Q. Coconut milk factor is
Solution:
Cytokinins (Cytos = Cell; Kinesis = To divide) are a class of Plant Growth Regulators (PGRs) which primarily promotes cell division in plants. G. Haberlandt, in 1913, first detected the presence of cell-dividing substances in cells of plants.
Coconut milk, which is the liquid endosperm of the plant, is one of the richest sources of cytokinins.
Skoog and Miller in 1954, reported that autoclaved DNA from the herring sperm stimulated the division of cells in tobacco pith cells.
Following characteristic properties are associated with this class of PGR:
1. They are basic, purine-derivative hormones.
2. They are synthesized more in the root apices and are transported to all other parts.
3. For many occasions, they antagonise auxins, another plant hormone class.
4. The main bioassay for this class of hormone is 'Tobacco Pith Culture' and 'Retardation of Leaf Senescence' tests.
Zeatin (6-Hydroxy-3-methyl-trans-2-butenyl-amino purine), Kinetin (6-Furfuryl amino purine), Isopentenyl Adenine (IP) are common cytokinins in plants.
Several physiological functions are controlled by these hormones, like:
I. They promote cell divisions in plants.
II. They delay senescence or yellowing of leaf.
III. They help in phloem transport or the translocation of food through the phloem.
IV. They are most efficient in breaking seed dormancy.
V. They, by antagonizing auxins, can break apical dominance, even in the presence of apical buds.
VI. They increase the shelf-life of several vegetables when applied externally.
VII. They directly influence the synthesis of DNA and RNA in many cells.
VIII. Like auxins as well as Ethylene, they promote female flower production in many plants.
Coconut milk, which is the liquid endosperm of the plant, is one of the richest sources of cytokinins.
Skoog and Miller in 1954, reported that autoclaved DNA from the herring sperm stimulated the division of cells in tobacco pith cells.
Following characteristic properties are associated with this class of PGR:
1. They are basic, purine-derivative hormones.
2. They are synthesized more in the root apices and are transported to all other parts.
3. For many occasions, they antagonise auxins, another plant hormone class.
4. The main bioassay for this class of hormone is 'Tobacco Pith Culture' and 'Retardation of Leaf Senescence' tests.
Zeatin (6-Hydroxy-3-methyl-trans-2-butenyl-amino purine), Kinetin (6-Furfuryl amino purine), Isopentenyl Adenine (IP) are common cytokinins in plants.
Several physiological functions are controlled by these hormones, like:
I. They promote cell divisions in plants.
II. They delay senescence or yellowing of leaf.
III. They help in phloem transport or the translocation of food through the phloem.
IV. They are most efficient in breaking seed dormancy.
V. They, by antagonizing auxins, can break apical dominance, even in the presence of apical buds.
VI. They increase the shelf-life of several vegetables when applied externally.
VII. They directly influence the synthesis of DNA and RNA in many cells.
VIII. Like auxins as well as Ethylene, they promote female flower production in many plants.