NCERT Textbook: Plant Tissue Culture | Biotechnology for Class 12 - NEET PDF Download

 Page 1


Plant tissue culture (PTC) refers to the cultivation of 
undifferentiated plant cells, tissues or organs on synthetic 
media under aseptic environment and suitable controlled 
physical conditions. It is an important tool for both basic 
research as well as commercial applications. Plant tissue 
culture is based upon the unique characteristic of a plant  
cell, i.e., totipotency. Totipotency is the ability of a vegetative 
cell to divide and differentiate into any type of specialised 
cell or to regenerate into a whole plant.
7.1 Historical Pers Pective In 19
th
 century, German scientists Theodor Schwann 
and Matthias Schleiden, drew attention to the fact that a 
cell is the basic unit of life and has the capacity to divide 
and grow. During 1890’s, Gottlieb Haberlandt (German 
Botanist), pioneered the ??eld of PTC with his idea to achieve 
continuous cell divisions in plant cells on nutrient media. 
He attempted to culture fully differentiated plant cells on 
simple nutrient media. He laid down several principles of 
plant tissue culture in 1902, like plant cells are capable 
of resuming uninterrupted growth, or it is possible to 
7.1 Historical 
Perspective
7.2 Cell and Tissue 
Culture Techniques
7.3 Nutrient Media
7.4 Culture Types
7.5 Applications of 
Plant Cell and 
Tissue Culture  
Plant Tissue Culture
7
Chapter 
Chapter 7_Plant Tissue Culture.indd   167 23-01-2025   11:23:56
Reprint 2025-26
Page 2


Plant tissue culture (PTC) refers to the cultivation of 
undifferentiated plant cells, tissues or organs on synthetic 
media under aseptic environment and suitable controlled 
physical conditions. It is an important tool for both basic 
research as well as commercial applications. Plant tissue 
culture is based upon the unique characteristic of a plant  
cell, i.e., totipotency. Totipotency is the ability of a vegetative 
cell to divide and differentiate into any type of specialised 
cell or to regenerate into a whole plant.
7.1 Historical Pers Pective In 19
th
 century, German scientists Theodor Schwann 
and Matthias Schleiden, drew attention to the fact that a 
cell is the basic unit of life and has the capacity to divide 
and grow. During 1890’s, Gottlieb Haberlandt (German 
Botanist), pioneered the ??eld of PTC with his idea to achieve 
continuous cell divisions in plant cells on nutrient media. 
He attempted to culture fully differentiated plant cells on 
simple nutrient media. He laid down several principles of 
plant tissue culture in 1902, like plant cells are capable 
of resuming uninterrupted growth, or it is possible to 
7.1 Historical 
Perspective
7.2 Cell and Tissue 
Culture Techniques
7.3 Nutrient Media
7.4 Culture Types
7.5 Applications of 
Plant Cell and 
Tissue Culture  
Plant Tissue Culture
7
Chapter 
Chapter 7_Plant Tissue Culture.indd   167 23-01-2025   11:23:56
Reprint 2025-26
Biotechnology XII 168
regenerate embryos from vegetative cells. Later, all of the 
predictions made by him were found to be true as they 
were con??rmed experimentally by other researchers. This 
is the reason he is regarded as the ‘Father of Plant Tissue 
Culture’. 
During 1902–1930s, several attempts were made 
to culture the isolated plant tissues, like root or shoot 
tips, and continuously growing plant cell cultures were 
established. The discovery that vitamins and natural 
auxins are necessary for the growth of plant tissues on 
synthetic media gave a signi??cant boost to PTC. During 
1940s –70s, extensive studies were performed to improve 
the existing techniques for developing new methods to 
optimise the nutrient media components for culturing 
plant tissues. Coconut water stimulated the development 
of young embryos and was used with nutrient media for 
in vitro cultures. Later, other natural supplements, like 
corn milk, orange juice, etc., were used for developing 
callus culture of several species, like woody plants and 
herbaceous dicot plants. During 1950s, adenine, kinetin 
and high levels of phosphate were used in nutrient media 
that resulted in the successful initiation of cultures 
from non-meristematic tissues and production of shoots 
or roots. It was also established during this time that the 
morphogenic fate of cultured cells was directly in??uenced 
by the exogenous balance of auxins and kinetin. It was 
suggested that a relatively high level of auxin to kinetin 
causes rooting, while the reverse led to shooting and 
intermediate levels were responsible for the proliferation of 
callus. This led to the regeneration of new plants through 
tissue culture using various plant tissues or organs as 
starting material in several commercial applications. An 
arti??cial culture medium developed by Murashige and 
Skoog (MS) was successful for culturing plants and resulted 
in the initiation of tissue culture from a large number of 
plant species. MS media composition is the most widely 
used nutrient media in plant tissue cultures.
Chapter 7_Plant Tissue Culture.indd   168 23-01-2025   11:23:56
Reprint 2025-26
Page 3


Plant tissue culture (PTC) refers to the cultivation of 
undifferentiated plant cells, tissues or organs on synthetic 
media under aseptic environment and suitable controlled 
physical conditions. It is an important tool for both basic 
research as well as commercial applications. Plant tissue 
culture is based upon the unique characteristic of a plant  
cell, i.e., totipotency. Totipotency is the ability of a vegetative 
cell to divide and differentiate into any type of specialised 
cell or to regenerate into a whole plant.
7.1 Historical Pers Pective In 19
th
 century, German scientists Theodor Schwann 
and Matthias Schleiden, drew attention to the fact that a 
cell is the basic unit of life and has the capacity to divide 
and grow. During 1890’s, Gottlieb Haberlandt (German 
Botanist), pioneered the ??eld of PTC with his idea to achieve 
continuous cell divisions in plant cells on nutrient media. 
He attempted to culture fully differentiated plant cells on 
simple nutrient media. He laid down several principles of 
plant tissue culture in 1902, like plant cells are capable 
of resuming uninterrupted growth, or it is possible to 
7.1 Historical 
Perspective
7.2 Cell and Tissue 
Culture Techniques
7.3 Nutrient Media
7.4 Culture Types
7.5 Applications of 
Plant Cell and 
Tissue Culture  
Plant Tissue Culture
7
Chapter 
Chapter 7_Plant Tissue Culture.indd   167 23-01-2025   11:23:56
Reprint 2025-26
Biotechnology XII 168
regenerate embryos from vegetative cells. Later, all of the 
predictions made by him were found to be true as they 
were con??rmed experimentally by other researchers. This 
is the reason he is regarded as the ‘Father of Plant Tissue 
Culture’. 
During 1902–1930s, several attempts were made 
to culture the isolated plant tissues, like root or shoot 
tips, and continuously growing plant cell cultures were 
established. The discovery that vitamins and natural 
auxins are necessary for the growth of plant tissues on 
synthetic media gave a signi??cant boost to PTC. During 
1940s –70s, extensive studies were performed to improve 
the existing techniques for developing new methods to 
optimise the nutrient media components for culturing 
plant tissues. Coconut water stimulated the development 
of young embryos and was used with nutrient media for 
in vitro cultures. Later, other natural supplements, like 
corn milk, orange juice, etc., were used for developing 
callus culture of several species, like woody plants and 
herbaceous dicot plants. During 1950s, adenine, kinetin 
and high levels of phosphate were used in nutrient media 
that resulted in the successful initiation of cultures 
from non-meristematic tissues and production of shoots 
or roots. It was also established during this time that the 
morphogenic fate of cultured cells was directly in??uenced 
by the exogenous balance of auxins and kinetin. It was 
suggested that a relatively high level of auxin to kinetin 
causes rooting, while the reverse led to shooting and 
intermediate levels were responsible for the proliferation of 
callus. This led to the regeneration of new plants through 
tissue culture using various plant tissues or organs as 
starting material in several commercial applications. An 
arti??cial culture medium developed by Murashige and 
Skoog (MS) was successful for culturing plants and resulted 
in the initiation of tissue culture from a large number of 
plant species. MS media composition is the most widely 
used nutrient media in plant tissue cultures.
Chapter 7_Plant Tissue Culture.indd   168 23-01-2025   11:23:56
Reprint 2025-26
Plant Tissue Culture
169
Box 1
Major landmark discoveries in plant tissue culture and its applications
1902
Gottlieb Haberlandt proposed that plant cells can be cultured on arti??cial 
media and developed the concept of in vitro cell culture.
1904
Hanning initiated work on excised embryo culture and later cultured 
embryos from several cruciferous species.
1922
Kotte and Robbins suggested root and stem tips as possible explants to 
initiate in vitro tissue culture.
1926 Went discovered the ??rst plant growth hormone, i.e., Indole Acetic Acid (IAA).
1934
The role of vitamin B as growth supplement in plant tissue culture was 
reported by White. He could successfully establish continuous growing 
cultures from tomato root tips.
1937 White formulated the ??rst synthetic plant tissue culture medium (WM).
1941
Johannes Van Overbeek introduced coconut water as a media component 
and demonstrated its bene??cial effects on in vitro tissue culture.
1946 Ball raised whole plants from shoot tips of Lupinus.
1954 Muir successfully induced cell division in mechanically isolated single cells.
1955
Skoog and Miller reported the discovery of Kinetin, which is a type of 
cytokinin and promotes cell division.
1957
Skoog and Miller described chemical control hypothesis of root and shoot 
differentiation by manipulating the ratio of concentrations of auxin and 
kinetin.
1962
Murashige and Skoog formulated MS medium with higher salt 
concentrations.
1964
Guha and Maheshwari produced the ??rst androgenic haploid Datura plant 
by anther culture.
1971
Protoplasts were subcultured in vitro, and plants were regenerated from 
their culture.
1972
Protoplast from two different species of Nicotiana were isolated, fused 
together and somatic hybrids were generated successfully.
1976
Gynogenic haploid plants were successfully cultured from unfertilised 
ovaries of barley by San Noeum.
1978
Melchers and colleagues produced ‘Pomato’, which was a hybrid of potato 
and tomato, and was produced through somatic hybridisation. 
Chapter 7_Plant Tissue Culture.indd   169 23-01-2025   11:23:56
Reprint 2025-26
Page 4


Plant tissue culture (PTC) refers to the cultivation of 
undifferentiated plant cells, tissues or organs on synthetic 
media under aseptic environment and suitable controlled 
physical conditions. It is an important tool for both basic 
research as well as commercial applications. Plant tissue 
culture is based upon the unique characteristic of a plant  
cell, i.e., totipotency. Totipotency is the ability of a vegetative 
cell to divide and differentiate into any type of specialised 
cell or to regenerate into a whole plant.
7.1 Historical Pers Pective In 19
th
 century, German scientists Theodor Schwann 
and Matthias Schleiden, drew attention to the fact that a 
cell is the basic unit of life and has the capacity to divide 
and grow. During 1890’s, Gottlieb Haberlandt (German 
Botanist), pioneered the ??eld of PTC with his idea to achieve 
continuous cell divisions in plant cells on nutrient media. 
He attempted to culture fully differentiated plant cells on 
simple nutrient media. He laid down several principles of 
plant tissue culture in 1902, like plant cells are capable 
of resuming uninterrupted growth, or it is possible to 
7.1 Historical 
Perspective
7.2 Cell and Tissue 
Culture Techniques
7.3 Nutrient Media
7.4 Culture Types
7.5 Applications of 
Plant Cell and 
Tissue Culture  
Plant Tissue Culture
7
Chapter 
Chapter 7_Plant Tissue Culture.indd   167 23-01-2025   11:23:56
Reprint 2025-26
Biotechnology XII 168
regenerate embryos from vegetative cells. Later, all of the 
predictions made by him were found to be true as they 
were con??rmed experimentally by other researchers. This 
is the reason he is regarded as the ‘Father of Plant Tissue 
Culture’. 
During 1902–1930s, several attempts were made 
to culture the isolated plant tissues, like root or shoot 
tips, and continuously growing plant cell cultures were 
established. The discovery that vitamins and natural 
auxins are necessary for the growth of plant tissues on 
synthetic media gave a signi??cant boost to PTC. During 
1940s –70s, extensive studies were performed to improve 
the existing techniques for developing new methods to 
optimise the nutrient media components for culturing 
plant tissues. Coconut water stimulated the development 
of young embryos and was used with nutrient media for 
in vitro cultures. Later, other natural supplements, like 
corn milk, orange juice, etc., were used for developing 
callus culture of several species, like woody plants and 
herbaceous dicot plants. During 1950s, adenine, kinetin 
and high levels of phosphate were used in nutrient media 
that resulted in the successful initiation of cultures 
from non-meristematic tissues and production of shoots 
or roots. It was also established during this time that the 
morphogenic fate of cultured cells was directly in??uenced 
by the exogenous balance of auxins and kinetin. It was 
suggested that a relatively high level of auxin to kinetin 
causes rooting, while the reverse led to shooting and 
intermediate levels were responsible for the proliferation of 
callus. This led to the regeneration of new plants through 
tissue culture using various plant tissues or organs as 
starting material in several commercial applications. An 
arti??cial culture medium developed by Murashige and 
Skoog (MS) was successful for culturing plants and resulted 
in the initiation of tissue culture from a large number of 
plant species. MS media composition is the most widely 
used nutrient media in plant tissue cultures.
Chapter 7_Plant Tissue Culture.indd   168 23-01-2025   11:23:56
Reprint 2025-26
Plant Tissue Culture
169
Box 1
Major landmark discoveries in plant tissue culture and its applications
1902
Gottlieb Haberlandt proposed that plant cells can be cultured on arti??cial 
media and developed the concept of in vitro cell culture.
1904
Hanning initiated work on excised embryo culture and later cultured 
embryos from several cruciferous species.
1922
Kotte and Robbins suggested root and stem tips as possible explants to 
initiate in vitro tissue culture.
1926 Went discovered the ??rst plant growth hormone, i.e., Indole Acetic Acid (IAA).
1934
The role of vitamin B as growth supplement in plant tissue culture was 
reported by White. He could successfully establish continuous growing 
cultures from tomato root tips.
1937 White formulated the ??rst synthetic plant tissue culture medium (WM).
1941
Johannes Van Overbeek introduced coconut water as a media component 
and demonstrated its bene??cial effects on in vitro tissue culture.
1946 Ball raised whole plants from shoot tips of Lupinus.
1954 Muir successfully induced cell division in mechanically isolated single cells.
1955
Skoog and Miller reported the discovery of Kinetin, which is a type of 
cytokinin and promotes cell division.
1957
Skoog and Miller described chemical control hypothesis of root and shoot 
differentiation by manipulating the ratio of concentrations of auxin and 
kinetin.
1962
Murashige and Skoog formulated MS medium with higher salt 
concentrations.
1964
Guha and Maheshwari produced the ??rst androgenic haploid Datura plant 
by anther culture.
1971
Protoplasts were subcultured in vitro, and plants were regenerated from 
their culture.
1972
Protoplast from two different species of Nicotiana were isolated, fused 
together and somatic hybrids were generated successfully.
1976
Gynogenic haploid plants were successfully cultured from unfertilised 
ovaries of barley by San Noeum.
1978
Melchers and colleagues produced ‘Pomato’, which was a hybrid of potato 
and tomato, and was produced through somatic hybridisation. 
Chapter 7_Plant Tissue Culture.indd   169 23-01-2025   11:23:56
Reprint 2025-26
Biotechnology XII 170
1981
The term ‘Somaclonal Variations’ was introduced by Larkin and Scowcroft, 
for the genetic variations introduced during the plant tissue culture. 
Horsh and colleagues produced transgenic tobacco plants. Leaf discs were 
used as explants and were cultured with Agrobacterium tumefaciens.
Klien and colleagues developed high-velocity microprojectile-based DNA 
delivery ‘biolistic gene transfer’ method for plant transformation.
1987
Y. Fujita and Mamoru Tabata established Lithospermum erythrorhizon cell 
cultures for the shikonin production and commercialised it.
Transgenic Bt-cotton was produced by Monsanto and in 2000, it was 
approved by the Government of India for commercial production in India.
1993 Kranz and Lorz produced fertile maize plants through in vitro fertilisation.
Plant tissue culture free plant transformation method ‘Arabidopsis 
Floral-dip’ was developed.
Transgenic rice engineered for the production of provitamin A (beta-carotene) 
in rice endosperm was developed and is called ‘Golden Rice’. 
The ??rst plant produced enzyme was approved for human use. It is used to 
treat a rare lysosomal storage disease called Gaucher’s Disease. 
Somatic embryogenesis was introduced in plant transformation through the 
embryonic genes. 
7.2 Plant c ell and t issue c ulture t ec Hniques Virtually any part of the plant like leaf, apical meristem, 
embryo, cotyledon, hypocotyl, etc., can be used as a 
starting material called explant. These explants are 
transferred on to the nutrient media and whole plants 
can be regenerated through in vitro culture. It has been 
observed in various research experiments that different 
plant organs of different plant species respond in 
different ways as per their nutritional requirement and 
physical conditions under in vitro culture conditions. 
However, the response of different plant organs varies 
for in vitro culture. For example, immature embryos 
are more responsive than apical meristem, which are 
generally more responsive than leaf explants on a 
particular tissue culture media and culture conditions. 
Chapter 7_Plant Tissue Culture.indd   170 23-01-2025   11:23:56
Reprint 2025-26
Page 5


Plant tissue culture (PTC) refers to the cultivation of 
undifferentiated plant cells, tissues or organs on synthetic 
media under aseptic environment and suitable controlled 
physical conditions. It is an important tool for both basic 
research as well as commercial applications. Plant tissue 
culture is based upon the unique characteristic of a plant  
cell, i.e., totipotency. Totipotency is the ability of a vegetative 
cell to divide and differentiate into any type of specialised 
cell or to regenerate into a whole plant.
7.1 Historical Pers Pective In 19
th
 century, German scientists Theodor Schwann 
and Matthias Schleiden, drew attention to the fact that a 
cell is the basic unit of life and has the capacity to divide 
and grow. During 1890’s, Gottlieb Haberlandt (German 
Botanist), pioneered the ??eld of PTC with his idea to achieve 
continuous cell divisions in plant cells on nutrient media. 
He attempted to culture fully differentiated plant cells on 
simple nutrient media. He laid down several principles of 
plant tissue culture in 1902, like plant cells are capable 
of resuming uninterrupted growth, or it is possible to 
7.1 Historical 
Perspective
7.2 Cell and Tissue 
Culture Techniques
7.3 Nutrient Media
7.4 Culture Types
7.5 Applications of 
Plant Cell and 
Tissue Culture  
Plant Tissue Culture
7
Chapter 
Chapter 7_Plant Tissue Culture.indd   167 23-01-2025   11:23:56
Reprint 2025-26
Biotechnology XII 168
regenerate embryos from vegetative cells. Later, all of the 
predictions made by him were found to be true as they 
were con??rmed experimentally by other researchers. This 
is the reason he is regarded as the ‘Father of Plant Tissue 
Culture’. 
During 1902–1930s, several attempts were made 
to culture the isolated plant tissues, like root or shoot 
tips, and continuously growing plant cell cultures were 
established. The discovery that vitamins and natural 
auxins are necessary for the growth of plant tissues on 
synthetic media gave a signi??cant boost to PTC. During 
1940s –70s, extensive studies were performed to improve 
the existing techniques for developing new methods to 
optimise the nutrient media components for culturing 
plant tissues. Coconut water stimulated the development 
of young embryos and was used with nutrient media for 
in vitro cultures. Later, other natural supplements, like 
corn milk, orange juice, etc., were used for developing 
callus culture of several species, like woody plants and 
herbaceous dicot plants. During 1950s, adenine, kinetin 
and high levels of phosphate were used in nutrient media 
that resulted in the successful initiation of cultures 
from non-meristematic tissues and production of shoots 
or roots. It was also established during this time that the 
morphogenic fate of cultured cells was directly in??uenced 
by the exogenous balance of auxins and kinetin. It was 
suggested that a relatively high level of auxin to kinetin 
causes rooting, while the reverse led to shooting and 
intermediate levels were responsible for the proliferation of 
callus. This led to the regeneration of new plants through 
tissue culture using various plant tissues or organs as 
starting material in several commercial applications. An 
arti??cial culture medium developed by Murashige and 
Skoog (MS) was successful for culturing plants and resulted 
in the initiation of tissue culture from a large number of 
plant species. MS media composition is the most widely 
used nutrient media in plant tissue cultures.
Chapter 7_Plant Tissue Culture.indd   168 23-01-2025   11:23:56
Reprint 2025-26
Plant Tissue Culture
169
Box 1
Major landmark discoveries in plant tissue culture and its applications
1902
Gottlieb Haberlandt proposed that plant cells can be cultured on arti??cial 
media and developed the concept of in vitro cell culture.
1904
Hanning initiated work on excised embryo culture and later cultured 
embryos from several cruciferous species.
1922
Kotte and Robbins suggested root and stem tips as possible explants to 
initiate in vitro tissue culture.
1926 Went discovered the ??rst plant growth hormone, i.e., Indole Acetic Acid (IAA).
1934
The role of vitamin B as growth supplement in plant tissue culture was 
reported by White. He could successfully establish continuous growing 
cultures from tomato root tips.
1937 White formulated the ??rst synthetic plant tissue culture medium (WM).
1941
Johannes Van Overbeek introduced coconut water as a media component 
and demonstrated its bene??cial effects on in vitro tissue culture.
1946 Ball raised whole plants from shoot tips of Lupinus.
1954 Muir successfully induced cell division in mechanically isolated single cells.
1955
Skoog and Miller reported the discovery of Kinetin, which is a type of 
cytokinin and promotes cell division.
1957
Skoog and Miller described chemical control hypothesis of root and shoot 
differentiation by manipulating the ratio of concentrations of auxin and 
kinetin.
1962
Murashige and Skoog formulated MS medium with higher salt 
concentrations.
1964
Guha and Maheshwari produced the ??rst androgenic haploid Datura plant 
by anther culture.
1971
Protoplasts were subcultured in vitro, and plants were regenerated from 
their culture.
1972
Protoplast from two different species of Nicotiana were isolated, fused 
together and somatic hybrids were generated successfully.
1976
Gynogenic haploid plants were successfully cultured from unfertilised 
ovaries of barley by San Noeum.
1978
Melchers and colleagues produced ‘Pomato’, which was a hybrid of potato 
and tomato, and was produced through somatic hybridisation. 
Chapter 7_Plant Tissue Culture.indd   169 23-01-2025   11:23:56
Reprint 2025-26
Biotechnology XII 170
1981
The term ‘Somaclonal Variations’ was introduced by Larkin and Scowcroft, 
for the genetic variations introduced during the plant tissue culture. 
Horsh and colleagues produced transgenic tobacco plants. Leaf discs were 
used as explants and were cultured with Agrobacterium tumefaciens.
Klien and colleagues developed high-velocity microprojectile-based DNA 
delivery ‘biolistic gene transfer’ method for plant transformation.
1987
Y. Fujita and Mamoru Tabata established Lithospermum erythrorhizon cell 
cultures for the shikonin production and commercialised it.
Transgenic Bt-cotton was produced by Monsanto and in 2000, it was 
approved by the Government of India for commercial production in India.
1993 Kranz and Lorz produced fertile maize plants through in vitro fertilisation.
Plant tissue culture free plant transformation method ‘Arabidopsis 
Floral-dip’ was developed.
Transgenic rice engineered for the production of provitamin A (beta-carotene) 
in rice endosperm was developed and is called ‘Golden Rice’. 
The ??rst plant produced enzyme was approved for human use. It is used to 
treat a rare lysosomal storage disease called Gaucher’s Disease. 
Somatic embryogenesis was introduced in plant transformation through the 
embryonic genes. 
7.2 Plant c ell and t issue c ulture t ec Hniques Virtually any part of the plant like leaf, apical meristem, 
embryo, cotyledon, hypocotyl, etc., can be used as a 
starting material called explant. These explants are 
transferred on to the nutrient media and whole plants 
can be regenerated through in vitro culture. It has been 
observed in various research experiments that different 
plant organs of different plant species respond in 
different ways as per their nutritional requirement and 
physical conditions under in vitro culture conditions. 
However, the response of different plant organs varies 
for in vitro culture. For example, immature embryos 
are more responsive than apical meristem, which are 
generally more responsive than leaf explants on a 
particular tissue culture media and culture conditions. 
Chapter 7_Plant Tissue Culture.indd   170 23-01-2025   11:23:56
Reprint 2025-26
Plant Tissue Culture
171
Plant regeneration in cultures can mostly be achieved 
by two morphogenetic pathways—organogenesis and 
somatic embryogenesis. Inducing  the formation of various 
vegetative organs from cells or tissues in plant tissue 
culture is called organogenesis. First, the specialised 
cells of explants start dividing under certain speci??c 
conditions and form a mass of undifferentiated cells. 
This process is called dedifferentiation. This is followed 
by the formation of organ primordia, like shoot or root, 
and is called redifferentiation. Relative concentration of 
growth hormones (especially auxins and cytokinins) play 
an important role in organogenesis.
The process of formation of an embryo from somatic 
cells is called somatic embryogenesis. Resulting embryos 
are called somatic embryos. Somatic embryogenesis follows 
embryogenic pathways of zygotic embryogenesis. Somatic 
embryos are very similar to zygotic embryos, except in their 
place of origin and being larger in size.
Following is the step-by-step procedure that explains 
the in vitro plant tissue cultures using tomato cotyledons 
as explants (Fig. 7.1).
Some of the basic requirements for plant tissue culture are: 
(i) Washing area—the place to wash glassware, 
plasticware and other labware used in PTC. Washed 
labware need to be stored at a clean and dry place.
(ii) Various media components for the preparation of 
Nutrient Media.
(iii) Facility to sterilise nutrient media and store media 
at low temperatures.
(iv) Facilities for maintenance of cultured tissues in 
aseptic conditions under controlled environment, 
i.e., light, temperature and humidity.
Steps of plant tissue culture
 (i) Selection of a suitable nutrient media and its 
sterilisation by autoclaving or passing through 
micropore ??lters to avoid microbial contamination. 
 (ii) Selection of a starting desired material for tissue 
culture, i.e., explants. Any plant tissue , organ 
or part, which is used in plant tissue culture to 
regenerate mass of dedifferentiated cells, tissues, 
organ or whole plant, is called explant. Most 
Chapter 7_Plant Tissue Culture.indd   171 23-01-2025   11:23:56
Reprint 2025-26