Plant Tissue Culture and Micropropagation

Plant hybridization often involves emasculation (removing anthers to prevent self-pollination) and pollination. Cybridisation is a separate technique involving protoplast fusion.

The capacity to generate a whole new plant from any cell is called totipotency. That whole plant could be regenerated from explants ( any part of plant that taken out and grown under sterile conditions in a special nutritive media). 

Micropropagation is the tissue culture technique used for rapid vegetative multiplication of ornamental plants and fruit trees by using small sized explants.

Shoot tips are used to generate disease-free plants because the meristematic region is typically free of viruses, even if the rest of the plant is infected.

An explant is a part of the plant that taken out and grown in special nutritive media under sterile conditions. This is the process to generate a whole plant in tissue culture.

The correct answer is mutation breeding:

Micropropagation is culture of apical shoots, axillary buds and meristems on suitable nutrient medium to produce a genetically identical progeny. Macropropagation is production of progeny by means of conventional techniques including cuttings, air-layering and grafting. Production of genetically identical cell lineage or organisms is called as cloning. It includes both conventional and tissues culture techniques. Asexual propagation refers to production of progeny by single parent plant, it can occur through vegetative propagules (rhizome, tubers and bulb) or by artificial methods (cutting, and grafting).

A callus is an unorganized mass of proliferating parenchyma cells that develops from an explant in culture media.

Plant callus is a mass of unorganized cells derived from plant tissue for use in biological research and biotechnology. In plant biology, callus cells are those cells that cover a plant wound. Callus formation is induced from plant tissues after surface sterilization and plating onto in vitro tissue culture medium. Plant growth regulators, such as auxins, cytokinins and gibberellins are supplemented into the medium to initiate callus formation or somatic embryogenesis.

Explant is any portion taken from a plant that will be used to initiate a culture. It can be a portion of the shoot or of the leaves or even just some cells. It is a piece of sterile plant tissue to be used for tissue culture under aseptic conditions. Inoculant is the active material used in an inoculation. Clones are organisms that are exact genetic copies. Somacloning is cloning of plant with a single cell. 

Philip White, R.J. Gautheret, and P. Nobecourt are all pioneers who independently and successfully established callus cultures in the 1930s.

In vitro refers to experiments performed in a controlled environment outside a living organism, such as in a test tube or petri dish.

• Totipotency is the ability of a single cell to divide and produce all of the differentiated cells in an organism. 
  
• For example, Spores and zygotes are examples of totipotent cells.
• Hence a plant cell has the potential to develop into a full plant. The property is called Totipotency.
• So, the correct answer is 'Totipotency'.

• Cellular totipotency is the ability of a single cell to produce all cell types and to organize them into an entire organism when cultured in a suitable culture medium at an appropriate temperature and aeration conditions. For example, Spores and zygote are examples of the totipotent cell.
  
• The concept of totipotency was established by a German Botanist, Professor Gottlieb Haberlandt in 1902 in the plant body. He stated that every living cell of the plant body able to regenerate the whole plant body because it is derived from the fertilized egg and contain hereditary information.
• Hence concept of cellular totipotency was established by Haberlandt.
• So, the correct answer is 'Haberlandt'.

Philip White is credited with the first successful continuous culture of tomato roots in 1934, though some sources cite 1932 for his early work on root tips.

Gottlieb Haberlandt, often called the father of plant tissue culture, proposed the concept of cellular totipotency in 1902.

F.C. Steward and his colleagues famously demonstrated cellular totipotency using carrot phloem cells in the 1950s.

Tissue culture is a biological technique which involves the development of the plant by the totipotent cells under the controlled condition on a nutrient culture medium of the known composition. The totipotent cells are taken from the active part of the plant like root, stem leaf, pollen etc. The plant part which is used for the culture is known as explant. 

Callus is unorganized actively dividing mass of cells maintained in culture. It has meristematic cell which has ample amount of cytoplasm to trigger cell division. It is an undifferentiated mass of cell which differentiates when treated with the growth hormones to promote cell division, differentiation and morphogenesis. It heals the injury in the cell as callus has meristematic cell which replaces the worn out and damaged cell by rapid cell division and it can also replace damage tissue developed in the region of wound.

Totipotency is the ability of the plant to generate new cell by cell division. A cell from leaf is made to grow into complete plant under culture conditions. The cell of the leaf used for the culture is taken from the tip of the leaf and it has ample amount of meristematic cell. The meristematic cell of the leaf is grown on a cultured media it develops into a undifferentiated mass of callus. The cells of callus have active nucleus and cytoplasm so they are totipotent. The totipotent cells of callus differentiate on treating with growth hormone. Callus when treated with auxin it promotes rooting and when it is treated with cytokinin it stimulates cell maturation, differentiation and finally, promotes the development of stem. 

F.C. Steward is associated with tissue culture and played an important role in developing the techniques. Caplin and Steward were the first one to use coconut water as a plant growth regulator in the nutrient media. Later on, it was considered as a substitute for cytokinin. He was also involved in the somatic embryogenesis in carrot cell suspension cultures and production of complete plants. He also laid the foundation of micropropagation technique.

An explant is any part of a plant (tissue, organ, or cell) that is excised and placed into a culture medium for tissue culture.

Axenic culture refers to a culture that is free from any other living organisms, meaning it is a pure culture.

Callus is a growing mass of unorganized plant parenchyma cells. It is mainly  used in plant tissue culture. So basically in other words, callus is a undifferentiated mass of tissue. 

• The process by which thousands of plants can be raised within limited time and space is Tissue culture.
  
• When new plants are grown from a small piece of plant tissue or cells removed from the growing tips of a plant in a suitable growth medium is called tissue culture.
  
• Its advantages are:-

Meristem is free from viruses and they are used to grow virus-free plant cultures. The meristem has the ability of rapid rate of mitotic cell division, which is much more than the viral rate of division. Hence, the virus is unable to spread through them, hence the meristems are almost always free of viruses.

Tissue culture is the growth of tissues or cells in an artificial medium separate from the organism. Plant parts can be sterilized by using several disinfecting agents i.e., use of chemicals.

• In sexual reproduction, two offsprings have the same genetic material and the same body features are called identical twins.
• They are two offspring produced by the same pregnancy.
• Twins have the same genetic material and the same body features because they develop from a single fertilized egg, they have the same genome.
• So, the correct answer is 'Twins'.

In plant tissue culture, an explant is the initial plant tissue piece that is introduced into the culture medium. This explant will then proliferate, differentiate, and regenerate into whole plants through various tissue culture techniques like organogenesis or somatic embryogenesis.

Tissue culture is a collection of techniques used to grow cells, tissues or organs under sterile conditions on a nutrient culture medium of known composition ( in vitro). The emergence of this technique became a turning point when polio virus, could be cultivated in vitro, a discovery of Enders, Weller, and Robbins (1949). This led to the feasibility of quantitative metabolic studies in animal viruses. Tissue culture is, therefore, today a vital part of life science research ( across plants and animals ) and in every area of research that includes bacteriology, embryology and virology.

• The callus is an unspecialized, unorganized, growing and dividing the mass of cells.
• It produced when explants are cultured on the appropriate solid medium, with both auxin and cytokinin in correct conditions.
  
• In Callus culture, Auxins increase root growth and cytokinins increase shoot growth.
• Hence Cytokinin increase shoot growth in callus culture.
• So, the correct answer is 'Cytokinin'.

Plant cells are totipotent. Hence, plant cells can be cultured to grow entire plants. In-plant tissue culture, a small meristematic tissue called explant is used to generate a mass of undifferentiated cells called callus. Entire plantlets can be generated from callus by applying a carefully balanced ratio of phytohormones.

totipotency is the ability of a plant to use all its genes and form a new plant. to prove this F.C Steward did an experiment on the root cells of the carrot plant with which he produced a whole new carrot plant.

The potential of the somatic cell to grow and develop into a multicellular and multi-organed organism through the technique of cloning is referred to as cellular totipotency. While German botanist Gottleib Haberlandt introduced the concept of in vitro cell culture, Prof. F.C. Steward of Cornell University worked to show that cellular totipotency is an inherent capability of every single cell. Thus, the correct answer is option A.

Totipotency is the ability of a single cell to divide and produce all of the differentiated cells in an organism. Spores and zygotes are examples of totipotent cells. In the spectrum of cell potency, totipotency represents the cell with the greatest differentiation potential. Many somatic plant cells, including some fully differentiated types (e.g., leaf mesophyll), provided they contain intact nuclear, plastid and mitochondrial genomes, have the capacity to regenerate into whole plants. 

Somaclonal variation is the variation seen in plants that have been produced by plant tissue culture. Chromosomal rearrangements are an important source of this variation. The term somaclonal variation is a phenomenon of broad taxonomic occurrence, reported for species of different ploidy levels and for outcrossing and inbreeding, vegetatively and seed propagated and cultivated and non-cultivated plants. Characters affected include both, qualitative and quantitative traits. Somaclonal variation is seen in tissue culture grown plants.
Somaclonal variation is not restricted to, but is particularly common in, plants regenerated from callus. The variations can be genotypic or phenotypic, which in the latter case can be either genetic or epigenetic in origin.
Typical genetic alterations are: changes in chromosome numbers (polyploidy and aneuploidy), chromosome structure (translocations, deletions, insertions and duplications) and DNA sequence (base mutations). A typical epigenetics-related event would be gene methylation.

Explant is any portion taken from a plant that will be used to initiate a culture. It can be a portion of the shoot or of the leaves or even just some cells. Thus, the correct answer is option C. 

Totipotency is the ability of a single cell to divide and produce all of the differentiated cells in an organism. Many somatic plant cells, including some fully differentiated types (e.g., leaf mesophyll), provided they contain intact nuclear, plastid and mitochondrial genomes, have the capacity to regenerate into whole plants. This phenomenon is totipotency.

Explant culture is a technique used for the isolation of cells from a piece or pieces of tissue. Tissue harvested in this manner is called as an explant. It can be a portion of the shoot, leaves or some cells from a plant or can be any part of the tissue from an animal or from umblical cord tissue. So, explant is small part of the plant meant for tissue culture and not uprooted for transplantation, plant, collected after harvesting or exploited part of a plant

Micropropagation is the practice of rapidly multiplying stock plant material to produce many progeny plants using modern plant tissue culture methods.

Micropropagation is the method of large production of plantlets in a less time. In this method, a small piece of plant tissue (explant) is cultured in a sterile medium which later develops into new plantlets. The offsprings produced by this methods are the exact copy of their parent plant. 

Micropropagation is the method of large production of plantlets in a less time. In this method, a small piece of plant tissue (explant) is cultured in a sterile medium which later develops into new plantlets. The offsprings produced by this methods are the exact copy of their parent plant and are known as somaclones. So, the technique of micropropagation is also known as cloning.

Micropropagation is a technique to obtain new plants by cultivating the cell or tissue in culture medium through tissue culture.

The tissue obtained from a plant to be cultured is called an explant.
Explants can be taken from different many parts of a plant, including
portions of shoots, leaves, stems, flowers, roots, single
undifferentiated cells and from many types of mature cells provided are
they still contain living cytoplasm and nuclei and are able
de-differentiate and resume cell division. This has given rise to the
concept of totipotentency of plant cells. So, the correct answer is 'Explants'.

In plant tissue culture, undifferentiated tissue is referred to as callus, although a callus can contain meristematic nodules that may not be obvious to the naked eye but which never develop further unless suitable conditions are supplied.

Tissue culture is a process that involves exposing plant tissue to a specific regimen of nutrients, hormones, and light under sterile, in vitro conditions to produce many new plants, each a clone of the original mother plant, over a very short period of time. The term plant tissue culture (micro propagation) is generally used for the aseptic culture of cells, tissues, organs and their components under defined chemical and physical conditions in vitro.

Micro-propagation means the propagation of plants by growing plantlets in tissue culture and then planting them out.

Tissue culture is a growth of cells or tissues separate from the organism in an artificial environment. The process is called as micropropagation in plant tissue culture. In tissue culture, the small piece of plant or animal is used to grow complete individual and those small parts are called as explants whereas complete grown individuals are called clones. The explant initially turns into rapidly dividing unorganised mass of cells on solid or liquid culture and that is called a callus. 

In 1902 C.Haberlant was the first attempted to culture isolated plant cells invitro on artificial medium. But the discovery of the use of auxin is done by three scientists Gautherel, Nobecourt, and White. This discovery is the second phase of plant tissue culture. Then White discovery's proves that plant could be successfully regenerated from undifferentiated tissue or even single cell in culture called tissue culture. Then tissue culture was developed by P R White in 1925.
So the correct option is C.

Steward et al. (1958) used phloem tissue from the secondary root of a carrot to demonstrate cellular totipotency.

Philip White is widely credited with the first successful long-term culture of isolated tomato roots in 1934.

Cellular totipotency means the ability of a cell to give rise to complete individual i.e., the formation of the complete cellular organisation from a single cell. Plant cells are totipotent as they can give rise to complete plant. So answer D is correct.

Tissue culture is a biological technique which involves the development of plant under the controlled condition on a nutrient culture medium of the known composition. The pant developed by the tissue culture are cloned by the process of micropropagation. Gottlieb Haberlandt was the first to attempt tissue culture. He was the first to point out the possibilities of the culture of isolated tissues. He is known as the father of tissue culture.

Callus is unorganized actively dividing the mass of cells maintained in culture. It has a meristematic cell which has ample amount of cytoplasm to trigger cell division. It is treated with the growth hormones to allow the cell division and differentiation. Callus when treated with auxin it promotes rooting and when it is treated with cytokinin it stimulates cell maturation, differentiation and finally, promotes the development of stem.

Panchanan Maheshwari was a world-renowned Indian botanist who made significant contributions to plant embryology and established the Department of Botany at the University of Delhi as a center for research.

Totipotency is the genetic potential of a plant cell to produce an entire plant. A single cell can produce all cell types and organises them into an entire organism.

Plant medium used widely in preparation of culture medium is obtained from the Cocos nucifera. It provides the growth hormone known as cytokinin. The first natural cytokinin known as zeatin was obtained from the coconut plant.

Tissue culture allows for the mass production of clones. In dioecious plants like papaya, it can be used to produce only female plants from selected high-yielding female parent tissue.

Callus is defined in plant tissue culture as an unorganized, proliferating mass of parenchyma cells that arises from an explant. It is typically maintained on a culture medium containing specific hormones.

White was the first one to successfully attempt the technique of tissue culture. He cultured tomato roots in a nutrient media composed of vitamins. He developed the continuously growing callus from the root which had the property of totipotency.

Banana is commercially and rapidly multiplied in vitro primarily through multiple shoot production, often initiated from shoot tip cultures. This method allows for the production of many genetically identical plantlets.

Gottlieb Haberlandt is widely recognized as the father of plant tissue culture. In 1902, he proposed the concept of cell totipotency and attempted to culture isolated plant cells.

Haploid plant cultures are primarily used for generating homozygous doubled haploids through chromosome doubling, which rapidly produces pure lines for breeding. Callus is formed from explants rather than being a specific use of haploids, and the other options do not relate to haploid utility.

Statements 1, 3, and 4 correctly define callus as a disorganised mass of cells, embryoid as an embryo-like structure formed in vitro, and explant as the excised plant tissue. Statement 2 is slightly imprecise or often excluded in specific code selections because totipotency refers to the genetic potential of a cell rather than just an organ.

A callus is an unorganized and undifferentiated mass of proliferating plant cells formed when an explant is cultured in vitro. Differentiated cells form specific tissues, while decaying cells refer to dead matter.

Electroporation is a technique used to introduce foreign DNA into cells by applying a high-voltage electrical pulse to create temporary pores in the cell membrane. It is a standard method in plant and animal tissue culture for transformation.

Somaclones are plants produced through tissue culture that exhibit genetic variation compared to the parent plant. This variation arises during the culture process.

A) Shoot tip culture may be described as the culture of terminal portion of a shoot comprising the meristem together with primordial and developing leaves and adjacent stem tissue. It is a common process used for micropropagation

Plant tissue culture is a collection of techniques used to maintain or grow plant cells, tissues or organs under sterile conditions on a nutrient culture medium of known composition. Plant tissue culture is widely used to produce clones of a plant in a method known as micropropagation. Agitation during tissue culture serves for:

• Aeration of the culture
• Constant Mixing
• Breakage of cell aggregates in small particles

• Tissue culture, also known as micropropagation, is a propagation method used to produce plants under sterile conditions. 
• This method uses plant explants (plant parts) or seeds that have been sterilized before being placed in containers with a growing medium (usually a gel) that has some nutrients added. 
• Micropropagation is the growing of plants from meristematic tissue or somatic cells of superior plants on nutrient suitable media under controlled aseptic physical conditions.

• Cells derived from a single cell through mitosis constitute a clone and the process of obtaining clones is called cloning (asexual progeny of a single individual make up a clone). 
• Plant tissue culture or micropropagation is the technique of maintaining and growing plant cells, tissues or organs especially on artificial medium in suitable containers under controlled environmental conditions.

• Micropropagation is a more recent practice for growing plants in a culture medium by providing them with all the necessary nutrients and inducing their growth artificially. So, statement A is correct.
• In the case of growth of plants through asexual means using tissue culture, first of all, the mass of cells is formed which is then differentiated into different cells and forms the entire plant body. This cell mass is called callus. So, statement B is also correct.
• Examples of micropropagation growth include orchids, dahlia, etc. So, the statement C is also correct.

Micropropagation is a tissue culture technique for plant propagation in which tissue is taken from a plant and grown in a laboratory to produce plants that are genetically identical to the parent. The small portion of plant tissue, sometimes only a single cell, is placed on a growth medium, typically containing sucrose as an energy source.