ABSTRACT
The Science of Plant Tissue Culture (PTC) means aseptic cultivation of plant protoplasts, cells, tissues, organs or complete plantlets in vitro, i.e. “in glass” in certain culture media and their incubation under controlled physical conditions like light, temperature and humidity. It provides the best system for experimental research where all the factors acting upon the explants are within control and can be varied selectively to pinpoint the causal factor/s for a particular response. To be precise, in PTC, one studies in vitro morphogenesis to understand the process of chemical regulation of growth and differentiation – both morphological and biochemical – with the aim of unravelling the underlying causal processes and mechanisms, the least understood aspects of development. Morphogenesis reveals in succession the genetic information in a most orderly sequence as reflected in differentiation and developmental events to give a format, which is species specific. When the cells and tissues are freed from the restrictions imposed by the organisation of a whole individual, these can be induced to forget their commitments as a part of the organisation, and differentiate and develop as an individual entity, since these possess the complete genetic information for programming the development of a whole individual as well as different chemical pathways for synthesising a whole array of metabolites. As such, for understanding the discipline of morphogenesis, knowledge of such other branches of science as Morphology, Anatomy, Embryology, Cytology, Genetics, Pathology, Physiology, Biochemistry, and Molecular Biology is required. In the Polar Regions, the biotechnological processes have variant characteristics due to varied geo-physical conditions.
