`color{Brown}"Micropropagation:"`
● As traditional breeding techniques `color{Violet}"failed to keep pace"` with demand and to provide sufficiently `color{Violet}"fast and efficient systems"` for crop improvement, another technology called tissue culture got developed.
● It was learnt by scientists, during `color{Violet}"1950s"`, that whole plants could be `color{Violet}"regenerated from explants"`, i.e., any part of a plant taken out and grown in a test tube, under `color{Violet}"sterile conditions"` in special nutrient media.
● This capacity to generate a `color{Violet}"whole plant"` from any cell/explant is called `color{Brown}"totipotency"`.
● It is important to stress here that the `color{Violet}"nutrient medium"` must provide a `color{Violet}"carbon source"` such as sucrose and also `color{Violet}"inorganic salts"`, vitamins, amino acids and `color{Violet}"growth regulators"` like auxins, cytokinins etc.
● By application of these methods it is possible to `color{Violet}"achieve propagation"` of a large number of plants in very `color{Violet}"short durations"`.
● This method of producing `color{Violet}"thousands of plants"` through tissue culture is called `color{Brown}"micropropagation"`.
● Each of these plants will be `color{Violet}"genetically identical"` to the original plant from which they were grown, i.e., they are `color{Brown}"somaclones"`.
● Many important food plants like `color{Violet}"tomato, banana, apple"`, etc., have been produced on commercial scale using this method.
`color{Brown}"Recovery of"` `color{Brown}"healthy plants"` `color{Brown}"from diseased plants:"`
● Another important application of the method is the `color{Violet}"recovery of healthy plants"` from diseased plants.
● Although the plant is `color{Violet}"infected with a virus"`, the `color{Brown}"meristem"` (apical and axillary) is `color{Violet}"free"` of virus.
● Hence, one can remove the meristem and `color{Violet}"grow it in vitro"` to obtain `color{Violet}"virus-free plants"`.
● Scientists have succeeded in `color{Violet}"culturing meristems"` of banana, sugarcane, potato, etc.
`color{Brown}"Somatic Hybridisation:"`
● Scientists have even `color{Violet}"isolated single cells"` from plants and after digesting their cell walls have been able to isolate `color{Violet}"naked protoplasts"` (surrounded by plasma membranes).
● `color{Violet}"Isolated protoplasts"` from two different varieties of plants – each having a `color{Violet}"desirable character"` – can be `color{Violet}"fused"` to get `color{Violet}"hybrid protoplasts"`, which can be further grown to form a new plant.
● These hybrids are called `color{brown}"somatic hybrids"` while the process is called `color{Brown}"somatic hybridisation"`.
● A `color{Violet}"protoplast of tomato"` has been fused with that of `color{Violet}"potato"`, and then they are grown – to form new `color{Violet}"hybrid plants"` combining tomato and potato characteristics- resulting in formation of tomato
● Unfortunately this plant `color{Violet}"did not have"` all the `color{Violet}"desired combination"` of characteristics for its commercial utilisation.
`color{Brown}"Micropropagation:"`
● As traditional breeding techniques `color{Violet}"failed to keep pace"` with demand and to provide sufficiently `color{Violet}"fast and efficient systems"` for crop improvement, another technology called tissue culture got developed.
● It was learnt by scientists, during `color{Violet}"1950s"`, that whole plants could be `color{Violet}"regenerated from explants"`, i.e., any part of a plant taken out and grown in a test tube, under `color{Violet}"sterile conditions"` in special nutrient media.
● This capacity to generate a `color{Violet}"whole plant"` from any cell/explant is called `color{Brown}"totipotency"`.
● It is important to stress here that the `color{Violet}"nutrient medium"` must provide a `color{Violet}"carbon source"` such as sucrose and also `color{Violet}"inorganic salts"`, vitamins, amino acids and `color{Violet}"growth regulators"` like auxins, cytokinins etc.
● By application of these methods it is possible to `color{Violet}"achieve propagation"` of a large number of plants in very `color{Violet}"short durations"`.
● This method of producing `color{Violet}"thousands of plants"` through tissue culture is called `color{Brown}"micropropagation"`.
● Each of these plants will be `color{Violet}"genetically identical"` to the original plant from which they were grown, i.e., they are `color{Brown}"somaclones"`.
● Many important food plants like `color{Violet}"tomato, banana, apple"`, etc., have been produced on commercial scale using this method.
`color{Brown}"Recovery of"` `color{Brown}"healthy plants"` `color{Brown}"from diseased plants:"`
● Another important application of the method is the `color{Violet}"recovery of healthy plants"` from diseased plants.
● Although the plant is `color{Violet}"infected with a virus"`, the `color{Brown}"meristem"` (apical and axillary) is `color{Violet}"free"` of virus.
● Hence, one can remove the meristem and `color{Violet}"grow it in vitro"` to obtain `color{Violet}"virus-free plants"`.
● Scientists have succeeded in `color{Violet}"culturing meristems"` of banana, sugarcane, potato, etc.
`color{Brown}"Somatic Hybridisation:"`
● Scientists have even `color{Violet}"isolated single cells"` from plants and after digesting their cell walls have been able to isolate `color{Violet}"naked protoplasts"` (surrounded by plasma membranes).
● `color{Violet}"Isolated protoplasts"` from two different varieties of plants – each having a `color{Violet}"desirable character"` – can be `color{Violet}"fused"` to get `color{Violet}"hybrid protoplasts"`, which can be further grown to form a new plant.
● These hybrids are called `color{brown}"somatic hybrids"` while the process is called `color{Brown}"somatic hybridisation"`.
● A `color{Violet}"protoplast of tomato"` has been fused with that of `color{Violet}"potato"`, and then they are grown – to form new `color{Violet}"hybrid plants"` combining tomato and potato characteristics- resulting in formation of tomato
● Unfortunately this plant `color{Violet}"did not have"` all the `color{Violet}"desired combination"` of characteristics for its commercial utilisation.