This document summarizes synthetic seed production techniques for fruit crops. Synthetic seed contains a somatic embryo encapsulated in an artificial medium that provides nutrients. The process involves inducing somatic embryogenesis from explants, maturing the embryos, and encapsulating them. Embryos are encapsulated using methods like dropping into a calcium salt solution or molding in a gel. Synthetic seeds allow for mass propagation of identical genotypes at low cost and can be produced and stored year-round. While offering many advantages, synthetic seed production also faces challenges like low germination rates and lack of stress tolerance in embryos.

1. SYNTHETIC SEED; A NOVEL
TECHNIQUE OF PROPAGATION OF FRUIT
CROPS
TO

2. Speaker;
Amit kumar
Reg. : 17-01-02-09-26
M.Sc. (AG.) PBG
Seminar In-Charge;
Dr. D.K. Gothwal
Department of Plant
Breeding and Genetics
DEPARTMENT OF PLANT BREEDING AND GENETICS
S.K.N. COLLEGE OF AGRICULTURE JOBNER
SRI KARAN NARENDRA AGRICULTE UNIVERSITY

3. Introduction
Principle of synthetic seeds production
Procedure of synthetic seeds production
Types of synthetic seeds
Importance
Limitations
Conclusion

4. Among the innovative techniques of micro propagation the concept
of somatic embryogenesis with synthetic seed production or
artificial seed techniques is very important.
In simple words synthetic seed contains an embryo produced by
somatic embryogenesis enclosed within an artificial medium that
supplies nutrients and is encased in an artificial seed covering.

5.  Synthetic seed is encapsulated plant propagules (somatic
embryo / shoot bud) in a suitable matrix, containing
substances like nutrients, growth regulators, herbicides,
insecticides, fungicides and mycorrhizae which will help to
grow into a complete plantlet.
 It is a potential technique for plant multiplication and
preservation.

6. Why synthetic seeds in fruit crops?
In some of the fruit crops seeds propagation is not
successful due to;
Heterozygosity of seeds particularly in cross
pollinated crops
Minute seed size
Presence of reduced endosperm
No seeds are formed ,e.g.- banana, pineapple
low germination rate

7. A synthetic seed has following parts
7

8. Synthetic seeds Natural seeds
Produce from asexual process Produce from sexual process
Do not involve the fusion of
gametes
Involve the fusion of male and
female gametes
Produce from the vegetative
cells
Produce from the germ cells
Contains genetic constituents
from single parent
Contains genetic constituents
from both parents
No genetic recombination take
place
Genetic recombination takes
place

9. Effect of endosperm and encapsulation on zygotic and
somatic embryo germination and conversion
Embryos Form % Germination % Conversion
Zygotic
Non
encapsulated
100 100
Encapsulated 100 93.3
Somatic
Non
encapsulated
93.3 93.3
Encapsulated 100 100

10. Synthetic seed contains an embryo produced by somatic
embryogenesis enclosed with in an artificial medium that supplies
nutrients and artificial seed covering. As a result, somatic embryos
possess a clones of identical genotype.

11. 1. Somatic embryos
2. Gelling agent
3. Artificial endosperm
Basic requirement for synthetic seed production

12.  The process of embryo development from a somatic cell is
called somatic embryogenesis.
 Under certain exceptional conditions, the cells behave like a
zygote and develop into embryo like structure in culture in vitro.
Since embryo like structures derived from the somatic cells of
plant, is known as somatic embryogenesis.

13. Types of somatic embryogenesis
1. Direct embryogenesis
It refers to the development of an embryo directly from the
original ex-plant tissue without an intervening callus phase.
2. Indirect embryogenesis
It is the formation of embryos from callus or cell
suspension, group of cells is known as indirect embryogenesis.

14. Different stages of embryo development

15. Invitro propagules for
encapsulation
Fruit crop
Somatic embryos Papaya, Mango,
Auxiliary buds/ adventitious buds Grape, Citrus, Pineapple
Shoot tip Banana, Apple, Kiwifruit

16.  Somatic embryos are first hardened to withstand desiccation
and then these hardened embryos are encapsulated artificially
with the use of appropriate growth medium.
 Such types of synthetic seeds are produced only in plant
species whose somatic embryos are desiccation tolerant.
1. Desiccated synthetic seed:

17.  The gel used to enclose somatic embryo remains hydrated.
Various water soluble gels can be used for the purpose of
encapsulation, like gel rite, locust bean gum, sodium alginate
with gelatin. However, alginate is the most suitable gel.
 Hydrated synthetic seeds are produced in those plant species
where the somatic embryos are recalcitrant and sensitive to
desiccation.

18. STEPS OF SYNTHETIC SEED PRODUCTION
Select of suitable ex-plant
Establishment of somatic embryogenesis
Induction of somatic embryogenesis
Maturation of somatic embryo
Encapsulation of somatic embryos
Evolution of embryoid and plant conversion
Planting in fields/ green house

19. Procedure of synthetic seed production

20. Gel (concentration) (% w/v) Complex Agents Consternation
(µM)
Sodium alginate
Sodium alginate
with gelatin
Carrageenan
Locust bean gum
Gelrite
(0.5-5.0)
(2.0)
(0.2-0.8)
(0.4–1.0)
0.25
Calcium salt
Calcium Chloride
Potassium Chloride
Ammonium Chloride
(30-100)
(30-100)
(500)
(500)

21. Non damaging to the somatic embryos.
Durable during storage, transportation and planting.
Protect the embryo while allowing the germination and
conversion.
Containments nutrients, microorganisms necessary for
germination.
Enable the formation of mono- embryonic synthetic seeds.
Sowable using farm machinery.

22. Encapsulation/ Coating of synthetic seeds
Encapsulation is necessary to produce and protect synthetic seeds.
The encapsulation is done by various types of hydro gels which are
water soluble.
There are different method of encapsulation
1.Gel encapsulation method via dropping method
2.Automatic encapsulation process
3.Mass balance concept

23. 1. Gel complexing via a dropping procedure:
Drip 2 per cent LF 60 Sodium
alginate from a reparatory funnel
into a 100 mM calcium nitrate
solution. As the sodium alginate
dropped from at the tip of the
funnel the somatic embryos are
inserted.
The encapsulated embryos
complex in calcium salt for 20
minutes, after they are rinsed in
water and stored in a air tight
container. This is slow method
but most useful encapsulation
system.

24. It is the recent and quick method of artificial seed production.
An encapsulation machine can be used successfully to
encapsulate the somatic embryos, e.g., alfalfa.
For rapid drying and the thickness of the alginate capsules, a
hydrophobic coating is required for mechanical handling.
For coating an Elvax 4260 Copolymer (Dupont) is suitable.

25. Automatic encapsulated process:-
a) Alginate solution with embryo
is feed from supply tank.
b) Alginate capsules were planted
in speeding trays using vacuum
seeders.
c) The capsules are planted in the
field using a stanhay planter.
d) A hydrophobic coating is
required for mechanical
handling.

26.  The somatic embryos are mixed with sodium alginate (2 %) and
the suspension is dropped into the calcium salts solution
(200mM).
 The principle involved is when sodium alginate dropped into the
calcium salt solutions it forms round firm beads due to the ion
exchange between Na+ in sodium alginate and Ca2+ in calcium
salt solutions and sodium alginate form calcium alginate in 20-
30 minutes.

27. 3.Mass balance concept
 An additional concept that has greatly aided the improvement of
artificial seed performance is mass balance.
 Mass balance is considered the amount of tissue at the
beginning of the experiment and the number of high quality
plants produced at the end of it.
 Simply emphasizing the number of embryos per gram of fresh
callus.

28. Methods for artificial seed production
There are two methods of artificial seed production
1. Dropping method
2. Molding method

29.  Somatic embryos are dipped in hydro gel like alginate – sodium
alginate, agar from sea weed, guar gum, locust bean gum etc.
which prepared in MS basal medium solution.
 Burette is filled with sodium alginate solution (1 – 5%), dripped
into a calcium nitrate solution (100mM) drop by drop. Somatic
embryo is inserted into the drop formed at the burette tip.
 Sodium alginate drop along with SE falls into the solution of
calcium nitrate.

30.  Useful adjuvant like growth regulators, herbicides,
insecticides, fungicides and mycorrhizae such can be
supplied to the SE while encapsulation along with the
matrix.
 This is suitable for embryo / auxiliary / apical / adventitious
buds.

31.  This method follows simple procedure of mixing of embryos
with temperature dependent gel (e.g. gel rite, agar). get coated
with the gel at lowering of the temperature.

32. Reduces cost if transplants.
Production of large number of identical embryos.
Determine role of endosperm in embryo development and
germination.
There is no problem of seed dormancy.
Synthetic seed applicable for large scale monocultures as well
as mixed genotypes plantation.

33. There are potential advantages of artificial seed technology
especially for fruit tree genetic engineering.
Propagation with the low cost, high volume capabilities of
seed propagation..
These seeds can be produced within a short time whereas
natural seed are the end product of complex reproductive
process and wait for a long time for developing a new
variety.
It can be produced at any time and any season of a year.
Also helpful in preserving germplasm.

34. costly
Anomalous and asynchronous development of somatic embryos
Poor germination due to lack supply of nutrients, insufficient
oxygen, microbe invasion and mechanical damage of somatic
embryos.
Lack of dormancy and stress tolerance in somatic embryos that
limit the storage of synthetic seeds
Special skills are required to carry out the work.

35. Artificial seeds that are stable for several months require the
procedures for making the embryos quiescent.
Need to be protected against desiccation.
Recovery of plants are very low due to incomplete embryo
formation or difficulties in creating an artificial endosperm.
The embryo must be protected against microorganisms.
Problems

36. Different stages of somatic embryogenesis in mango ( Mangifera
indica L) var. Kurukkan for synthetic seed production

38. Banana are triploiody and are propagated by
vegetative mean.
In addition to this polyploidy and sterility often
hampers the breeding programme for the
developments of superior banana varieties.
Thus somatic embryogenesis leading to
embryos production and plant regeneration is
very useful not only for large scale clonal
propagation but also provide useful system for
genetic manipulation and production of
synthetic seed in banana.

39. Encapsulated micro shoots of banana Grand Naine

40. Conclusion
In mango basal RO medium gave better response for culture
establishment and embryo induction. Longer incubation in presence
of low 2, 4-D medium registered higher embryo development. where
as full strength of B5 micro salt gives better response to germination
and conversion percentage.
In banana germination of synthetic seed was maximum when
treated with benzyl adenine @5mg/l for 5 minute with single layer of
charcoal encapsulation.