This document summarizes a presentation on the use of microbial seed coating as an emerging strategy for organic vegetable production. It discusses the increasing global population and need for sustainable food production. Microbial seed coating can help control seed-borne diseases organically by coating seeds with beneficial microbes. The presentation describes different types of seed coatings, ingredients in the coatings including microbes, and mechanisms by which microbes in coatings can promote plant growth and health. Case studies demonstrate the effectiveness of microbial seed coatings in reducing disease and improving growth of tomato and onion seeds and seedlings. The presentation concludes that microbial seed coating has high potential for use in vegetable and other horticultural crops.

1. Minor Credit Seminar
Department of Horticulture
Microbial seed coating- an emerging strategy
towards organic vegetable production
Presenter: Miss Mehjebin Rahman
2019-ADJ-60
Ph. D. 2nd year 1st Semester
Major Advisor: Dr. Pradip Kr. Borah

2. 19/01/2021, Minor Credit Seminar
Department
of
Horticulture,
AAU,
Jorhat
Introduction
Chemical pesticides
Initiatives by govt
Seed borne diseases
Organic practices
Microbial seed coating
Coating in vegetable
Types of seed coating
Seed coat ingredients
Role of microbes
Limitations
Advantages
Mechanism
Case study
Future thrust
Conclusion

3. 19/01/2021, Minor Credit Seminar
Department
of
Horticulture,
AAU,
Jorhat
1800, 1
1930, 2
1960, 3
1970, 6
By 2050,
Human population 10
billion.
Global food production
70%
195.9 million undernourished
people lacking sufficient food to
meet their daily nutritional
requirements

4. 19/01/2021, Minor Credit Seminar
Department
of
Horticulture,
AAU,
Jorhat
Green
revolution
HYV seeds
Irrigation
Fertilizers
(chemical)
CAD
Land
reforms
Agricultural
credit
Rural
electrification
Rural roads
and
marketing
Farm
mechanizations
Insecticides
and
pesticides

5. 19/02/2021, Minor Credit Seminar
Department
of
Horticulture,
AAU,
Jorhat

6. List of the 10 most contaminated food items by The Environmental
Working Group (EWG) :
Strawberries, Spinach, Nectarines, Apples, Grapes, Peaches, Cherries
Pears, Tomatoes, Celery
19/02/2021, Minor Credit Seminar
Department
of
Horticulture,
AAU,
Jorhat
Circulates through
blood and reach
neurons and brain
cells
Pesticides and
fungicides

7. 19/02/2021, Minor Credit Seminar
Department
of
Horticulture,
AAU,
Jorhat

8. 19/02/2021, Minor Credit Seminar
Department
of
Horticulture,
AAU,
Jorhat
The government through programmes like Paramparagat Krishi Vikas
Yojana (PKVY) is encouraging farmers to adopt organic farming for
“Doubling Farmers’ income by 2022”
PM
Honourable P.M Narendra Modi said- We clearly need a second green
revolution that is more broad-based, more inclusive and more
sustainable; we need to produce more without depleting our natural
resources any further
He has called for adoption of organic and natural farming in a cluster
based approach and said Indian Council of Agricultural Research
(ICAR) has developed a geo-referenced Organic Carbon Map of India
and identified 88 bio control agents and 22 Bio pesticides which can
promote organic agriculture.

9. 19/02/2021, Minor Credit Seminar
Department
of
Horticulture,
AAU,
Jorhat
Designing the blueprint of horticulture in the coming years
need to go for sustainable approaches which enhance the
yield of plants while still maintaining the decorum of
sustainability.

10. 19/02/2021, Minor Credit Seminar
Department
of
Horticulture,
AAU,
Jorhat
Seed is a common carrier of plant
pathogens and pathogen free seed
is the important input material for
agriculture (Senthamarai MP et al.,
2011)
Over 200 diseases have been
reported to affect the different
vegetables in the world. Among
them the seed-borne pathogens
mostly fungi play a vital role in
disease development(Hossain
GMK et al., 2015)

11. 19/02/2021, Minor Credit Seminar
Department
of
Horticulture,
AAU,
Jorhat

12. 19/02/2021, Minor Credit Seminar
Department
of
Horticulture,
AAU,
Jorhat
Soil borne diseases of vegetable crops
Fusarium wilt of melon Bacterial leaf sopt in lettuce Bacterial soft rot of carrot
White mold of cabbage
Root and hypocotyl rot of
radishes
Late blight of tomato

13. 19/02/2021, Minor Credit Seminar
Department
of
Horticulture,
AAU,
Jorhat
Seed borne diseases of vegetable crops
Fusarium wilt of tomato
Bacterial wilt of tomato
Black rot of cabbage
Botrytis Neck rot of onion
Phomopsis blight of brinjal Black leg of cabbage

14. 19/02/2021, Minor Credit Seminar
Department
of
Horticulture,
AAU,
Jorhat SUSTAINABLE PRACTICES
for seed-borne diseases
Seed treatments
Proper seed storage
Variety selection and grafting
Organic amendments
Optimum plant spacing
Sanitation
Coating

15. 19/02/2021, Minor Credit Seminar19
Department
of
Horticulture,
AAU,
Jorhat
Seed coating
Film coating is the technique of encapsulating seeds with
a thin layer of synthetic slurry form consisting of
polymers, plasticizers, pigments, and solvents, using
rotating drum machines.The thin coating layer does not
greatly change the size and shape of seeds, however, it
enhances handling characteristics of seeds while
eliminating or minimizing product (e.g. pesticides,
biological and micronutrients) dust-off (Taylor et al.,
2001).

16. 19/02/2021, Minor Credit Seminar
Department
of
Horticulture,
AAU,
Jorhat
Application of microbial seed coating technology in
vegetable crops
Onion seeds Sunflower seeds
Okra seeds
Chili seeds
Tomato seeds
Lettuce seeds
Watermelon seeds

17. 19/02/2021, Minor Credit Seminar
Department
of
Horticulture,
AAU,
Jorhat
Seed coating types
Seed dressing
Film coating
Encrusting
Pelleting

18. 19/02/2021, Minor Credit Seminar
Lime
Department
of
Horticulture,
AAU,
Jorhat
The composition of Microbe Seed coating
2. Binder 3. Filler 4. Microbial inoculum
1. Seed
Biochar
Chitosan
Xanthan
gum
Gum
arabic
Peat
Talc
CMC
Alginate
beads

19. 19/02/2021, Minor Credit Seminar
Department
of
Horticulture,
AAU,
Jorhat
Seed coating agents
Markers
Micro-organisms
Growth
stimulators
Humic acids,
Phytohormones
Algae extracts
Plant growth-promoting
bacteria
Arbuscular mycorrhizal fungi
Micronutrients

20. 19/02/2021, Minor Credit Seminar
Department
of
Horticulture,
AAU,
Jorhat
MICROBES are the
best players finding
their roles in plant
growth promotion and
also stress management.

21. 19/02/2021, Minor Credit Seminar
Department
of
Horticulture,
AAU,
Jorhat
Microbes to
Feed the World
without being
Detrimental to
Environment
Act as
BIOFERTILIZERS
Rhizomediators
Act as
BIOSTIMULATOR
The crop
protectants-
BIOPESTICIDES

22. 19/02/2021, Minor Credit Seminar
Department
of
Horticulture,
AAU,
Jorhat
How PBM in seed coat works in vegetable microbe seed coats
Extended
release of
PGPM
PBM in ISR responses
Indirect mechanism
Direct mechanism
Siderophore production
Competition
Antibiotics
Lytic enzymes
HCN
VOCs
PBM
Pathogens
N2 fixation
Phytohormones
Water soluble B
vitamins
P solubilization
K solubilization
PBM in plant growth promotion Nutrient
uptake
Photosynthates
PBM in plant protection

23. 19/02/2021, Minor Credit Seminar
.
Department
of
Horticulture,
AAU,
Jorhat
•Colonization of microbe in plant or soil,
•Early developmental stages of BCA in
•Environmental factors affecting
performance
•Degradation of foliar residues by solar
UV
Why microbial
biopesticides are
a failure in field?

24. 19/02/2021, Minor Credit Seminar
Department
of
Horticulture,
AAU,
Jorhat
Advantages of microbe coated seeds over other
organic approaches
 Protect the functional microbes
 Precision farming
 Extended-release
• Right time-Right place-Right amount
 Protect them during seed storage
• Enhanced mechanism of PGPM inoculants

25. 19/02/2021, Minor Credit Seminar
Department
of
Horticulture,
AAU,
Jorhat
MICROBIAL SEED COATING:
A tool for successfully delivering microbes
To promote crop growth and stress tolerance
High potential for VEGETABLES AND OTHER HORTICULTURAL CROPS.
The global seed coating market is projected to surge at a CAGR of
8.10% to reach a market size of USD4.287 billion in 2025 from a market
size of USD2.686 billion in 2019.
Agribusiness firms Novozymes and Monsanto world’s biggest field-test
program of seeds laced with promising microbes

26. 19/02/2021, Minor Credit Seminar
Department
of
Horticulture,
AAU,
Jorhat

27. 19/02/2021, Minor Credit Seminar
Department
of
Horticulture,
AAU,
Jorhat

28. 19/01/2021, Minor Credit Seminar
Department
of
Horticulture,
AAU,
Jorhat
1000 g of pure vermicompost was grinded into fine powder and steam
sterilized at 121°C for 20 min then dried for 12 h at 50°C before use to
maintain 25% of moisture content.
Tomato cv. Arka vikas seeds was used.
Seeds were moistened with minimal amount of water and coated uniformly
with individual formulations @ 20g/kg of seed.
Seeds were shade dried for 30 min to reduce the moisture content upto20%.
T1-500ml of OTPB1 suspension
T2- 500ml of OTPB3 suspension
T3-microbial consortium of 250ml of OTPB1 suspension and 250ml of
OTPB3 spore
Later sown in plastic pot trays containing 96 cavities with 10 cm diameter,
filled with well composted and sterilized coco peat (soilless growth media).

29. 19/02/2021, Minor Credit Seminar
Department
of
Horticulture,
AAU,
Jorhat
Seeds coated with microbial consortium and vermicompost (T3) gave the
best results in all parameters of seedlings growth and induction of three
defense enzyme activities.
(T1)
(T2)
(T3)
(T3)
(T1)
(T2)

30. 19/02/2021, Minor Credit Seminar
Department
of
Horticulture,
AAU,
Jorhat
Seeds coated with microbial consortium and vermicompost (T3) showed
least infection of both the pathogens Alternaria solani and Phytophthora
infestans in tomato seedlings
(T3)
(T2)
(T1)

31. 19/02/2021, Minor Credit Seminar
Department
of
Horticulture,
AAU,
Jorhat

32. 19/02/2021, Minor Credit Seminar
Department
of
Horticulture,
AAU,
Jorhat

33. 19/02/2021, Minor Credit Seminar
Department
of
Horticulture,
AAU,
Jorhat
Endophytic bacterial isolate SuRW02 was used as a bacterial cell suspension
at 1x108 cfu/65g seed. Coating was done with peat moss.
Tomato seeds were cleaned with 0.6 percent sodium hypochlorite for 5
minutes, then washed with distilled water, sterilized 3 times and dried in
laminar airflow.
Experiment was laid out in a completely randomized design (CRD) with 4
treatments and 8 replications as follows:-
T1- non-coated seed (NCS),
T2- coated seed (CS),
T3- coated seed with endophytic bacteria (CS+B)
T4- coated seed with Captan (CS+C).
Coated seeds were stored at cool temperatures in a refrigerator.

34. 19/02/2021, Minor Credit Seminar
Department
of
Horticulture,
AAU,
Jorhat
Seeds coated with Captan followed by Endophytic bacteria showed least disease
incidence of Fusarium wilt in tomato seedlings
Seeds coated with Endophytic bacteria gave maximum height of shoot, fresh
weight, stem diameter, yield weight and TSS in Fusarium inoculated plants.

35. 19/02/2021, Minor Credit Seminar
Department
of
Horticulture,
AAU,
Jorhat

36. 19/02/2021, Minor Credit Seminar
Department
of
Horticulture,
AAU,
Jorhat
Pelleting materials: Cow dung, vermicompost, clay soil in the ratio of 3:2:1
volume basis. Pelleting material was put manually layer after layer till the
desired pellet size was achieved
Fresh cultivar Arka Kalyan were used for this study. The seeds were cleanseeds
of onion ed and graded to get maximum germination. One seed was
incorporated into one pellet
Adhesive materials: Methyl cellulose (1.5%) and polyvinyl alcohol (2.0%).
Adhesives were sprayed uniformly on seed surface in very fine droplets using
spray gun.
Non-pelleted (left) and pelleted (right) onion seed

37. 19/02/2021, Minor Credit Seminar
Department
of
Horticulture,
AAU,
Jorhat
Micronutrients such as zinc sulphate 5% and boric acid 1% and microbial
consortium were incorporated concurrently along with pelleting material.
(Microbial consortium I) :Actinomycetes + and Bacillus aryabhatai
(Microbial consortium II) :Bacillus subtilis + Trichoderma harizianum
Combinations:
1) Pelleted only; 2) Pelleted with Zn and B; 3) Pelleted with Zn, B and
microbial consortium I; 4) Pelleted with Zn, B and microbial consortium II; 5)
Control (non-pelleted).
The moisture content of pellets was determined by standard oven method by
drying at 103 °C for 17 hr
The pelleted and nonpelleted seeds were stored in cloth bags under ambient for
12 months to study the effect of pelleting on their storage.

38. 19/02/2021, Minor Credit Seminar
Department
of
Horticulture,
AAU,
Jorhat
These seeds were placed in germination chamber maintained at alternate
temperature of 20-30 °C and RH 90%. First count was recorded on 6th day and
final germination was recorded on 12th day after incubation.
The data on seed quality parameters such as 100 seed weight, first count, final
germination, abnormal seedlings, seedling length and vigour index were
analyzed by CRD and field data on crop stand, plants with bulbs, yield/plot and
estimated yield/ha by RCBD ANOVA.

39. 19/02/2021, Minor Credit Seminar
Department
of
Horticulture,
AAU,
Jorhat
Control (non-pelleted) showed highest seed germination, seedling length and seed
vigor but highest no. of abnormal seedlings were present. Whereas seeds pelleted
with microbial consortia gave least no of abnormal seedlings.

40. 19/02/2021, Minor Credit Seminar
Department
of
Horticulture,
AAU,
Jorhat

41. 19/02/2021, Minor Credit Seminar
Department
of
Horticulture,
AAU,
Jorhat
Seeds of okra (Abelmoschus esculentus L.) and sunflower (Helianthus
annus L.) were surface sterilized with 1% Ca(OCl)2 for three minutes,
rinsed thoroughly in running tap water and dried aseptically
The seeds were treated with microbial antagonists viz, B. thuringiensis,
R. meliloti, A. niger, T. harzianum separately by using 1% and 2%
sugar, mollases, glucose and gum arabic solution as a sticker.
5 seeds/pot were sown in 8 cm diameter plastic pots, each pot
containing 300g soil.
There were three replicates of each treatment and pots without
antagonists and without seed coating material served as control

42. 19/02/2021, Minor Credit Seminar
Department
of
Horticulture,
AAU,
Jorhat
Plants were uprooted after 30 days. Plant growth parameters in terms of root
length, shoot length and fresh weights of root, shoot and incidence of root
infecting fungi were recorded.
After 30 days, roots of okra and sunflower were washed in running tap water,
surface sterilized in 1% Ca(OCl)2 and then five 1 cm long root pieces were
transferred on PDA plates containing penicillin @ 100,000/litre and
streptomycin @ 20mg/l.
Petri plates were incubated for 5 days, at room temperature to confirm
infection of roots by root infecting fungi.

43. 19/02/2021, Minor Credit Seminar
Department
of
Horticulture,
AAU,
Jorhat

44. 19/02/2021, Minor Credit Seminar
Department
of
Horticulture,
AAU,
Jorhat

45. 19/02/2021, Minor Credit Seminar
Department
of
Horticulture,
AAU,
Jorhat

46. 19/02/2021, Minor Credit Seminar
Department
of
Horticulture,
AAU,
Jorhat

47. No significant increase in germination was observed when seeds of
okra and sunflower were treated with microbial antagonists using 1 and
2% of sugar, mollases, glucose and gum arabic as stickers.
The 2% gum Arabic solution showed more promising results in
increasing shoot length, shoot weight, root length, root weight.
Also in reducing infection of root rot fungi viz., M. phaseolina, R.
solani and Fusarium spp., on okra.
T. harzianum showed most effective results in increasing germination
of sunflower and okra seeds.
Increase in shoot length, shoot weight, root length and root weights was
also observed.
Significant reduction in infection of R. solani, M. phaseolina and
Fusarium spp., where seeds of okra and sunflower were treated with T.
harzianum and B. thuringiensis
Among the coating agents
Among the BCA
19/02/2021, Minor Credit Seminar
Department
of
Horticulture,
AAU,
Jorhat

48. 19/02/2021, Minor Credit Seminar
Department
of
Horticulture,
AAU,
Jorhat
Future thrust
Nascent stage in
horticultural crops
Lab-to-Land
Dissemination
of technology
Skill development
and
entrepreneurship

49. 19/02/2021, Minor Credit Seminar
Department
of
Horticulture,
AAU,
Jorhat
It is a largely untapped area that deserves major research efforts
Achieving the craze for organic faming that is popularizing worldwide
Time saving and cost effective.