This briefly tells about the different seed treatments as well as special seed treatment techniques which is very needy for the better survival of the crops..Hope you will njoy this..
2. Seed treatment refers to the application of fungicide , insecticide
or both to the seeds to disinfect (deep seated ) and disinfest
( over seed coat ) them from seed borne or soil borne pathogenic
organisms and storage insects.
Benefits of seed treatment
1.Prevention of spread of plant diseases both systemic
and non systemic
2.Protects seed from seed rot and seedling blights
3. Improves germination
4. Provides protection from storage insects and pests.
3. Dates back to 17th century when salt water was accidently
discovered to control bunt and stinking smut of wheat seed.
In 1755, M.D Tillet, a french botonist recommented the use of
lye and lime as a chemical treatment for wheat seed
Some 50 years later ,Prevost a Swiss botanist ,discovered the
use of copper fungicides as seed treatment.
New concepts of treating seeds with Organomercurials like
Ceresan and Semesan were introduced in 1920.
10. Hanson et al. [1] divided seed treatment methods into three
groups
MECHANICAL METHODS
PHYSICAL METHODS
CHEMICAL METHODS
OTHER METHODS
11. 1. MECHANICAL METHODS
These are designed to remove infectious materials mixed
with seeds.
Seeds can be mechanically cleaned thoroughly before
seeding to remove pathogenic organisms from the seed
surfaces.
This often requires further treatment.
12. 2. PHYSICAL METHODS
Physical methods include hot-water and water-soak
treatments and ultraviolet, infrared, X-ray and other types of
irradiation.
Do not protect seeds from soilborne organisms
13. 3. CHEMICAL METHODS
Most commonly used method because of its
effectiveness and ease of handling.
IDEAL CHEMICAL would be;
Highly effective in controlling the pathogen
Harmless to the seed,animals and non toxic to people
Economic to use
Easy to apply
Non corrosive to machinery
Stable for long periods
14. A) Mercurial Compounds
1. Organo mercurials: Small grains , flax cotton and
safflower
Eg: PMA (Phenyl Mercuric acetate), MEMC (Methoxy
ethyl Mercury chloride), EMC (Ethyl mercuric chloride )
2.Inorganic mercurials: Mercuric chloride, mercurious
chloride and mercuric oxide
Tuber and root crops , Garden and vegetable crops
Chemicals used for Seed treatment
15. B) Non Mercurials
1.Organic non mercurials
Less effective than the organic mercurials
Less damaging to the seeds
Less damaging to the persons handling the seeds
Over dose is not harmful and viability is not effected
Eg Thiram, Captan, Carbendazim, Metalaxyl
2. Inorganic Non Mercurials:
Copper carbonate, Copper sulphate – Bunt disease in
wheat
Cuprous oxide- seed decay and damping off in
vegetables
16. I. Chemical treatments to improve germination and
vigour potential
Soaking / treating the seeds with nutrients vitamins and
micronutrients etc
1.Paddy: Seeds can be soaked in 1 % KCl solution for 12 hours
to improve the germination and vigour potential.
17. 2.Sorghum: Seeds could be soaked in NaCl2 (1 %) or KH2PO4
(1%) for 12 hours for improving the germination and vigour
potential.
18. 3.Pulses : Seeds can be soaked in ZnSO4, MgSO4
and MnSO4 100 ppm solution for 4 hours to improve
the germination and vigour potential.
19. 4. OTHER METHODS
ABCD specifically controls Fusarium, Alternaria, Drechslera,
Aspergillus flavus
It was also very effective in controlling the major stored grain
pests
ABCD was also found effective in reducing seedborne
diseases
Siddiqui and Agarwal [2] brought to light a
new material for seed treatment, ABCD
(attapulgite - based clay dust), developed
at the Indian Institute of Chemical
Technology (CSIR, Hyderabad) for seed
treatment and safe storage of seeds and
food grains.
20. 1. Seed disinfection: It refers to eradication of
fungal spores present within the seed coat or
more deep seated tissues
2. Seed disinfestations: It refers to the
destruction of surface borne organisms that
contaminated the seed surface but not
infected the seed.
3. Seed protection: To protect the seed and
young seedling from organisms in the soil
which might otherwise cause delay of the
seed before germination.
Seed Treatment Fungicides
22. 1 .Slurry treaters
A slurry is prepared by mixing the
chemical with water.
The treatment material to be
applied as slurry is accurately
measured through a simple
mechanism comprised of a slurry cup
and seed dump pan.
The cup introduces a given amount
of slurry with each dump of seed into
a mixing chamber where the seeds are
mixed thoroughly.
23. 2.Direct treater
Panogen and Mist o matic treater
The "mist-o-matic" treater applies chemical as a mist
directly to the seed.
The treater is equipped with a large treatment tank, a
pump and a return that maintains the level in the small
reservoir from which the seed is fed.
24.
25. A simple mixer can be made
by running a pipe through a
drum at an angle.
The drum is then mounted
onto a stand.
The seed and treatment are
placed in the drum and it is
rotated slowly until all the seeds
are cornered with the chemicals.
3. Drum Mixer
26. Liquid materials can be dripped on the seed as they
enter a grain auger or straw conveyer.
By the time seeds have left the auger the chemical is
spread on the seeds.
4. Grain Auger
5. Shovel
Seeds are spread on a clean dry surface 10-15 cm in depth.
The proper amount of chemical is diluted with water and
sprinkled over the seed.
Mixing is done with shovel or sloop turning the seed at
least 20 times.
27.
28. 1. SEED
COATING
Seed coating is the application of useful
materials to the seed without changing its
general size or shape.
Seed coating has been utilised to ameliorate environmental
stresses such as drought and flooding
Seed coating with peroxide compounds provide oxygen to
seeds under anoxic soil conditions
Hydrophilic polymers maintain a high water potential
around germinating seeds
29. 2. SEED PELLETING
Pelleting is enclosing of seed in a filler material using an
adhesive with bioactive chemicals to ensure singling of seed and
size increases for easy handling.
The binders for pelleting include gum arabic ,gelatin, starch
and the commonly used fillers are Lime stone, gypsum, talc,
vermiculite, peat etc.
The pellet may act as a physical barrier as well as mechanical
barrier.
30. 3. ENCAPSULATION OF SEEDS
Natural seeds also can be
encapsulated using hydrogels
Redenbaugh et al.[3] mixed
propagules with sodium alginate
solutions and then transferred
the coated propagules to a
calcium salt to form a soft
capsule.
This technology was developed to form
capsules of somatic embryos by gelation to
enhance their stability
31. 4. FLUID DRILLING AND SEED PRIMING
It consist of germinating
seeds in aerated water until
radicle emergence
The seeds are then mixed in
a viscous gel and sown with
an appropriate drill.
The gel prevents seeding
injury to the emerging
radicle and maintains seed
moisture
32. Seed priming allows for the regulation of the water content in
the seed, either by soaking the seeds in water or in a solute; or, by
exposing the seeds to water vapor.
Osmoticums such as PEG and inorganic salts have
been used as a priming agents
o Hydropriming
o Osmotic priming.
o Solid matrix priming.
o Drum priming
The seeds imbibe water for a time
interval. After the time interval, the process
is halted right before the first root, called
the radicle, emerges from the seed.
With priming the germination process is
activated so that seeds germinate more
rapidly and emerge more uniformly
33. 5. BIOLOGICAL SEED
TREATMENTS
Seed treatment with beneficial microorganisms like
Rhizobium spp. to treat leguminous seeds for nitrogen
fixation and Azospirillum and other nitrogen –fixing
bacteria has long been known.
Fathey [5] noted that an endophytic bacterium,
Clavibacter xylii, when introduced into corn seeds is
transformed to produce an insecticidal protien (§-endo
toxin) from Bacillus thuringenesis which is active against
the european corn borer
34.
35. As a warning that the seeds
have been treated .
The colour also indicate the
uniformity of the chemical
coverage.
Coloring of seeds prevents
inadvertant use of treated
seeds for food or feed
purpose.
Coloring of seeds
36. Never used for animal or human consumption.
The treated seeds must be properly labelled.
Care must be taken to treat the seeds at correct dosage.
Do not treat the seed with concentrated liquid
products.
The technique must be economical and practical for the
specific crop, and above all the materials used should be
environmentally safe
Precautions for seed treatment!!!
