What are wholesale tissue culture plants?
Tissue culture plants are plantlets grown from explants on a medium containing specific nutrients for the development of the cells. These explants may be from any part of the plant.
Tissue culture has proven beneficial for the production of disease-free and high quality planting material. This technique is a traditional method used in many developing countries.
Micropropagation
Micropropagation is the technique of generating large numbers of genetically identical plants from a small part. It is often used to multiply plant stock materials such as seeds, roots or grafts and then transplant the progeny plants into the field for growth.
MicroPropagation can be performed using wholesale tissue culture plants or cell culture techniques. The primary objective is to improve crops by introducing asexual selection and genetic manipulation techniques.
This is done by culturing apical meristems (clones) of the same plant and growing them under a controlled environment to produce more plants than would be possible if propagated by normal means. This method is also known as meristem culture, clonal propagation or mericlones.
The meristems are then grown under controlled conditions in vitro to grow into plants that are genetically identical to the original plant from which they were produced. After these plants are grown and rooted, they are transferred into a growth medium to develop further until they are ready to be transplanted in the field.
Plantlets and shoots are often grown in a medium containing auxins to stimulate root formation. A pretransplant treatment is also often performed to encourage root growth and “hardening” of the plantlets prior to planting. This is often a very difficult process but requires careful execution.
A key disadvantage of the process is that it is expensive, especially for plants that have not been cultivated for many years. In addition, it can be a slow process to produce enough new plants for market.
Consequently, micropropagation is often outsourced to contractors in developing countries, where the cost of labour is less. The plants are then marketed and sold at wholesale prices to consumers.
Another important benefit of the process is that it can be carried out year round. This means that a nursery can produce fruit, ornamental and tree species throughout the year. It can also be used to produce disease free varieties.
In some cases, this can be more effective than other forms of propagation such as grafting and layering cuttings. For example, some orchids are unable to be propagated by other methods and can only be grown in this way.
Organ Culture
Organ culture is a technique that stems from tissue culture methods, but instead of removing tissue fragments, it involves culturing whole organs or parts of an organ in vitro. The main aim of the process is to preserve the organs normal architecture and direct them towards normal development.
During the last several decades, organ cultures have played a critical role in the study of organogenesis. They allow us to obtain a detailed analysis of the processes and mechanisms involved in the growth and development of organs such as kidneys, livers, heart, and lungs.
Many organs are also cultivated to determine their response to various biotic or abiotic conditions, including radiation. This can be helpful in understanding how a specific disease may arise, as well as to identify the mechanisms of action of an agent.
In addition, organ culture can be used to study the effects of toxins and toxic compounds on cells in an organism. This can help us to better understand the pathogenesis of certain diseases or the interaction of drugs and toxins in the body.
For example, lenticular opacities of the cornea are a result of a variety of toxic insults. Therefore, it is useful to culture bovine or mammalian lenticular epithelial cells to evaluate the potential cataractogenicity of a given compound.
Organ culture is also an important tool in studying the effects of cancer chemotherapy on the endocrine glands and other tissues. This can be done by culturing cells from the human, mouse, or bovine adrenal cortex to evaluate the effects of cytotoxic chemotherapy on these tissues.
The use of organ culture to study the effects of chemotherapeutics has become increasingly common, particularly in the treatment of diseases such as hepatocellular carcinoma and leukemia. These studies have revealed a wide range of reactions from the immune system to the inflammatory response and the effects of cancer therapy on different tissue types.
The organ cultures are maintained alive through partial immersion in a nutrient medium, which must be kept at a constant pH. These conditions can be altered by adding or removing nutrients. The cells in the culture can be observed using a microscope or by spectroscopy.
Callus Culture
Callus culture is a form of plant tissue culture in which explants are grown in vitro on a medium supplemented with growth hormones. This method is a very effective way to recover tissues from wounded plants, and it can be used to study plant development, or to generate transgenic plants with improved features such as salt or drought tolerance.
Calli (plural calluses or calli) are a type of non-differentiated, heterogeneous, unorganized parenchyma cells that grow in response to cytokinin and other plant growth regulators. They can be generated from almost any part of a plant. These cells are also called ‘wounded tissue’ or ‘wounded parenchyma’ and represent a unique form of plant tissue.
The term ‘callus’ was coined by American pathologist Montrose Thomas Burrows, who observed calli growing over the wound of an elm tree. Although these calli were initially considered to be dead cells, they have since been found to be alive and actively growing in vitro.
In order to stimulate the initiation of callus, explants were first surface sterilized and plated onto tissue culture medium in vitro. The tissue culture medium was then supplemented with plant growth regulators, such as cytokinin and auxin, to trigger the cell proliferation process. Once induced, leaf and fruit calli were isolated from the explants and cultured in N30K medium supplemented with 11.3 uM 2,4-D. The callus was then subcultured to fresh medium at 4 week intervals until a single cell line was obtained.
When calledus is cultivated under controlled conditions, it has the potential to yield a wide range of bioactive secondary metabolites, and extracts prepared from calli are able to act as anticancer agents against four different cancer cell lines. In addition, callus culture extracts have been shown to inhibit apoptotic processes in several human tumor cell lines.
Another important use of callus cultures is to insert genes into the calli. These genes are then injected into the callus using a gene gun, Agrobacterium tumefaciens.
This technique can be used to produce genetically modified plants with enhanced agronomic traits, such as resistance against heat, water stress, salt stress, and microbial attack. The resulting plants can be used to produce food, feed, or other products for humans and animals.
Orchid Culture
Orchids are one of the largest flowering plant families, with more than 25,000 varieties to choose from. They have been cultivated for thousands of years and are prized for their variety in appearance, color, size, and fragrance.
Orchid culture involves a number of processes, including vegetative propagation (using bulbs or offshoots), spore production, and sexual reproduction using seed capsules. The process of establishing orchid tissue cultures can be difficult and time-consuming, but it can also yield exciting results.
Propagating an orchid from seed requires a high level of skill and expertise. In nature, orchid seeds are non-endospermic, meaning they lack the nutritional storage tissues that help other seedlings establish roots. Instead, seeds must land where fungi are present to convert nutrients into the plant’s useable form.
Unlike other seeds, orchids can produce hybrids between species and between related genera. This ability to create a mind-boggling array of genetically distinct plants has helped to make orchids one of the most diverse and fascinating groups of flowering plants.
Hybrids are produced by combining the pollen of different types of flowers or by crossing different orchid species. This enables breeders to create new cultivars of orchids and add even more colors and shapes to the palette of these plants.
To propagate an orchid from a bulb or offshoot, you need to remove the plant’s outer leaves and replant it in a larger container with new potting media. You can use a mix of fine gravel, pebbles, and coarse sand or sphagnum moss.
Potting is a critical step in the process of growing an orchid, as it allows water to flow around its roots and prevents them from drying out. The potting media should be loose enough to allow air circulation.
Before repotting, inspect the roots to identify any that are blackened or spongy and cut them off. If the roots are healthy, they will be white or green and appear to be free of cracks.
Next, fill the pot with new potting media and tamp down gently to about an inch from the top of the pot. Water well to settle the media around the roots and then place the plant in the new container, staking it as necessary until it takes hold of the new media.