, red lettuce, and tatsoi were grown hydroponically in PL, RB, and PL + RB (1:1 ratio of PL to RB, v/v) substrates for a 30-d under optimal environmental conditions in a greenhouse. Shoot length and fresh/dry masses of cabbage, dill, and red lettuce plants grown in RB substrate were decreased by 49% on average compared to those plants grown in PL substrate. In contrast, PL + RB substrate led to approximately 2-fold increases in shoot length, number of leaves, and fresh/dry masses of leafy vegetable plants compared with those grown in PL substrate. Foliar nutritional composition (Ca, Mg, K, Na, Mn, Fe, and Zn) and nitrogen status (SPAD index) of plants grown in PL + RB and PL substrates suggested the presence of optimal growth conditions for ensuring optimum yield with high quality. In addition, RB substrate contributed to respective increases of 1.2–3.5-fold in leaf K, Mg, Mn, and Zn contents in most vegetable plants compared with those grown in PL substrate. The RB alone or in combination with PL substrates decreased algal growth in the nutrient solutions as confirmed by scanning electron micrographs of microalgae on the RB surface. The results also indicated that use of PL + RB hydroponic substrate could be an alternative and effective technology for the better management of unwanted algal growth in nutrient solutions and high production of leafy vegetables.
The production and quality of red bell pepper (Capsicum annuum L. cv. 'HA3378') fruits were evaluated in a hydroponic system in a passive-ventilated greenhouse during spring and summer 2000 in Gainesville, FL, USA. Two plant growing systems were used: a) "V" trellis system (plants pruned to two stems, individually and vertically trained); and b) "Spanish" system (plants not pruned, with lateral horizontal strings for vertical canopy support). Plants were grown in flat bags or in polyethylene pots, both filled with perlite. Plant population densities were 1.5, 1.9, 3.0, and 3.8 plants per m2. Marketable fruit yields were similar with both growing systems although production of extra-large fruit grade was greater with non-pruned than with pruned plants. Marketable fruit yield per m2 increased linearly with plant density from 3.5 kg·m-2 (1.5 plant/m2) to 7.4 kg·m-2 (3.8 plant/m2). Plants grown in bags and pots produced similar marketable yields. Non-pruned plants had a lower percentage of fruits with blossom-end rot than pruned plants (32 vs. 62%). Non-pruned plants grew to 105 nodes that supported flower buds while pruned plants grew only to 59 nodes. The total fruit that set was lower in nonpruned plants than in pruned plants (34 vs. 50% of the total number of flowers). Fruit set per plant decreased linearly as plant density increased. The "Spanish" trellis system with a density of 3.8 plant/m2 required less labor (25% of the labor needed for the "V" system) and resulted in greater yields of extra-large fruits than with the "V" system during a spring production season in a passive ventilated greenhouse.