2. By
Shehzad Ahmad Kang
Ph.D - Plant Breeding & Genetics
Corresponding email ID:
shehzadpbg@gmail.com

4.  Hydroponics, the ‘water culture’ of plants, has been
used in both research and commercial contexts since
the 18th century.
 plants needs only less dose of inorganic elements e.g.
water, oxygen and sunlight, to grow.
• It was later realized that plants can grew better
hydroponically if the solutions would be aerated.

5.  It permit to easily observe the effects of elemental
deficiencies and toxicities and to study other aspects of
plant development under more controlled conditions
i.e. temperature, control light and specific dose of
nutrients for experiments.

6. The growing of plants in a solution of nutrients necessary
for plant growth, rather than directly in soil.

7. What is needed for a plant to survive?
 Water
 Sunlight
 Air
 Nutrients
 Anchorage

8.  Salt Tolerant Experiments.
 To produce disease free crops like wheat, Barely,
lettuce, tomato and others etc.
 To grow transgenic plants for screening after genetic
transformation.

12.  Passive systems (no moving parts) are great for
beginning hydroponics gardeners because they are
inexpensive, portable, and simple to set up.
 Active systems employ pumps and other devices to
deliver nutrient solutions to plant roots.

13.  The capillary or wick system do not use pumps or
timers. Water and nutrients are drawn up to the roots
by capillary action. These systems may be important
when designing a system to operate in a space station
where gravity is nonexistent.

14.  Most versatile. Each time the water floods from the
lower reservoir into the upper growing tray, the roots
are bathed in the fresh nutrients. When the nutrient
drains back to the reservoir, fresh air is drawn through
the root system refreshing oxygen to the roots.

15.  The NFT systems provide a constant film of water and
nutrients along the bottom of a channel. In effect, part
of the roots grow down in the water/ nutrients and parts
of the roots above the water line getting fresh air and
oxygen

17.  Salinity stress is a limitation to the productivity of
agricultural crops worldwide.
 It has been estimated that almost 80 million hectares of
arable lands worldwide is currently affected by salinity.
 This issue showed big losses in crop yield and this
problem can minimize by the development of salt
tolerant varieties of crops for
• good seed germination
• Plant vegetative and reproduction growth
• And plant biomass and grain yield

18.  The soil solution of saline soil is composed of a range
of dissolved salts i.e. NaCl, Na2SO4, MgSO4, CaSO4,
MgCl2, KCl and Na2CO3, each of which contribute to
salinity stress whereas NaCl is the most prevalent salt
and has been the focus of much of the work on salinity
to date.
 Because high concentrations of NaCl in soils may
ultimately help to improve yield on saline lands.
 Salinity tolerance is a difficult trait to score in the field
and is often genetically complex.
 Hence, identification of salinity tolerance loci/genes
and their selection using molecular markers is needed
to assist in the breeding of salt-tolerant crops like
SSR,RAPD,RFLP,AFLP etc.

19.  Quantitative trait loci (QTL) have been identified for
germination, plant growth and reproduction process
and other various growth parameters measured in saline
hydroponic culture i.e. wheat, Barely etc.
 Results of a study by Gorham et al. (1990) also
suggested that barley chromosomes 6H and 7H could
enhance Na+ exclusion or K+/Na+ ratios in a wheat
background.
 Hexaploid wheat genome (AABBDD) accumulates less
Na+ in the shoot relative to K+ and this trait has been
attributed mainly to the Kna1 gene on chromosome 4D.

20.  Good seed germination.
 Plant height.
 Plant biomass/grain yield.
 Long root length.
 Good vegetative and reproduction growth.
 High shoot length/weight.

21. 1- Conventional breeding approaches
o Introduction of germplasms.
o Screening of line for salt tolerance.
o Selection of genotypes for salt tolerance.
o Hybridization with desire genotype.
• Evaluation of salt tolerant lines through screening and
then hybridize with high yielded line to incorporate salt
tolerant genes by back crossing method.
• This technique is very time consuming and costly and
breeders in modern globe now approach the
Biotechnological breeding approaches salt tolerant
breeding.

22.  Conventional breeding strategy for salt tolerance is not
much successful due to reproductive barrier,
transformation of other undesirable traits. So to avoid
this problem, biotechnological strategy is more
preferred, as it only deals with the specific gene(s)
transferred i.e.
 Molecular markers (SSR,RAPD,RFLP,AFLP etc.)
Used to identify the desirable gene.
 Recombinant DNA method for gene transformation
 Tissue culture- Technique used to growth the transgenic
plant material.

23.  Growing in Any Condition and Season-
Systems may be constructed and used in any location
from space to under water exploration.
 Smaller Growing Area
 More control of the growing environment of plant
 Year-round supply

24.  Faster Growth-
Hydroponics works by automatically getting the
complete nutrient mixture and water to the roots
without drowning the plant. Plants get everything
they need all the time, so they do not waste growing
a lot of roots or searching for nutrients.

25.  No Weeds or Pests-
Gardening without soil eliminates the weeds do you do
not need weed sprays. Also, because there are no
weeds, there will be no backache from a hoe or
rototiller. Since most pests live and breed in the soil,
you do not need to use pesticides or other toxic
chemicals.

26.  Great Plant Quality and Taste-
Since the plants get everything it needs, all the time, it
will reward you with great taste, strong and fast
growth, and overall plant quality.

27.  Cost of initial investment on hydroponic systems is high.
 Hydroponic production is management, capital and labor
intensive.
 A high level of expertise is required.
 Daily attention is necessary.

28.  Specially formulated, soluble nutrients must always be
used.
 Pests and diseases remain a big risk.
 Some water born diseases can spread rapidly in
recirculation system.