Although plants have no nerves, their cells are also conductive, which makes plants feel. For example: maple 1 is bitten by a bug, it will immediately release pheromone to inform maple 234: I am attacked, be careful! Therefore, the maple tree 234 immediately releases pheromones, which annoys the bugs and makes them leave. This is why the biology book tells us that crops with insect-resistant characteristics should be mixed with "insect-trapping" crops such as vegetables.
Compared with direct planting crops, tissue culture has the following advantages:
1, which occupies a small space and is not limited by regions and seasons.
2. Cultivate virus-free crops
3, the culture period is short
4. Callus in tissue culture can make special biochemical products.
It can reproduce in a short time and be used to save endangered plants.
6. Induce differentiation into required organs, such as roots and buds.
7. Solve the problem that some plants have few or no seeds.
8, no variation, can maintain all the genetic characteristics of the original female parent.
9. Less investment and high economic benefits.
10, there are many breeding methods and many trials.
About plant tissue culture:
Cultivation method:
1, rapid propagation of non-test-tube tissues
Non-test-tube micro-tissue rapid propagation technology is to culture explants (usually one leaf and one bud) on indoor and outdoor common sandy medium, and to achieve the purpose of rapid propagation by using the natural proliferation of plant axillary buds. General plants can take root in 7 ~ 15 days. This technology has less investment and fewer operation links.
2. Tissue culture in vitro
In vitro tissue culture is to put explants (that is, in vitro tissues, organs or cells) in tissue culture bottles and other containers for tissue culture under aseptic conditions to obtain tissue culture bottle seedlings.
Specific steps:
The first step is to remove the unused parts of the collected plant materials and wash the needed parts carefully, such as with a suitable brush. Cut the material into appropriate sizes, that is, it is appropriate to put the sterilization container in. Put a faucet and let the water flow for several minutes to several hours. The washing time depends on the cleanliness of the material. Float-prone or fine materials can be washed in gauze bags. When the pollution is serious, running water washing is particularly useful. When washing, you can add washing powder to clean it, and then rinse the washing powder with tap water. Washing powder can remove dirt slightly attached to the surface of plants, remove lipid substances and facilitate direct contact with disinfectant. Of course, the most ideal cleaning substance is the surface active substance-Tween.
The second step is to soak and disinfect the surface of the material. To finish it in a clean workbench or inoculation box, prepare a sterilized beaker, glass rod, 70% alcohol, disinfectant, sterile water, watches, etc. Soak in 70% alcohol 10 ~ 30 seconds. Because alcohol can make the surface of plant materials wet, 70% alcohol has strong penetration and is easy to kill plant cells, so the infiltration time should not be too long. There are also some special materials, such as if, bud, booting stage with bud and bud, dormant bud with multi-layer scales and so on. And it is mainly made of internal materials, which can be treated with 70% alcohol for a little longer. Under aseptic conditions, the treated materials will be peeled off after the alcohol volatilizes, and the internal materials will be used.
The third step is to treat with disinfectant. There are many kinds of surface disinfectants, and 1-2 can be selected according to the situation. See table. Step 4, rinse with sterile water for about 3 minutes each time, and rinse for about 3- 10 times according to the type of disinfectant used. The washing function of sterile water is to avoid the side effects of disinfectant killing plant cells. note:
① Alcohol has strong permeability, and young wood is easy to lose green in alcohol, and the soaking time should be short to prevent alcohol from killing plant cells.
2 Mature materials, especially seeds, can be soaked in alcohol for a long time, for example, seeds can be soaked for 5 minutes.
(3) The penetration of mercuric chloride is weak, and it is generally soaked for about 10 minute, which does little harm to plant materials.
(4) Bleaching powder is easy to cause plant materials to lose green, so young materials should be used with caution.
⑤ Adding Tween 20 or 80 (a wetting agent) with the concentration of 0.08-0. 12% to the disinfectant can reduce the surface tension of plant materials and achieve better disinfection effect.