Techniques of raising Flowers and plants in greenhouse

Flower reproduction is a means for flowers to reproduce and maintain germplasm resources. only when germplasm resources are preserved and propagated to a certain number can they be used in gardens and provide conditions for flower seed selection and breeding. There are many species and varieties of flowers, and the methods of reproduction are also different, which can be divided into two methods: sexual reproduction and asexual reproduction.

Sexual reproduction: also known as seed reproduction, refers to the reproduction of seeds, such as sowing.

Asexual reproduction: also known as vegetative reproduction, refers to the use of flower vegetative organs (roots, stems, leaves) for reproduction, and then obtain new plants. It usually includes meristem, cuttage, grafting, crimping and tissue culture.

One. Sowing method: the sowing of greenhouse flowers is usually carried out in the greenhouse, which is less affected by the season, and the sowing time is determined according to the required flowering time.

Before sowing, the seeds can be properly treated according to the specific conditions of the seeds, such as those with thicker seed coats can be soaked in warm water or sulfuric acid, and some seeds can be stored in sand.

The sowing soil can be mixed with rotten leaf soil, sandy soil and garden soil, and the proportion depends on the size of the seeds: fine seeds are mixed at 5:3:2, medium seeds at 4:2:4 and large seeds at 5:1:4.

Sowing can be on the hotbed, or utensils such as pot cuttings, sowing drawers and burrowing trays can be used. In addition to the burrowing trays that can directly use sowing soil, hotbeds, potted cuttings and sowing drawers should be small stones or other coarse granular materials-coarse culture soil-sowing soil from bottom to top, accounting for 1 / 3 each.

Small seeds should be sown by sowing, which can be mixed with fine sand or sowed alone. Sowing should not be too dense, while medium and large seeds should be sowed on demand or by strip sowing. Greenhouse flowers suitable for sowing are Begonia, such as Begonia, Begonia, Rieger Begonia, Petunia, Carnation, Green Butterfly, and bluebells.

For small seeds sown, they can be covered with a very thin layer of fine sand or not, but after watering or soaking, a film or glass must be covered above the hotbed and utensils to increase humidity and prevent the seeds from drying. The depth of soil cover after sowing of large and medium seeds depends on the size of seeds. The depth of soil cover of large seeds is 2-3 times of the thickness of seeds, and the degree of small and medium seeds is generally not seen. After sowing, you should pay attention to the humidity of hotbeds and utensils and spray water regularly. Film and other covers should be opened after emergence. For sown seeds, time should be given when the seedlings grow to about 2CM high.

Two. cutting method

The propagation method of using plant vegetative organs (roots, stems and leaves) to form independent plants is called cutting. The plants cultivated by this method grow faster than sowing seedlings, and can be cultivated into large seedlings in a short time, especially some plants which are not easy to blossom, which can blossom earlier for flowering plants, but cuttings have no main root and the root system is weaker than sowing seedlings.

(1) cutting substrate: there are many substrates used for cutting, including soil, sand, perlite, vermiculite and water. Water insertion is a relatively sanitary and simple method, but attention should be paid to changing water frequently, keeping the water clean, cold and boiled, and if it is tap water, it should be hung for 2-3 days. In order to prevent the breeding of bacteria, steel jump and charcoal can be added to the water. Suitable for water planting flowers are variable leaf wood, Araceae (evergreen, tortoise back bamboo, green pineapple, etc.), greenhouse impatiens, begonia (four seasons begonia, silver star crabapple, etc.), banyan (rubber tree, banyan tree, etc.), bean green, rich bamboo, cold water, umbrella grass, duck toe grass, clematis and so on.

(2) types and methods of cutting

According to the different vegetative organs selected, they can be divided into three types: leaf cutting, stem cutting and root cutting.

1. Leaf cutting

It mainly refers to taking the leaves of a plant as cuttings to make it take root and grow leaves, so as to become a complete plant. Generally, these leaves have stout petioles, veins or thick leaves. The choice must be full-grown leaves.

(1) whole leaf cuttings: take intact leaves as cuttings. The leaves can be placed flat on the substrate, but make sure that the leaves are close to the substrate, so the leaves can be fixed with nails, bamboo sticks or substrates, such as crassulaceae (rooting, etc.), begonia (begonia, Oviductus, etc.) The petiole can also be inserted into the matrix, and the leaves are flat or upright on the substrate. This method is suitable for plants that can produce adventitious buds from the base of the petiole, such as paulownia, African violets, Douban green, etc.

(2) Leaf cutting: a complete leaf is cut into several pieces and cut separately, and adventitious buds can be formed on each leaf. Such as tiger tail orchid, paulownia, pepper grass and begonia plants and so on.

2. Stem cutting: cuttings with stem segments as cuttings. According to the different cutting seasons, it can be divided into softwood cuttage and hardwood cuttage. Softwood cuttings are carried out during the growing season, and cuttings are those branches that are not fully lignified. On the other hand, hardwood cuttings are carried out in the dormant period or at the beginning and end of growth, with those completely Lignified branches as cuttings.

3. Root cutting: some flowers can produce adventitious buds from their roots, thus forming new plants, so such roots can be used as cuttings for cutting propagation. The roots used for cutting are generally stout, and some are even slightly fleshy, such as Sugen Flukao, Paeonia lactiflora and so on.

(3) methods to promote rooting of cuttings: in order to make cuttings rooting as soon as possible, some methods can be taken, such as chemical treatment and hormone treatment are very common means. the commonly used hormones are indole butyric acid, indole acetic acid and naphthylacetic acid and rooting powder, and some chemicals such as potassium permanganate and sucrose can be used. Potassium permanganate has a good effect on most woody plants, the general concentration is 0.1-1.0%, and the soaking time is 24 hours. Sucrose is effective for both woody and herbaceous plants, and the treatment concentration is 2-10%. The general soaking time is 24 hours. There are also many physical treatment methods, including annular peeling, spray treatment, hot water treatment, increasing bottom temperature and bottom temperature treatment and so on.

Third, the method of division

This method is one of the methods of plant vegetative reproduction, which refers to the separation of young plants growing on plants, or the separation of part of plant vegetative organs from mother plants and planting to form independent plants. It mainly includes the method of dividing plants and the use of vegetative organs of sucking buds, plant buds and abnormal stems (including walking stem, stolon, climbing stem, rhizome, corm, bulb, tuber).

1. Ramet: the sprouting tillers of the rhizome or underground stem are cut off and planted to form a new plant. Such as Cymbidium, Hosta and so on.

2. Sucking buds: short, thick rosette-shaped short branches naturally occurring in the rhizosphere or aboveground stems and leaves of some plants. Such as aloe and pineapple.

3. Bulbs and surplus seeds: these are special forms of buds of some plants, born in leaf axils or inflorescences, and some flowers of Liliaceae, such as lilies, curls, ornamental onions, and so on. After leaving the mother plant, the bulb and the remaining seeds can take root naturally.

4. State stem: refers to some heritable changes of plant stem in the process of evolution, including morphology, structure and physiological function, in which the main abnormal stems that can be used for reproduction are walking stem, rhizome, bulb, corm, tuber and so on.

The walking stem is the metamorphosis of the aboveground stem, the longer stem is drawn from the leaves, and there are leaves, flowers and adventitious roots on the nodes, and young plants can be produced at the same time. These small plants can be planted separately to form new plants, such stems are called walking stems. The flowers propagated by walking stems include Saxifraga, Chlorophyllum and so on.

The underground stem of some flowers is enlarged, thick and long in shape, similar to the root, which is called rhizome, which stores rich nutrients, which is similar to the aboveground stem, with nodes, internodes, degenerated scale leaves, terminal buds and axillary buds. Adventitious roots are often produced on the nodes, from which lateral buds can be branched to form clusters, which can be separated into independent plants, such as canna, iris, Aster and so on.

The bulb means that the underground stems of some flowers are short and thick and almost spherical, with a flat disk-shaped bulb disk at the bottom, and the scale leaves grow on the scale leaf disc. The bulb is rich in organic matter and water, the terminal bud often produces true leaves and inflorescences, axillary buds can occur between the scales, and one to several bulbs can be formed from the axillary buds and separated from the old bulb every year, so the coefficient can be expanded by dividing the bulbs. Such as lilies, tulips, hyacinths, daffodils and so on.

Bulbs: the underground stems of some flowers are short and hypertrophic and nearly spherical, storing nutrients, upper nodes of the corm, degraded leaves and lateral buds. New balls are formed at the base of the bulbs after germination, and new bulbs are often born next to the new bulbs, which can be divided into new balls and heads in production. Such as Gladiolus, freesia, Cigu and so on.

Tuber: an underground abnormal stem of perennial flowers, which has different shapes and is close to lumps, storing certain nutrients. The root system occurs from the bottom of the tuber, the tip of the tuber usually has several germination points, and some buds can be produced on the surface of the tuber. can be divided into tubers for reproduction. Such as grafting and striping.

(1) grafting: refers to the reproductive method in which a part of one plant is grafted onto another, and its tissues heal each other and are cultivated into independent individuals. This method is mostly used for cutting flowers and trees that are difficult to take root or difficult to get seeds. Compared with the seedlings, the flowers and trees grafted can blossom earlier and maintain the good quality of the scion. There are many flowers and trees that can be propagated by grafting, such as osmanthus, chrysanthemum, cactus and so on.

(2) striping method: a method in which the branches that are about to approach the ground are piled up at the base or buried in the lower part of the soil, while the higher branches are cut with moist soil or moss, waiting for the branches to take root and replant them to become independent plants. This method is used for those species that are not easy to reproduce by other methods, and can maintain the characteristics of the original varieties. This method is used in greenhouse flowers, such as white orchid, camellia, leaf flower, Zhu banana and so on.

IV. Tissue culture method

Through aseptic operation, a part of the explant is inoculated on the culture medium and cultured under the condition of artificial control, so that it can produce complete new plants, which is called tissue culture. The theoretical basis of plant tissue culture is the totipotency of cells, that is, each cell of a plant has all the genetic information of the plant and can develop into a complete plant.

Plant tissue culture is a new technology developed in the 20th century. It not only has important value in the research of basic theory, but also shows its great value in practical application. According to the culture techniques mastered, almost all the isolated parts of plants can be cultured uniformly and uniformly, and the culture conditions can be strictly controlled artificially, that is, the effects of many unfavorable factors, such as seasons, can be ruled out. therefore, in many countries and regions, as an important means of industrial production, it has been widely used in agronomy, horticulture, medicine, forestry and other applied science. It is especially applied to some plants that are not fruiting or the seed setting rate is low. Tissue culture can greatly improve the coefficient of reproduction and save labor at the same time.

Plant tissue culture can be divided into four stages:

The first stage is to establish an aseptic system, that is, disinfection and inoculation of explants and culture media to obtain calli or organs.

The second stage is mainly for proliferation, continuous differentiation to produce new plants, or direct production of adventitious buds and embryoids, and can also be subcultured repeatedly as needed to achieve the purpose of mass propagation.

The third stage is to transfer the plant for rooting culture, which can be transferred to the rooting medium or cut directly for cutting rooting.

The fourth stage is the excess of test-tube plantlets, that is, the adaptation process of test-tube plantlets to the external environment for a certain period of time after coming out of the bottle.

Plant tissue culture needs a certain site, instruments and equipment, including a series of laboratories (aseptic room: an important place for inoculation, the area does not have to be very large, but it must be sealed and clean, chemical laboratory: it is a place for preparing reagents and culture media, and culture rooms: places for test-tube plantlets. Equipped with culture rack air conditioner, washing room: special place for washing all kinds of glassware, sterilization room: mainly for culture medium, glassware and tools for disinfection and sterilization, and cytology laboratory can carry out a series of observation and analysis, etc.), thermostat, oven, refrigerator, balance, acidity meter, high pressure sterilizer, distilled water generator, microscope, etc., and some glassware (triangle flask, capacity bottle, petri dish, etc.) Beaker, measuring cylinder, etc.

The culture conditions vary with different plant materials, but the temperature is 25 ℃, the light intensity is 22000lux, the irradiation time is 8-10 hours per day, and the PH value of the medium is between 5.0 and 6.5. Of course, it can be adjusted according to the actual situation.