Tissue Culture Importance
Plant tissue culture is one of the most rapidly growing areas of biotechnology because of its high potential to develop improved crops and ornamental plants. With the advances made in the tissue culture technology, it is now possible to regenerate species of any plant in the laboratory. Application in Research Work: Tissue culture techniques […]
Plant Tissue Culture Techniques
CALLUS CULTURE Callus is amorphous mass of loosely arranged thin walled parenchyma cells developing from proliferating cells the parent tissue. Plants are regenerated by forming a normal shoot, root and embryoids ultimately forming a plant. Importance: Plant breeding: Callus culture provides genetic variability which is important for successful plant breeding. Somaclonal variations: Many agriculturally useful […]
Plant Tissue Culture
Plant tissue culture broadly refers to the in vitro cultivation of plants, seeds and various parts of the plants (organs, embryos, tissues, single cells, protoplasts). The cultivation process is invariably carried out in a nutrient culture medium under aseptic conditions. History of Plant Tissue Culture Callus Culture Method German botanist Gottlieb Haberlandt (1902), regarded as […]
Mineral Nutrients Required by Plants
Element Physiological Roles Deficiency symptoms NITROGEN Proteins, chlorophyll, nucleic acids. Cell membranes Enzymes, coenzymes etc. Chlorosis, Leaf fall Stunted growth Poor flowering SULPHUR Amino acids; Methionine, cysteine, Vitamins, biotin, thiamine, Coenzymes etc. Leaf fall, Leaf rolling Chlorosis Inhibition of apical bud Young leaves affects first PHOSPHORUS Proteins, nucleic acids. Cell membranes ATP, ADP, NADP Oxidation […]
Dormancy
During seed maturation , the embryo enters a quiescent phase in response to desiccation. Seed germination can be defined as the resumption of growth of the embryo of the mature seed; it depends on the same environmental conditions as vegetative growth does. Water and oxygen must be available, the temperature must be suitable, and there […]
Abscisic Acid
Unlike auxins, gibberellins, and cytokinins, the hormone abscisic acid(ABA) is represented by a single 15-carbon sesquiterpene. ABA also appears to have a more limited range of speciļ¬c effects than auxins, gibberellins, and cytokinins. THE DISCOVERY OF ABSCISIC ACID As more investigators became interested in plant hormone research, it soon became evident that ether extracts of […]
Ethylene
During the 19th century, when coal gas was used for street illumination, it was observed that trees in the vicinity of streetlamps defoliated more extensively than other trees. Eventually it became apparent that coal gas and air pollutants affect plant growth and development, and ethylene was identified as the active component of coal gas. Dimitry […]
Cytokinins
The cytokinins were discovered in the search for factors that stimulate plant cells to divide (i.e., undergo cytokinesis). Since their discovery, cytokinins have been shown to have effects on many other physiological and developmental processes, including leaf senescence, nutrient mobilization, apical dominance, the formation and activity of shoot apical meristems, floral development, the breaking of […]
Gibberellins
Gibberellins are members of a large and varied family of plant constituents known as the terpenoids. Terpenes are normally recognized on the basis of their chemical structure, which may be dissected into one or more 5-carbon isoprene units. Gibberellins are thus biosynthetically related to the carotenoid pigments, sterols, latex, and other isoprene. Gibberellins are noted […]
Auxins
The first plant hormone we will consider is auxin. Auxin deserves pride of place in any discussion of plant hormones because it was the first growth hormone to be discovered in plants, and much of the early physiological work on the mechanism of plant cell expansion was carried out in relation to auxin action. Darwin’s […]