2. What is microbes?
Microbes, or microorganisms
are minute living things that
are usually unable to be
viewed with the naked eye.
Bacteria, fungi, protozoa, algae,
viruses are examples!
3. Chemical in Agriculture
Farmers use -
Chemical Pesticides.
Chemical fertilizers.
In the last century, chemical fertilizers were used in
agriculture. Farmers were happy of getting increased
yield in agriculture in the beginning .
But slowly chemical fertilizers started displaying their
ill-effects such as:
Polluting water.
Destroying micro-organisms
and friendly insects
Making the crop more
able to the attack of diseases.
4. Microbes in Agriculture
Microbes are harmful but some
microbes are useful for our day to life.
Microbes in agriculture used as-
Bio-control agent.
Biological fertilizer/ Biofertilizer.
5. Biological control agents
First coined by Harry Smith
in relation to the biological
control of insects.
Biological control agents are
◦ Pollution free.
◦ Host specific.
◦ Expensive.
9. Pseudomonas
Xanthomonas
Use as Herbicides.
Suspension of such bacterial spores on
the plant.
Not harmful for major crops.
Weeds to be controlled.
Ex- P. Protegens
Weed killed with herbicides
10. Beauveria
Use spore sprayed on affected crops .
Can be used as a biological insecticide to
control a number of pests such as aphid,
mites ,mealy bugs, whiteflies, and many
other insects.
Ex- Beauveria bassiana
12. Trichoderma
Very important and famous for soil bone
plant pathogen.
Generally grows in its natural habitat on
the root surface and so affects root
disease in particular.
Can also be effective against foliar
diseases
Ex-T. harzianum, T. hamatum
14. Nosema
It is available in powder from
It is poisonous.
Grasshoppers, Caterpillars, Crickets eat
the tender part of plants.
They die because of nosema.
15. NPV(Nuclear Polyhedrosis
Virus)
It is also available in powder from
Unable to affect humans in the way it affects
insects
It is transferred from insect to insect through
crystals in all of their bodily emissions.
Kill Gypsy moths, Caterpillars.
16. Biological fertilizer/
Biofertilizer
Pest can control by bio-control agents but what
about the fertility of soil.
When palnt production or crops production is not
enough chemical fertilizer can switch over
biofertilizer.
It is nothing but either bacteria or blue green algae
or some fungus.
These microorganism should be-
I. Fixers.
II. Phosphate solubilizers.
N2
18. Free-living
Fixing bacteria
• It is available in powder from
• Convert atmosphere nitrogen into nitrate
and nitrite.
• Increase the nitrogen contain of soil.
Azotobacter
Clostridium
Bacillus polymyxa
N2
19. Free-living
Fixing BGA
Make special cells called heterocysts.
Heterocysts are cells that are terminally
specialized for nitrogen fixation.
Use only paddy fields.
By dead Nitrate and ammonia will be
available.
Nostoc, Anabaena, Aulosira
N2
20. Symbiotic
Fixing Bacteria
It is well known biofertilizer.
Always associated with roots of legumes
plants.
Take nitrogen from the air into Ammonia
which acts as a natural fertilizer for the
plants.
Need higher amount of nitrogen
Rhizobium-Root nodules in
legumes
N2
21. Symbiotic
Fixing BGA
•Make special cells called heterocysts.
Heterocysts are cells that are
terminally specialized for nitrogen
fixation.
Use only paddy fields.
Anabaena Azollae in Azolla.
N2
22. Mycorrhiza
Mycorrhizas are commonly divided into
ectomycorrhizas (external surface of root)
and endomycorrhizas (inside the cell).
They can absorb more amount of calcium,
magnesium, Water and most important
phosphate.
24. EFFECTIVE
MICROORGANISM
Complex microorganism solution.
It contains mainly 3 species such as
Lactic acid bacteria, Yeast, Phototrophic
Bacteria.
Collected from food industries and nature
25. EM IN AGRICULTURE
Enhances the photosynthetic capacity of
crops
Develops resistance of plants to pests
and disease
Improves physical, chemical and
biological environments of the soil and
destroy soil born pathogens and pests
26. Microbes in Agriculture
Bio-control agent are expensive ,safe then
chemical pesticides.
Biofertilizers are cheap ,safe and
renewable resources rather than chemical
fertilizers.
At last microorganisms play an important
role in Agriculture.