Plant Tissue Culture Terminology PDF

# An Introduction to Plant Tissue Culture ## Plant Tissue Culture Terminology * **Adventitious:** Development of shoots, roots, or any other organs from unusual points of origin. In plant tissue culture, shoots or roots are developed from callus tissue and embryos from sources other than zygote. *...

# An Introduction to Plant Tissue Culture ## Plant Tissue Culture Terminology * **Adventitious:** Development of shoots, roots, or any other organs from unusual points of origin. In plant tissue culture, shoots or roots are developed from callus tissue and embryos from sources other than zygote. * **Adventive Embryony:** Embryo formation and development resulting from asexual cells, as occurs in certain members of Rutaceae. * **Androgenesis:** Development of a plant in vitro from a male gametophyte. * **Apical Meristem:** A small group of meristematic cells located at the tips of the shoot and root axis, which are the progenitors of these structures.. * **Aseptic Culture:** A culture without undesired or foreign life forms. An aseptic culture means the purposeful culture of different types of cells, tissues of higher plants without any contamination of bacteria, fungi, etc. * **Aseptic Technique:** Techniques used to prevent the entry of fungi, bacteria or other micro-organisms into cell, tissue, and organ cultures. * **Auxins:** A group of growth substances produced in the zone of elongation that cause cell elongation, apical dominance, root initiation, etc. Examples include: * **2, 4-D (2, 4-dichlorophenoxyacetic acid)** * **IAA (Indole-3-acetic acid)** * **o-naphthaleneacetic acid (NAA)** * **Indole butyric acid (IBA)** * **IBA (synthetic auxins commonly used in plant tissue culture)** * **Batch Culture:** A type of cell suspension culture in which cells or small cell aggregates grow in a definite volume of nutrient medium. * **Callus Tissue:** An unorganized mass of proliferative cells produced either in culture or in nature. * **Cell Culture:** Term used to define the maintenance or culture of cells in vitro, including the culture of single cells. In cell cultures, the cells are no longer organized into tissues. * **Chemostat:** A type of cell suspension culture in which growth rate and cell density remain constant by a fixed rate of input of growth-limiting nutrients. * **Chimera:** An organism or tissue that is not genetically homogeneous. * **Clonal Propagation:** In vitro propagation of plants that are considered to be genetically uniform and originated from a single individual or explant. * **Clone:** A group of genetically identical individuals produced from a single explant. * **Cybrid:** When two or more protoplasts fuse, then their cytoplasms always fuse, but the nuclei may or may not fuse. If, in a binucleate heterokaryon, one of the nuclei disappears, then it is called a cybrid or a cytoplasmic hybrid as the cytoplasms remain in a fused state. * **Cytodifferentiation:** Means the in vitro vascular differentiation, particularly the xylem elements within the callus tissue. * **Cytokinins:** A group of growth hormones which stimulates cells to divide, although in some cases they affect only cell enlargement. Another more spectacular property of cytokinins is their ability to induce the formation of organs by undifferentiated callus tissue. * **Differentiation:** Process of change in a cell, tissue, or organ resulting in the variety of structure and function found in the adult or other phases in the life history. * **Disease Free:** A plant certified through specific pathological tests as being free of pathogens or infectious micro-organisms. * **Embryo Culture:** In vitro culture of isolated zygotic mature or immature embryos. * **Embryogenesis:** The development of embryoids in plant tissue culture. * **Embryoid:** A structure comparable to the zygotic embryo which is produced in tissue culture by dividing somatic cells. * **Epigenetic Variation or Change:** Phenotypic variation or change which has a non-genetic basis. Epigenetic changes are not transmitted by sexual reproduction. * **Explant:** The piece of tissue isolated from the intact plant that is used to initiate the culture. * **Friable or Friability:** The tendency of plant cells, or cells of callus tissue, to separate from one another. * **Gene Bank:** A store of germplasm. * **Genetic Change:** Phenotypic variation or change which has a genetic basis. Genetic changes are transmitted by sexual reproduction. * **Germplasm:** Gene combinations available for breeding. * **Habituated:** It is the ability of culture tissue or organ to grow on nutrient medium without added plant hormones. * **Haploid:** A cell or nucleus containing a single set of chromosomes. * **Heterokaryon:** A cell in which two or more genetically unlike nuclei are present. * **Heterozygous:** A term applied to an organism that possesses two different alleles for a trait. * **Homozygous:** A term applied to an organism that has two identical alleles for a particular trait. * **In Vitro:** Cells and tissues removed from the intact organism and placed in an artificial situation for experimentation. Literally it means "in glass". * **In Vitro Propagation:** Propagation of plants in artificial nutrient medium under controlled conditions. * **In Vivo:** Cell and tissue when they remain integrated into the whole plant. Literally it means "in life". * **Inoculum:** A portion or volume or aliquot of suspension culture used for its subculture. * **Meristemoid:** A localized group of meristematic cells appeared within the callus tissue during culture and such cells may give rise to roots and/or shoots. * **Micropropagation:** The asexual or vegetative propagation of whole plants using tissue culture techniques. * **Morphogenesis:** The process of growth and development of a form or structure. * **Nutrient Medium:** A nutritive solution for culturing cells and tissue. It is prepared by mixing several inorganic and organic chemicals, a carbohydrate, vitamins, amino acids, and phytohormones. Nutrient medium is solidified by adding a definite amount of agar-agar. * **Nurse Culture:** An isolated cell which generally fails to divide when plated directly on the medium used for callus cultures is able to divide under the nursing effect of the callus. * **Organ Culture:** The maintenance or growth of organ primordia in vitro without forming callus tissue. * **Organogenesis:** The development of organs or primordia from undifferentiated cell masses in tissue culture. * **Passage:** The transfer of cell or tissue from old culture medium to fresh culture medium within a definite time period. Maintenance of culture in a medium for a definite period before transferring to fresh medium constitute a passage. This term is synonymous with the term "subculture". * **Plantlet:** The small regenerated plant while it is still within the culture tube or flask. * **Plant Tissue Culture:** It's an experimental technique for culturing plant protoplast, cell, tissue and organ in artificial nutrient medium under aseptic and controlled conditions. * **Plating Efficiency:** A quantitative assessment of the percentage of cell colonies per total number of cells or protoplasts plated at a definite density for a specific time period. It can be determined by counting cell colonies under a microscope at the end of the experiment and calculated by using the formula: ``` Plating efficiency-(PE)= No. of Colonies/plate No. of cell units × 100 ``` * **Primary Culture:** A culture started from explants taken directly from plant body. * **Primordium:** Earliest stage in the development of a plant organ. * **Protoplast:** The entire plant cell without its cellulosic cell wall. * **Protoplast Fusion:** A technique in which two or more protoplasts are fused into a single cell. * **Somaclonal Variation:** It's the genetic variability which is generated during tissue culture. * **Somatic Hybridization:** The in vitro fusion of plant protoplasts derived from somatic cells which differ genetically. * **Sterile:** To make free from microorganisms. * **Sub Culture:** See 'Passage'. * **Suspension Culture:** Cell or cell aggregates cultured in moving liquid medium. * **Totipotency:** Totipotency is the genetic potential of a plant cell to produce the entire plant. * **Transfection:** In culture, the transfer of naked, foreign DNA into cells for the purpose of genomic integration. * **Transgenesis:** In plant cell culture, the introduction and stable genomic integration of foreign DNA into a plant cell by any means, resulting in a genetic modification. * **Virus-Free:** A plant certified through specified tests as being free of specified plant viruses.