GLOSSARY – PLANT VARIETY RECKONER
GLOSSARY – PLANT VARIETY RECKONER
- Propagating material -Is defined as any plant or its component or part thereof including an intended seed or seed which is capable of or suitable for regeneration into a plant.
- Seed – is a type of living embryo or propagule capable of regeneration and giving rise to a plant which is true to such type.
- Essentially derived variety (EDV) – for a variety to be considered as essentially derived it must fulfill three requirements in relation to the initial variety.
- Predominant derivation from the initial variety while retaining the essential characteristics that result from the genotype or combination of genotypes of such initial variety.
- Clear Distinctiveness from the initial variety
- Conformity to the initial variety in the expression of the essential characteristics that result from the genotype or combination of genotypes of the initial variety.
- Conformity to the initial variety – has to be judged on a species by species basis. Methods of derivation may be used as a tool to help establish an essentially derived variety which can be decided only by scientifically reliable methods. Determining whether a plant variety is an essentially derived variety is mainly a question of whether it has been predominantly derived from a given variety or a product thereof.Somaclonal variations is not restricted to but is particularly common in plants re generated 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 (Ploidy), chromosome structure and DNA sequence
- Article 14 (5) ( c ) UPOV convention – deals with the concept of essentially derived varieties and reads as : ‘Essentially derived variety may be obtained for example by the selection of a natural or induced mutant or of a somaclonal variant.The selection of a variant is individual from plants of the initial variety, back crossing or transformations by genetic engineering.
- Somaclonal-Is the variation seen in plants that have being produced by plant tissue culture. Benefit is plant/ crop variation.
Chromosomal rearrangements are an important source of the this variation. Somaclonal variation in not restricted to but is particularly common in plants regenerated from Callus.
Somaclonal variation is not restricted to but is particularly common in plants regenerated from callus. The vaaritations can be genotypic or phenotypic, which in the later case can be either genetic or epigenetic in origin. Typical genetic alterations are changes in chromosome numbers (ploidy), chromosome structure and DNA sequence.
- Callus- Plant callus is growing mass of unorganized Plant Parenchyma cells. In living plants, callus cells are those cells that cover a plant wound.
- Genotype – is the part of the genetic makeup of a cell and therefore of any individual which determines one of its characteristics.
- Phenotype – of an organism is the composite of the organism’s observable characteristics traits including its morphology or physical form and structure, developmental process, its biochemical and physiological properties, behavior and products of behavior.
Eg : different variations on a sea shell
- Ploidy levels: There are two ploidy levels –
(1) PolyPloidy – state of cell or organism having more than two paired (homologous) sets of chromosome. Most species are diploid, meaning they have two sets of chromosome.
Eg: Triploid, tetraploid etc.
(2) Aneuploid – is the presence of an abnormal numbered of chromosome in a cell.
Eg : a human cell having 45 or 47 chromosome instead of the usual 46
- Epigenetics – is the study of heritable phenotype changes that do not involve alterations in the DNA sequence. The Greek prefix “EPI” in epigenetics implies features that “are on top of’ or ‘in addition to the traditional genetic basis for inheritance.
- Morphogenic – morphogenesis is the biological process that causes an organism to develop its shape. It is one of the 3 fundamental aspects of developmental biology along with the control of cell growth and cellular differentiation.
- Classical breeding : techniques such as crossing and selecting from the progeny cannot be considered as within the ambit of essentially derived variety.
- Backcross Breeding : is an effective method to transfer one or a few genes controlling a specific treat from one line into a second, usually elite breeding line. The parent with the desired trait called the donor parent, provides the desired trait and may not perform as well as elite variety in other verities .
- Transgenic Plants – are plants into which one or more genes from another species have been introduced into the genome, using genetic engineering Transgenic Plants are genetically engineered with new characteristics known as GMO.First Transgenic plant – Tobacco
First GMO Plant – Flavr Savr tomato
- Terminator and Verminator Technologies – Terminator Technology produces sterile seeds and verminator technology ensures that growers have to use particular proprietary chemicals.
Working of terminator Technology :
- Scientists at Terminator genes to a crop.
- The seed company initiates the Terminator process before sellingthe seeds by adding an inducer.
- Farmers plant seeds, grow plants and harvest mature but sterile seeds.
Eukaryote – A Eukaryote is an organism whose cell contains a nucleus within a membrane. Most living things are eukaryote made up of cells with distinct nuclei and chromosomes that contain their DNA. Eg.
- Prokaryotes: are one celled organisms that do not have a nucleus or any other membrane – Bound organelles inside them. The only organelles or internal structures that exist in prokaryotes are ribosomes which make portions needed by the organisms. Eg: Bactria
- In Situ – Conditions were genetic resources exists within eco systems and natural habitats and in the case of domesticated or cultivated species, in the surrounding were they have developed their distinctive properties.
- Ex Situ -Conditions were genetic resources exist outside their natural habitats such as botanic gardens, zoological garners and gene banks.
History has been a witness to farmers playing the crucial roles of being plant breeders, seed technologist, crop managers and harbingers of traditional knowledge which Was a natural out come of The deep association between man and nature.
Given, this nexus between man and nature, even the poorest of farmers had a deep understanding of farming crop – management, crop rotation, seed selection and soil treatments.
This knowledge gained through intense activities Pertaining to agriculture over many years Led to a robust know how or knowledge bank of plant diversity. Through trial and error and then simply by selecting best plants from their fields and protecting best quality seeds farmers were able to bring about the best variety of plants as per climatic conditions.