The document discusses the use of ACC deaminase-containing bacteria and mycorrhizal fungi to help plants tolerate abiotic stress from salt. Case studies show that inoculating tomato and pea plants with these microbes improved plant growth under salt stress compared to non-inoculated plants. The microbes help plants by reducing stress-induced ethylene levels in the plant. A combination of ACC deaminase bacteria, mycorrhizal fungi, and rhizobia was most effective at improving nutrient uptake, photosynthesis, and stress defenses in pea plants. Large-scale application of these microbes could help crops better tolerate salt stress.

2. ACC deaminase : MANAGING
ABIOTIC STRESS IN CROPS
Presented By:
ANIL KUMAR
M.Sc. MICROBIOLOGY 1st Year
IARI NEW DELHI
CREDIT SEMINAR- I
MB-691
SEMINAR LEADER: RAJEEV KAUSHIK
CHAIRPERSON : Dr. K . ANNPURNA

3. stress
Deviation from optimal condition of life
Gene expression
Cellular metabolism
Growth rate
yield

4. STRESS
ABIOTIC
WATER
DEFICIT
EXCESS
TEMPERATURE
HIGH
LOW
SALT/ION
TOXICITY
DIFFICIENCY
AIR
POLLUTION
OTHERS
BIOTIC
4

5. How abiotic stress affects the growth and development of crop
(Vicers et al., 2009)

6. PLANT GROWTH AS FUNCTION OF AGE:
Arrows indicate stress onset which
causes growth to slow or stop
But actual yield varies according to the
number and intensity of the stresses
that a plant experiences.

9. Modified from: XiteBio Technology Inc.
Plant stress control

10. PLANT RESPONSES TO ABIOTIC
STRESS:
• Closing of stomata
• Change in morphology of plants
• Production of phytohormone
(Auxin, ABA, Ethylene)

12. SYNTHESIS OF ETHYLENE
1ST
peak/Be
nefi-cial
peak
2nd
peak/Del
ete-rious
peak
Ethylene

15. • A 1-aminocyclopropane-1-carboxylate deaminase is
an enzyme that catalyzes the chemical reaction
• This enzyme belongs to the family of hydrolases, those
acting on carbon-nitrogen bonds other than peptide bonds

19. ACC (1-Aminocyclopropane-1-carboxylase) deaminase

24. CASE STUDY : 1

25. MATERIALS AND
METHODS
• Bacterial strains and growth conditions
• Plant material
• Pot experimental set-up
• Sodium content measurements
• Chlorophyll measurements
• Presence of bacterial endophytes in plant tissue

26. RESULTS
Table 1: Plants inoculated with P. fluorescens (YsS6) wild-type (YsS6WT), P.
fluorescens YsS6 ACC deaminase deficient mutant (YsS6M), P. migulae 8R6 wild-
type (8R6WT), and P. migulae 8R6 ACC deaminase deficient mutant (8R6M) in the
presence of no salt,165mM salt, or 185mM salt. Each value represents the mean
value. Data was collected on week 11 after seed sowing.

27. RESULTS

28. RESULT
Fig. 2. Effect of bacterial endophytes on the growth of tomato plants
in the presence and absence of salt

29. RESULT
Fig. 3. The effect of the bacterial endophytes on the growth of
tomato plant in the presence of 165 mM salt.

30. RESULT
Fig. 4. The effect of the bacterial endophytes on the growth of
tomato plant in the presence of 185 mM salt.

31. CONCLUSION:
• Bacterial endophytes are better adapted to various host
plants, they may be more beneficial in facilitating plant
growth than their counterpart, rhizospheric-binding
bacteria.
• The current study proved that ACC deaminase containing
bacterial endophytes increase the resistance of tomato
plants to salt and help them to grow under high salt stress
conditions.

32. CASE STUDY : 2

33. MATERIALS AND
METHODS
• Isolation and identification of ACC deaminase-containing rhizobacteria
• Plant material, growth conditions and irrigation treatments
• Preparation of mycorrhizal inoculum
• Inoculation treatments
• Experiment I
• Experiment II
• Plant growth and yield measurement
• AM fungi root colonization
• Biochemical analysis

34. RESULTS
Fig. 1. Effect of ACC deaminase-containing rhizobacterial inoculations on plant
growth.

35. RESULTS
Table 1: Effect of microbial inoculations on foliar nutrient uptake of Pisum plants
under different (No salt, 100 mM and 200 mM NaCl) salinity conditions of soil.

36. RESULTS

37. RESULTS
Fig. 2. Effect of microbial inoculations on total chlorophyll conditions of soil.

38. RESULTS
Fig. 3. Effect of microbial inoculations on total MDA (malondialdehyde)
conditions of soil.

39. RESULTS
Fig. 4. Effect of microbial inoculations on total proline content of Pisum plants under
different conditions of soil.

40. RESULTS
Fig. 4. Effect of microbial inoculations on ACC concentration enzymatic activities of
Pisum plants under different salinity conditions of soil.

41. RESULTS
Fig. 6. Effect of microbial inoculations ACS (ACC synthase) enzymatic activities of
Pisum plants under different salinity conditions of soil.
No change in value

42. RESULTS
Fig. 7. Effect of microbial inoculations on ACO (ACC oxidase) enzymatic activities of
Pisum plants under different salinity conditions of soil.

43. RESULTS

44. CONCLUSION:
A combination of SA3 + R + G acted synergistically and
therefore could be a sustainable alternate to mitigate salt stress
induced damage in pea plants which would probably establish a
new developmental equilibrium in order to cope with the initial
stress responses and in establishing plant stress tolerance.
It was established that in presence of ACC deaminase
containing bacteria, higher colonization of AMF and nodulation
of rhizobia could be achieved which is restricted because of high
ethylene concentration under stress.

45. Future prospects
A range of new innovative technologies needs
to be developed and implemented
Needs to implemented on large scale