This document discusses bacteria and their importance in agriculture. It describes how certain bacteria can fix nitrogen from the air, making it available to plants as nutrients. These nitrogen-fixing bacteria include Rhizobia, which form nodules on the roots of legumes, and Azotobacter. The document also explains how Bacillus thurigiensis is used as a biological pesticide by producing insecticidal proteins during sporulation. Some common biofertilizers containing nitrogen-fixing bacteria that are used to enrich soil fertility are also named, such as Nitragin for legumes and Azotobakterin for many crop types.

1. In the name of Allah the most
beneficent and the most merciful

2. BACTERIA
Introduction and importance

3. Bacteria
• Bacteria are the unicellular organisms.
• They are of great importance in the
biotechnology industries like
I. Agriculture
II. Dairy
III. Environment etc.

4. Importance of Bacteria
• There are certain bacteria which contain
special properties which are beneficent for
plants
• These are present in soil and affect the crops
by fighting against the harmful bacteria and
are also the source of providing nutrition to
plants.

5. Importance of Bacteria
• Bacteria is useful in agriculture by following
two methods.
• As they act as :
I. Nitrogen fixer
II. As Pesticides

6. NITROGEN FIXATION
overview

7. As Nitrogen fixer
• Bio-fertilizers fix atmospheric nitrogen in the
soil and root nodules of legume crops and
make it available to the plant.
• Which is then used by the plants through root
hairs and consume for many purposes like:
– Growth
– Photosynthesis
– And in many other processes

8. Nitrogen Fixation
• Importance
• All life requires
compounds e.g. proteins
and nucleic acids
• Air which is 79%
nitrogen gas is the major
reservoir of nitrogen.
• But most organisms
cannot use nitrogen in
this form.
• Plants secure their nitrogen in
fixed form i.e. incorporated in
compounds such as:
• Nitrate ions
• Ammonium ions
• Urea

9. EXAMPLES OF BACTERIA USE IN
AGRICULTURE

10. Azoarcus
Nitrogen fixing bacteria & seed
germinator

11. Rhizobia
Nitrogen fixing bacteria
Rhizobia nodules on Vigna
unguiculata

12. Bacillus thurigiensis
Pesticide in action

13. BRIEF DESCRIPTION TO BACTERIA
USE IN AGRICULTURE

14. Azoarcus
• Introduction:
– It is a nitrogen fixing bacteria and also helps in
seed germinator
• Working in seed germination:
– When the seed is sown in the soil, it grows in the
seed and environment of mutualism creates.
• Bacteria increases the fertility of soil and provide such
nutrients to the soil which are useful for plant growth.
– They also help in softening of food in seed and so
plant grows out of the seed

15. Rhizobia
• Introduction:
– Gram-negative, motile, non-sporulating rods
– A soil bacteria that fix nitrogen after becoming
establish in inside the root nodules of legumes
e.g. Fabacae.
– Rhizobia requires a plant host, they cannot fix
nitrogen independently.

16. Rhizobia
• Importance:
– Although much of the nitrogen is removed when
protein rich grain or hay is harvested especially
when nitrogen fertilizer is not used.
– Nitrogen is the most commonly deficient nutrient
in many soils around the world and it is the most
commonly supplied plant nutrient.
– Supply of nitrogen through fertilizers has severe
environmental concerns.

17. Bacillus thurigiensis
• Introduction:
– Bacillus thurigiensis or BT is a gram-positive soil
dwelling bacterium.
– Commonly used as a biological pesticide.
– Habitat:
• In the gut of caterpillars of various types
– Moths and butterflies
• On leaf surfaces
• Aquatic environment
• Animal feces
• Flour mills
• Grain storage facilities

18. Bacillus thurigiensis
• Mode of action:
– During sporulation many BT strains produce
crystal proteins (proteinaceous inclusions) called
sigma-endotoxins that have insecticidal action.
This has led to their use as insecticides.
– More recently to genetically modified crops using
BT genes

19. Bacillus thurigiensis
• Importance
– Spores and crystalline insecticidal proteins produced by
B.thurigiensis have been used to control insects/pests.
– Since 1920s and are often applied as liquid sprays.
– They are now used as specific insecticide under trade
names such as:
• Dipel
• Thuricide
– Because of their specificity, these pesticides are regarded
as environmentally friendly with little or no effect on:
• Humans
• Wildlife
• Pollinators and most other.

20. BIO-FERTILIZERS
Names and little description

21. Fertilizers
• Following are the few Bio-fertilizers:
– Nitragin
• Made from active nodule bacteria.
• Used for leguminous plants .
• They fix the atmospheric nitrogen, which is assimilated by plant.
• It is most effective in combination with other fertilizers.
– Azotobakterin:
• Made from active culture of microorganism
• It grows actively only in fertile soils with many organic substances
– Fosfobaktrin
• White ,light grey or yellow powder
• Bacterial fertilizers are usually applied to the soil together with the
seed or planting material

22. Bio-fertilizers
Nitrogen Fixer Pesticides