How to propagate the tulip tree? Key points of seed sowing and cutting techniques

The tulip tree, also known as the Chinese tulip tree, has a very distinctive appearance and the beautiful name "tulip tree of China." It is a very precious street tree and courtyard ornamental tree species in our country. However, the tulip tree is relatively difficult to propagate, and its survival rate is also relatively low, so its popularity in our country has been declining.

Tulip tree

I. Seed propagation

Propagate by seed. Artificial supplementary pollination must be used. In autumn, after the seeds are collected and selected, they are stratified in moist sand to overwinter, and sown and raised as seedlings in the following spring. In the third year, when the seedlings are more than 1 m tall, they can be lifted from the nursery and planted out. The afforestation site and landscaping site must be chosen in deep, fertile, well-drained places. When transplanting, the roots should be protected.

1. Seed collection

The mother tree should preferably be a robustly growing tree 15-30 years old. Tulip tree seeds mature in October, and when the fruit turns brown it should be harvested. After the fruiting branches are cut off, place them indoors in the shade to dry for about 7-10 days, then spread them in sunlight to dry for 2-3 days, wait for the winged nutlets to separate on their own, remove impurities, and store them dry in cloth bags.

2. Raising seedlings

The seedling-raising site should be chosen as a wind-sheltered, sunny place with deep soil, fertile and moist, and well-drained sandy loam. Deep plow in late autumn and early winter, apply basal fertilizer and level the ground in the following spring, dig drainage ditches well, build raised beds, with the seedbed oriented east-west. There are two methods of raising seedlings: sowing and cutting.

Sowing for seedling raising uses drill sowing, with row spacing of 20-25 cm. The sowing rate per mu is 10-15 kg. Sow in early March, and after sowing cover with fine soil and then rice straw. Generally, seedlings emerge after 20-30 days, after which the straw is removed, and attention should be paid to timely cultivating and weeding, moderate shading, and timely irrigation and fertilization. One-year-old seedlings can reach 40 cm in height.

3. Planting

Generally, planting is carried out in early to mid-March. It should be chosen in relatively shady valleys and the middle and lower parts of slopes. For courtyard landscaping and street tree cultivation, sections with deep, fertile, and moist soil should be selected. The planting site should be thoroughly cleared in late autumn and early winter, with holes dug at fixed points, hole diameter 60-80 cm, depth 50-60 cm, and planting carried out in early to mid-March of the following year after fertilizing and backfilling soil. The seedlings used are generally 2-year-old; after lifting the seedlings, take care to prevent moisture loss from the seedlings and protect the root system, and plant as soon as possible after lifting, with a spacing of 2 x 2 m to 2 x 3 m being suitable.

4. Management

After planting out, timely carry out cultivating and weeding, fertilization, and earthing up, and prune branches every year in late autumn and early winter. Also pay attention to the prevention and control of pests and diseases. The main disease of the tulip tree is sunscald. The main pests include leaf roller moths and bagworms. Leaf roller moths can be controlled by manually cutting off dead tips to destroy larvae and pupae, or by spraying 50% dichlorvos emulsion at 1000 times dilution during the adult stage. Bagworms can be controlled by manually removing the worm bags, or by spraying 90% trichlorfon at 800-1000 times dilution to kill the larvae.

II. Cutting propagation

Besides sowing for seedling raising, the tulip tree can also be propagated by cuttings. In the southern Henan region, hardwood cuttings are mostly used; this seedling-raising method is simple and easy to learn and master. After leaf fall, in late February of the following year, select robust mother trees and cut one-year-old branches more than 5 mm thick as cuttings, with a cutting length of about 15 cm, each cutting should have 2 to 3 plump buds, the lower end cut flat, and inserted into the soil at a spacing of 20 cm x 30 cm to 3/4 of their length; before cutting, they can be soaked in rooting powder for about 30 minutes. The cuttings should be inserted as soon as they are collected; after insertion, shading facilities should be provided and water sprayed frequently. This method can achieve a seedling formation rate of 80%, and one-year-old seedlings grow to more than 80 cm and can likewise be lifted from the nursery for afforestation.

Examples of rapid propagation techniques for fruit tree plants

Examples of rapid propagation techniques for fruit tree plants

I. Rapid propagation of fruit tree plants;

1. Significance of rapid propagation of peach
At present, peaches are basically propagated by grafting, and the cultivation time is generally 1-2 years, so the propagation efficiency is not high, the spread of superior varieties is slow, and it is difficult to meet the urgent demand of the industry for new varieties. In addition, some peach varieties that require special rootstocks for trait improvement or increased site adaptability, such as the replant-resistant rootstock GF677, need vegetative propagation, usually by tissue culture, which is costly and difficult to popularize. There are also cases required by cultivation models, such as the stumping system of meadow orchards, which requires rapid propagation of own-rooted seedlings for cultivation. In addition, the production of peaches using rapidly propagated own-rooted seedlings has the excellent characteristics of earlier fruiting and earlier high yield. The implementation of these techniques all requires the use of a simple and practical rapid propagation technique to solve the special demand for planting stock in production. Here, a brief introduction is given to the application of plant non-test-tube cloning technology in peach trees and the rapid propagation operating procedure.
2. Mother stock cultivation and material pretreatment
Under conventional conditions, peach belongs to the varieties that are relatively difficult to root, which is related to the plant's species characteristics and periodic physiological status. Although there are many peach varieties, and the rooting difficulty and characteristics of each variety differ somewhat, the use of non-test-tube rapid propagation technology can minimize such differences and standardize the operating criteria. Only by understanding the obstacle factors to peach rooting can a rapid propagation plan be formulated. The factors affecting peach rooting differ among varieties, and variety differences ultimately manifest as differences in growth characteristics, causing differences in the physiological state of detached materials. Therefore, regardless of the variety, the mother stock orchard should first be managed under a unified standard model to narrow variety differences,

and obtain relatively consistent rooting results. In addition, differences in different growth stages of the mother plant, differences between the dormant period and the growing period, as well as differences in branch age and leaf age, lead to physiological differences in detached materials; these can also be resolved through mother stock management and pretreatment. Here, corresponding countermeasures are formulated based on the analysis of peach varieties and strains. Peach of northern strains often has a high chilling requirement and a deeper degree of winter dormancy, while southern varieties have shallow dormancy and a low chilling requirement. The reason for the depth of dormancy is the ecological adaptability formed in the process of evolution in different regions; it achieves the depth of dormancy through the level of endogenous abscisic acid content. Endogenous abscisic acid can be artificially regulated through management and technical measures. For example, when rapid propagation is carried out during the dormant period after leaf fall, before rapid propagation it is best to subject the branches to artificial chilling to break dormancy before rapid propagation; otherwise, the survival rate is extremely low. When rapid propagation is carried out during the growing season, the factors affecting rooting are mainly differences caused by endogenous hormones and the level of carbon source accumulation, which manifest as different degrees of tenderness and locations of shoots. These can be achieved by pinching shoots in the mother stock orchard, or by applying pp333 chemical control measures, or by promoting growth with fertilizer and water and heavy pruning to promote sprouting to raise endogenous growth hormones, or by combining exogenous spraying of gibberellin and auxin to regulate plant growth and development. In short, cultivating mother plants with sufficient nutrition, robust shoots, and dark green leaves is the key to achieving efficient rapid propagation of various varieties. In addition, some auxiliary measures can also be combined for detached materials to achieve moderate regulation. For example, treating the cut with magnetized water can increase the survival rate, VB treatment can accelerate the manifestation of the effects of endogenous hormones, and sugar supplementation at the cut can increase the total sugar of young materials and promote the activation of cells at the cut. For deeply dormant northern varieties, winter hardwood detached materials can also be combined with running water treatment to reduce endogenous abscisic acid and other rooting-inhibiting substances. High-concentration exogenous IBA treatment can also be used, such as 1000 ppm treatment for 1-2 hours, which can enable extremely difficult-to-root varieties to root. Usually, for easier-to-root peach varieties, a 10-15 second quick dip is sufficient, while for growing-season rapid propagation of leafy detached materials, only 100-200 ppm indolebutyric acid treatment is needed to achieve the desired effect.

3. Inoculation for rapid propagation and seedbed management
Place the chemically treated detached materials into an intelligent seedbed using perlite as the substrate for rapid propagation. In early spring, the substrate temperature is low, which is the limiting factor affecting rooting. Start the heating wire laid at the bottom of the seedbed for automatic heating, controlled above 15°C. Under such a substrate temperature environment, 5 days after inoculation of the detached materials, initial root primordia differentiate from the parenchyma cells of the secondary phloem outside the cambium; initial roots form in 15-20 days, and after hardening off, transplanting can be carried out on days 25-30. For rapid propagation of green branch detached materials in summer, the limiting high temperature of the air is 35°C. When it exceeds 35°C, automatic micro-sprinkling cooling is carried out. Generally, after rapid propagation of green branch detached materials, root primordium development begins in 7-10 days, some root primordia protrude through the cortex to form root systems in 10-15 days, root systems are basically formed in 15-20 days, and after hardening off, transplanting can be carried out in 20-25 days. During the rooting process, those that root quickly are mostly thick and robust materials with sufficient nutrient accumulation and materials with good leaf photosynthetic function, because during the rooting process a large amount of soluble sugar is needed to participate in metabolism before the root primordium genes can be activated. Therefore, for some peach varieties that are relatively difficult to root, magnetic water treatment can be used to increase α-amylase activity, which has a good catalytic function for rooting. Combined with the comprehensive effects of a magnetized seedbed and magnetized misting, some varieties that are difficult to root under ordinary environments can also be effectively addressed.
In seedbed management, generally it is only necessary to start the expert mode of the intelligent control system. If some overly tender materials are encountered, forced supplementation of carbonated water and oxygen-enriched water can also be combined to promote rooting. In daily management, if some fallen leaves or rotting materials are encountered, they should be promptly cleaned up, and the surroundings should be disinfected with electrolyzed functional water, applied by local watering, to prevent cross-infection.

4. Technical summary
For peaches, regardless of variety or strain, as long as their rooting characteristics are understood, limiting factors are analyzed, and corresponding operating procedures and solutions are formulated, a rooting survival rate of more than 80% can be achieved. For some relatively difficult-to-root varieties, seedlings with strong juvenility are usually used as mother stock to achieve propagation of seedlings from seedlings, which can activate the rooting genes. Moreover, as the number of cycles increases, the rooting time becomes shorter and shorter. This rooting characteristic follows this rule whether in peaches or other fruit trees. Longan conventional seedling raising usually uses grafting, which is slow and can result in poor scion-rootstock compatibility, leading to severe premature aging. Air-layered seedlings, on the other hand, have a low transplanting survival rate, cause too much damage to the mother tree, and have a low propagation coefficient. To address the above problems, non-test-tube cloning technology was successfully developed, which can be lifted from the nursery about 1 year earlier than grafted seedlings. It effectively improves the seedling-raising speed and propagation coefficient, and greatly accelerates the demand for planting stock in the industrialized development of longan.
Longan belongs to the extremely difficult-to-root varieties, mainly because it contains a large amount of rooting-inhibiting substances in its body, and in addition its rooting type is the callus rooting type, so it stays in the seedbed for a longer time, generally requiring about 60-80 days before transplanting. Therefore, in terms of management and production cost, the requirements are stricter than for other planting stock. For difficult-to-root plants, a detached material collection orchard established with seedlings as mother stock can be used, and fine management must be carried out to promote the development of robust and highly vigorous strong branches as detached materials. When summer light is too strong, the mother stock also needs shading treatment, that is, covering with shade netting, which is relatively effective for reducing rooting-inhibiting substances in the body. In addition, gene activation treatment of the mother trees before rapid propagation is also needed, spraying foliar fertilizer or growth hormones on the leaf surface, so that the detached materials can be in a state of superior vigor during rapid propagation.

When preparing detached materials, double-bud materials with 2-3 small leaves are best, especially for varieties containing rooting-inhibiting substances, smaller is more suitable, but they should not be too small, such as taking single buds, because single-bud detached materials are too small and have poor adaptability and stress resistance to external environmental changes, which undoubtedly brings difficulty to long-term seedbed management. Double-bud materials with 2-3 small leaves are optimal. When preparing materials, it is the same as for other plants, but when collecting materials, semi-lignified materials must be selected, that is, materials that are light green, dark green, and light brown; the degree of lignification should not be too high, because the higher the degree of lignification, the more inhibitory substances accumulate in the body.
Treat the prepared detached materials with 200 ppm IBA for 1-2 hours; it is best to prepare the rooting-promoting solution with magnetized water, as the effect will be even better. Immediately after treatment, propagate the materials in an intelligent rapid propagation seedbed using perlite as the substrate, and adjust the system settings. During the management period, in addition to routine management, a certain 1-5 ppm IBA solution can be sprayed on the leaves every 7-10 days, which can be added together with nutrient solution for supplementation, and 1-3 ppm sodium nitrophenolate can also be added and mixed into the nutrients as a cell activator, playing a role in promoting cell activation and rapidly restoring division and differentiation. Under strong light and high temperature in summer, moderate shading with shade netting is also needed, with 60%-70% light transmittance being preferable, and oxygen-enriched water and carbonated water should also be supplemented periodically. After the above comprehensive technical measures, generally the rooting survival rate of longan can also reach more than 80%. Among the current techniques used for the cultivation of vegetative longan seedlings, this is the propagation technique with the highest survival rate and can be promoted and popularized in production.

The seedlings used in papaya cultivation, if produced from seeds through sowing and germination, are all called seedling plants. In papaya cultivation up to now, no matter which variety, seedling plants are used. Because papaya has complex genetic factors, the trait expression of seedling plants within a variety differs greatly depending on the traits of the paternal and maternal plants at the time of sowing. For example, Tainung No. 2 is a first-generation hybrid; when collecting seeds, if a bisexual plant is used as the paternal parent and a female plant as the maternal parent, then among the resulting progeny seeds, 50% of the seedling plants will be bisexual plants and 50% will be female plants. If the traits of the paternal and maternal plants are changed, the sex of the seedling plants after seed collection will vary greatly, with bisexual plants, female plants, or male plants all having a chance of appearing. The identification of the traits of such seedling plants is still impossible to distinguish up to now, and must wait until the plants grow to the flowering stage.

When ordinary farmers cultivate papaya, bisexual plants do not need artificial pollination to set fruit, while female plants, because they themselves lack stamen pollen, must be artificially pollinated. Because the fresh fruit consumer market prefers the bisexual fruit produced by bisexual plants (commonly known as spring fruit) and the price is high, while the female fruit produced by female plants (commonly known as mother fruit), because of its thin flesh and many seeds, is relatively unwelcome to consumers and the price is lower, so when planting the same papaya variety, the planting density is doubled, and when the plants flower, the female plants are cut down, leaving only bisexual plants. This not only saves the labor cost of pollination, but also allows the production of the bisexual fruit required by the consumer market.

The use of non-test-tube cloning allows the traits of the mother plant to be known in advance, and excellent mother plants and bisexual plants can be rapidly propagated in a targeted manner, which can greatly reduce production costs and improve fruit quality. It is currently the most effective papaya propagation technique, and its promotion and application will bring great practical significance to papaya production. The relevant rapid propagation techniques are briefly introduced below:
After selecting excellent papaya plants, cut off the terminal bud between April and September. After an average of 25 days, lateral buds on the trunk immediately below the terminal bud cut will extend into 5-7 lateral branches 30-40 cm long. Cut these lateral branches from the base and keep 3-5 leaves, treat the cut with IBA 2000 ppm, then rapidly propagate them in a substrate mixed with vermiculite + perlite at 1:1. Start the intelligent system, and roots can generally form after an average of 20 days. After another 10 days of rejuvenation, they can be planted out in the field.
After the lateral buds near the terminal bud are harvested, this section of trunk bearing the lateral buds can be cut off, and then the buds below the cut can sprout and grow again into lateral branches. Proceeding in this order, each plant can cultivate lateral branches four times from April to September, with an average total lateral branch production of 24. However, when one leaf and one bud are taken as material, this can be increased several times, but the cultivated seedlings are smaller in specification; when there are few mother plants, one leaf and one bud can be used. When the trunk is cut to about 30 cm above the ground, the trunk can be recultivated to continue producing lateral branches for the coming year. For lateral branches cultivated from the trunk, the rooting rate of rapid propagation can reach 100%, and the rooting time is relatively short. In autumn and winter, due to low temperature, lateral branches are not easy to cultivate, and the average rooting rate is only 85%.
The rapid propagation seedlings from lateral branches cultivated from the same plant, because of vegetative propagation, all have the same characteristics as the mother plant; that is, if the mother plant is a bisexual plant, all the rapid propagation seedlings obtained from it are bisexual plants, and female plants or male plants will no longer appear. In this way, production costs can be greatly reduced and economic benefits improved.
II. Rapid propagation of landscaping plants;
(I) Rapid propagation technique of Chinese tulip tree

The Chinese tulip tree (also known as the tulip tree) grows fast, has good timber, a peculiar leaf shape, and a straight trunk. The hybrid Chinese tulip tree cultivated by artificial crossing has a beautiful tree form, peculiar leaf shape, gorgeous flowers, and golden autumn leaves. It has strong resistance to pests and diseases, its own litter causes no pollution, is fast-growing, has excellent timber, and has strong adaptability. It is a famous excellent timber and landscaping tree species in our country. However, because the seed-setting rate is low, generally only 1%-3%; cutting is difficult, with the rooting rate usually less than 30%; and coupled with improper seedling-raising techniques such as seed treatment, the planting stock production rate is very low, seriously restricting the development of this excellent broadleaf tree species.

To solve this practical production problem, the use of plant non-test-tube cloning technology can achieve a survival rate of more than 93%. The relevant techniques are briefly introduced below: before budding in early spring, take 7-8 cm branch segments as detached materials, soak them in 200 ppm indolebutyric acid solution for 2-4 hours, and propagate them in an intelligent seedbed. Generally, callus tissue begins to form in 15 days, and root systems form in 25-30 days, with a survival rate of more than 95%.
In the growing season, take one leaf and one bud as detached materials, treat with 100 ppm indolebutyric acid for 1-2 hours. Propagate in an intelligent seedbed, with leaves not overlapping as the criterion. Generally, rooting occurs in 20-25 days, and transplanting can be carried out in 30-35 days. The root system is well developed and the survival rate is high, making it the most practical technique for Chinese tulip tree propagation.
(II) Rapid propagation technique of red maple
Usually red maple is propagated by seeds and grafting, with a long seedling-raising cycle, and traditional cuttings are difficult to survive. However, the use of plant non-test-tube cloning technology can achieve a very high rooting survival rate and is the most effective technique for achieving rapid propagation of red maple. Red maple belongs to the difficult-to-propagate varieties.
The rapid propagation substrate is best vermiculite or perlite. Under full-light intelligent seedbed conditions, a better rooting effect can be achieved. This is because under full-light conditions, the photosynthesis of red maple is not affected, and the transpiration of detached materials and water supply are in a balanced state. At the same time, naphthaleneacetic acid can strengthen the cellular tissue activity of detached materials, promote the differentiation of root primordia in detached materials, and advance rooting.
Selection of detached materials and detached materials for rapid propagation of red maple require robustness and thickness, with a diameter of 0.5-1 cm; semi-lignified is superior, tender branches are medium, and old branches are inferior. Each segment is about 5-10 cm long, retaining 1-3 leaves. At the same time, the leaves also need to be trimmed; for one leaf, 1/3 or 1/2 should also be cut off. The lower end of the detached material is cut into a slant, and if necessary the cortex at the base can be wounded, soaked in 500-1000 ppm naphthaleneacetic acid for 5-10 seconds. One leaf and one bud branch segments of red maple can also be taken directly as detached materials, with the cut treated with 100 ppm indolebutyric acid for 2 hours. During the operation, try to cut, treat, and inoculate in sequence; if the detached materials are far from the seedbed, the cut branches should be wrapped well with a wet towel to prevent water loss from the detached materials and avoid affecting rapid propagation survival.

For red maple, people formerly consistently believed that vegetative propagation was difficult and the survival rate was low, so vegetative propagation methods were seldom used to cultivate planting stock, and traditional grafting was mostly used. Experiments have proved that red maple propagation can use this vegetative rapid propagation method. As long as the growth habits of red maple are satisfied and conditions for rooting are created, the survival rate of its detached materials is at least more than 85%. The key to successful rapid propagation of red maple is to satisfy the requirements of detached materials for full-day light, moisture, temperature, and ventilation, and to adopt a full-sun intelligent seedbed. The rapid propagation survival rate can reach more than 95%. After rooting in rapid propagation, red maple develops relatively quickly, and after hardening off it can be transplanted to the field for rejuvenation cultivation.
III. Rapid propagation of cash crop plants;Many potato diseases use seed potato tubers as the source of infection, and propagation by tubers not only has a low propagation coefficient, but also cannot meet growers' requirements for the supply of good varieties. The use of non-test-tube cloning technology, in addition to a high propagation rate, can also prevent various diseases transmitted by tubers. Especially for black scurf, which is difficult to eradicate with general control methods, disease-free plants can be cultivated by rapid propagation using branches and leaves. There are two technical routes for potato rapid propagation:
1. Stem propagation
Use terminal buds and stem segments for rapid propagation. They can be rapidly propagated directly in an intelligent seedbed of vermiculite or perlite, or the aerial propagation root-promotion method can be used, and after rooting they are transplanted to the substrate, so the survival rate is high and missing plants can be prevented. The method is: in mid-March, plant good seed tubers in a greenhouse; in mid-May, cut terminal buds for rapid propagation, and at the same time promote the production of many lateral buds. When the branches grow to about 10 cm, terminal bud stem segments about 5 cm long can be cut as detached materials for rapid propagation. Under the intelligent seedbed environment, roots can form in one week, planting out can be done in early June, and harvest can be done in 80 days, with a single plant yield of about 600 g.
2. Leaf propagation
     (1) Method of directly producing tubers: that is, not allowing rooting, directly producing tubers, and then using small tubers as seed potatoes. In late January, from mother plants planted in the greenhouse in late November of the previous year, take one-leaf-one-bud materials and inoculate them into a perlite seedbed, bury the axillary buds in the substrate, and leave the leaves on the bed surface. After about 20 days, small tubers form at the leaf axils. This method relies on the nutrients contained in the leaves themselves after being cut from the mother plant and on external light, carbon dioxide, and water to produce tubers. To enlarge the tubers, nutrient solution supplementation must be given to the leaves to increase the nutrients contained in the tubers. This method of directly producing tubers with leaves can also be used for stem propagation, but considering obtaining more detached materials from one stem, the leaf propagation method is more practical.

(2) Method of planting out after rooting: plant the rooted plants directly into the nursery field, and the operation is basically the same as stem propagation. After planting out, the initial growth is later than that of stem propagation, because it has fewer roots and the plant volume is relatively smaller. However, subsequent growth and development are the same as stem propagation, both sending out strong lateral branches from the stem base. Harvest in 80 days, with 4 tubers per plant, about 500 g.
The single plant yield of potato rapid propagation seedlings differs according to the degree of rooting. Those with good rooting survive quickly after planting out, and stem and leaf growth and development are early, with a plant yield reaching more than 600 g. Therefore, to increase the yield of rapid propagation seedlings, striving for more roots and early survival is indeed the key, so combining chemical treatment during rapid propagation has a promoting effect.
Experiments studied the effect of mixed use of different concentrations of naphthaleneacetic acid (NAA), indolebutyric acid (IBA), and gibberellin (GA3) on the survival of potato rapid propagation. The results showed that the treatment with concentrations NAA 50 ppm + IBA 50 ppm + GA3 50 ppm was the best combination, with the highest survival rate, the best rooting, and the strongest growth.
In rapid propagation, whether stem propagation or leaf propagation, within 10-20 days, three situations all appear: first, at the axillary bud site at the base of the detached material only tubers form and no roots; second, both roots and tubers form; third, only roots form and no tubers grow.
The reason these three phenomena occur in detached materials is related to substances such as plant hormones. If the first situation is found during stem propagation, the tuber can be cut off during transplanting, and sometimes roots can still form; when the second situation is encountered, the tuber should also be cut off, and then growth can proceed smoothly. Because netted melon seeds are expensive, in order to reduce seed costs, sowing and seedling raising are carried out in advance. When the melon seedlings grow to a certain height, take one leaf and one bud or leafy melon vines as detached materials, treat the cut with 100 ppm indolebutyric acid for 1 hour, and rapidly propagate in an intelligent seedbed using perlite as the substrate,

generally rooting in 8-9 days. After supplementing nutrient solution to strengthen the seedlings, they can be transplanted and planted out in the field, with a survival rate of 100%. If a clonal rapid propagation system is established and multi-generation cycle technology is adopted, factory seedling production can be carried out year-round, greatly reducing seedling costs. This is currently the lowest-investment factory seedling technique for netted melon. Trial cultivation in 2002 showed that rapid propagation seedlings have uniform growth vigor, and their fruiting traits, yield, and quality are no different from seed-sown seedlings. It is a relatively economical new seedling-raising technique for netted melon planting stock production.
(III) Rapid propagation techniques of cucumber, watermelon, and tomato
These three varieties all belong to the extremely easy-to-root varieties. In the intelligent rapid propagation seedbed, no chemical treatment is needed to achieve a 100% rooting survival rate. During operation, it is only necessary to cut leafy stem vines and rapidly propagate them into a seedbed using perlite as the substrate, and start the system. Generally, roots begin to emerge in 3-4 days, and a well-developed root system forms in 7-10 days, allowing transplanting to the field. Most of these detached materials have already formed root primordia while on the plant, so once they encounter a suitable

environment they immediately form a root system. In the fastest case, such as watermelon, roots emerge the next day. The application of these varieties in production has important value and production significance. The use of multi-generation cycle technology can produce hundreds of thousands or even millions of planting stock from one seed, greatly reducing seed costs. Moreover, the root system of rapid propagation seedlings is more developed than that of seed seedlings, the fruiting and fruit-bearing period is greatly advanced, and both yield and quality are improved. It is an important technique to be popularized and promoted in production in the future.
IV. Rapid propagation of medicinal plants;

Because Medang yew contains extractable anti-cancer drugs, it has become an important medicinal material currently being developed on a large scale across the country. The demand for planting stock is growing. Traditional cutting propagation alone cannot meet production needs, generally producing only one batch per year, while the use of non-test-tube cloning technology can produce at least 5-6 batches, and both the survival rate and seedling quality are greatly improved. More importantly, rapid propagation seedlings can be transplanted year-round, planted out year-round, and developed year-round.

Generally, 3-5 cm long leafy branch segments are taken as detached materials. When materials are scarce, they can be even smaller, even 1-2 cm is acceptable. Treat the cut with 100 ppm indolebutyric acid for 2 hours, and rapidly propagate in a rapid propagation seedbed intelligently controlled by a computer. Callus tissue forms in 7-10 days, rooting begins in 25 days, and hardening off and transplanting can be done in 35-40 days, with a survival rate of more than 90%. In addition, it has been found in production that electric field treatment has an extremely obvious effect on increasing the root-to-shoot ratio, accelerating rooting speed, and cultivating strong seedlings. The application of non-test-tube cloning technology to Medang yew is the most ideal technique for achieving the industrialized development of yew, unmatched by any other method. Honeysuckle has long been a bulk Chinese medicinal material highly valued by the pharmaceutical industry, and is also a daily beverage that can be made into tea. With the deepening of research and development, its uses are becoming broader and broader. Especially after SARS, a boom in developing honeysuckle was set off across the country. Mountain farmers who rely on cultivating honeysuckle to become wealthy and earn foreign exchange have further stimulated their enthusiasm for industrialized development. However, seedling cultivation relying only on grafting and cutting can no longer supply the needs of mountain farmers for developing honeysuckle bases. The use of non-test-tube cloning technology can not only greatly increase the propagation coefficient of traditional honeysuckle varieties that are easy to root by cutting, but also enable the successful rapid propagation of the excellent variety Honeysuckle King, which traditionally can only be cultivated by grafting.
At present, there are many honeysuckle varieties used for production cultivation, most of which belong to varieties easy to rapidly propagate. Generally, without any chemical treatment, an extremely high survival rate can be obtained, and rooting occurs in 10-15 days, with full transplanting and planting out possible in 20-25 days. However, there are also some varieties that cannot survive cutting by traditional methods and can only rely on grafting, and the grafting survival rate is also not high. This may be related to the excessively high chlorogenic acid content in the body of high-yield varieties, and is where the technical difficulty lies in the current difficulty of propagating Honeysuckle King. To address this problem, the propagation system using non-test-tube cloning technology can solve it, and it has now been applied on a large scale in production. The techniques are summarized below:
Honeysuckle King is a variant variety of common honeysuckle, showing extremely high single plant yield, relatively weak growth vigor, and often excessive flower quantity that affects vegetative growth. During rapid propagation, this variety often shows overly developed callus tissue, few and slow roots, and often early leaf shedding during rapid propagation. To address these problems, we conducted a comprehensive analysis and formulated corresponding measures, so that the survival rate of rapid propagation was greatly improved and could basically meet the technical requirements in production. Originally, when Honeysuckle King was grafted, late incompatibility with the rootstock would appear, producing "strangled-neck" seedlings, which are prone to breaking at the graft union in strong winds. This became the main factor limiting the development of this high-yield variety, and traditional cutting cannot survive either. These phenomena indicate that there are genetic differences between this variant variety and the original common variety, which is proved by the grafting incompatibility. In addition, this variety has too many flowers, leading to excessively high chlorogenic acid content in the body, and overly weak growth causes a sharp rise in endogenous abscisic acid content. The combination of these three aspects becomes the comprehensive physiological factors making it difficult to root.

First, in mother stock management, the main management goal should be to cultivate strong seedlings with vigorous vegetative growth. Flower quantity and chlorogenic acid content can be reduced through moderate shading cultivation and applying more nitrogen fertilizer. Flower quantity can also be reduced by spraying 40-100 ppm gibberellin during the flower bud differentiation stage, because the more flowers a plant has, the less nutrient accumulation in the leaves, and at the same time the chlorogenic acid content is also greatly increased. Chlorogenic acid is the main indicator for measuring honeysuckle quality, but it is also the main factor causing the difficulty of propagation and rooting in Honeysuckle King. By reducing light intensity, the chlorogenic acid content in the branches, leaves, and flowers of the plant can be reduced. In addition, applying more nitrogen fertilizer can reduce chlorogenic acid content by 32.99%-6.78%, while applying more phosphorus fertilizer will greatly increase flower quantity and at the same time greatly increase chlorogenic acid content, reaching more than 8.68%-14.44%. These studies show that the mother stock orchard must adopt a management method of applying less phosphorus fertilizer and more nitrogen fertilizer. Such fertilization management measures can also increase endogenous growth hormones in the plant body and lower abscisic acid. Therefore, mother stock management should be exactly opposite to conventional management aimed at production, so as to be more conducive to rooting.

In addition to special management of the mother stock orchard, the problem of early leaf senescence and shedding also appears during rapid propagation. To address this problem, growth hormones can be sprayed on the leaf surface periodically during mother stock management or the rapid propagation period, playing a role in extending leaf age to prevent shedding. Production findings show that detached materials whose leaves remain without falling will sooner or later root, while materials that shed leaves immediately stop developing. When supplementing nutrient solution during rapid propagation, 1-5 ppm indolebutyric acid or 1 ppm sodium nitrophenolate can be added to the nutrient solution, which has a certain effect on extending leaf age and improving survival rate.

After the above comprehensive technical management, rapid propagation operations can be carried out. Take branch segments with 1-2 leaves as detached materials, treat the cut with 200 ppm IBA for 1-2 hours, then rapidly propagate in an intelligent perlite seedbed. In addition to the routine management techniques, it is best to combine carbonated water and oxygen-enriched water supplementation techniques; this measure is especially effective for difficult-to-root plants. In addition, the aerosol method can also be used for rapid propagation, also called the mist multiplication method, exposing the cut to nutrient-containing mist, so rooting is faster. Experiments show that Honeysuckle King propagated in a perlite substrate takes 30-45 days to root, while using aerosol propagation, that is, the mist multiplication method, roots in 22 days, and the survival rate can reach more than 80%. However, aerosol propagation also has a disadvantage: a special hardening-off area still needs to be established for transplanting and hardening off, because most of the roots formed in the mist are aerial roots, and a period of acclimation is still needed to adapt to the soil environment.
Honeysuckle has a wide range of applications, among which making honeysuckle distillate is one of its uses and one of the most widely applied areas. Using plant non-test-tube rapid propagation technology to propagate seedlings has greatly increased honeysuckle yield and also promoted the process of industrialized development of honeysuckle.
V. Rapid propagation of flowering plants;Miniature rose is currently an excellent raw material for mini potted flower production, hydroponic flower production, and test-tube flower production, and is also an excellent variety for courtyard and balcony landscaping and beautification. Besides traditional cutting, the fastest and most efficient method of propagation is the use of non-test-tube rapid propagation technology. It can enable one-leaf-one-bud detached materials to expand into several thousand commercial seedlings in one year through multi-generation cycle technology, and the operation is simple and convenient, with short rooting time and high survival rate. Take a leafy branch segment, one leaf and one bud, or a terminal shoot with flower buds from a miniature rose plant as detached material, treat the cut with 100 ppm IBA for 1-2 hours, and rapidly propagate in an intelligent seedbed using perlite as the substrate. Under normal conditions, rooting begins in 7-10 days, and transplanting can be done in 15-20 days, with a rooting survival rate of more than 95%. Using miniature rose as material for rapid propagation of small materials with buds, after rooting, inoculate them into an agar substrate environment in a test tube to grow, thus making a test-tube rose that can grow and bloom in a test tube. It is currently a premium product among test-tube flowers at home and abroad, and also the best gift for Valentine's Day.

(1) Stem-cutting induction method: Phalaenopsis is a monopodial plant, growing upward from an upright stem and continuing without end. Although there are 1-3 latent buds at the leaf axil stem base, most cannot sprout into plants. However, after the plant grows larger, one can cut between the clustered roots below the clustered leaves with a sterilized knife or scissors. The upper part with roots is planted into a new pot or temporarily planted, so that it continues to grow, while the lower part retaining the rhizome is given appropriate water, and before long 1-3 new buds can sprout (depending on plant characteristics and management methods). If the stem is too long, it can also be cut into multiple segments; as long as each segment is 3 cm or more and has more than one root, each node can send out 1-2 buds. Cut off the small buds with a blade and propagate them in an intelligent seedbed. Generally, they can root and be transplanted in 10-15 days.
(2) Chemical stimulation method: this chemical is available for sale in flower markets. Its main component is cytokinin, and it is in an oily waxy form. When using it, dip a toothpick into the agent and smear it on the dormant bud points. The chemical can then penetrate and stimulate sprouting. When the bud body grows out smoothly, it can be cut off for rapid propagation.
(3) Flower stalk tiller buds: many varieties of Phalaenopsis have the habit of sprouting tiller buds at the base of the flower stalk, at non-flowering stalk nodes, and at the tip. Native species such as P. lueddemanniana, P. schillerana, P. equestris, etc., after tiller buds sprout at the very front end of the flower stalk, are cut off and propagated in an intelligent seedbed; after they grow and root, they can be transplanted to become new individuals. If the variety has no stalk tillering habit, a sprouting agent containing plant hormones can be smeared on the nodes of the Phalaenopsis flower stalk, using chemical stimulation to achieve the purpose of propagating new seedlings. Before smearing the agent, first remove the bracts covering the flower stalk nodes with a blade. When removing the bracts, care must be taken to avoid breaking the bud body. After the bracts are removed, smear the sprouting agent. When using a plant hormone sprouting agent, it is best to do so during the plant's growing period, and the effect is better when the temperature is above 20°C.
VI. Rapid propagation of economic forest plants;Camellia oleifera is an important oil plant and also an important economic plant for mountain farmers. However, long-term seed sowing for seedling raising has caused mixed varieties, severe degeneration, decreased yield, and late fruiting, greatly affecting the industrialized development of Camellia oleifera.
Under facility greenhouse conditions, year-round rapid propagation and multi-generation cycling of Camellia oleifera can be implemented, with relatively high production efficiency and relatively guaranteed rooting survival rate, unmatched by other grafting and cutting methods. It is an indispensable new planting stock cultivation technique for the current industrialized development of Camellia oleifera. The technical points are introduced below: detached materials should be selected from 1-year-old robust, already lignified, plump-axillary-bud, intact-leaf, pest- and disease-free branches on excellent mother trees, cut into detached materials about 4 cm long with one bud and one leaf. Material collection should preferably be done in the early morning. After collection, bundle the detached materials in groups of 50-100 and pay attention to moisture retention. Before rapid propagation, treat the detached materials with ABT rooting powder to promote cut healing and rapid rooting. During rapid propagation, the detached materials should be inoculated upright, with buds and leaves exposed above the substrate, leaf surfaces facing upward, and a spacing of about 5 cm x 15 cm, with leaves not overlapping as the criterion. After inoculation is completed, immediately start the intelligent system.
Practice has shown that treating Camellia oleifera detached materials with ABT No. 1 rooting powder results in a survival rate and current-year sprouting rate significantly higher than treatment with 200 ppm naphthaleneacetic acid; the number of roots and root length are also greater and longer than with naphthaleneacetic acid treatment. The survival rate can reach more than 85%. After adopting the multi-generation cycle technology of propagating seedlings from seedlings, the survival rate can be further increased and the rooting time further shortened. Usually, for first-generation seedlings, callus tissue forms in 10-15 days, root primordia form in 20-25 days, and root systems form and are transplanted to the field in 30-45 days. If the operation of propagating seedlings from seedlings is adopted, juvenility and rooting genes will be activated, and the rooting time can be shortened to 20-25 days, with higher efficiency and greater speed. Therefore, when rapidly propagating Camellia oleifera seedlings, the construction of a juvenilized mother stock orchard is extremely important.

In addition, when treating with the agent, it is better to use a high concentration of ABT No. 1 for quick dipping, as this gives high operational efficiency and a good survival rate. Comparing the high-concentration ABT No. 1 rooting powder quick-dip method with the low-concentration slow-soak method, the former is superior to the latter in survival rate and number of roots; the best combined treatment is ABT No. 1 at a concentration of 500 ppm, quickly dipped for 10 seconds and then rapidly propagated. When ABT No. 2 rooting powder was used to treat detached camellia oleifera material, its survival rate and root number were also superior to the effects of treatment with 200 ppm naphthalene acetic acid. Comparing the quick-dip method with the slow-soak method, the high-concentration quick dip is also more effective than the low-concentration agent slow soak. For ABT rooting powder, a 200 ppm concentration solution, quickly dipped for 20 seconds, is best. Comparing ABT No. 1 rooting powder with ABT No. 2 rooting powder, the survival rate of camellia oleifera detached material treated with ABT No. 1 is clearly higher than with 200 ppm ABT No. 2, but the effect produced by the same concentration of ABT No. 2 differs from the effect of naphthalene acetic acid treatment, not reaching a significant level; therefore, all things considered, for non-test-tube cloning propagation of camellia oleifera, ABT No. 1 rooting powder should be selected, and the higher concentration (500 ppm) quick-dip method should be used.
II. Applications of Camellia oleifera
Honghua Daguo camellia oleifera is an evergreen small tree of the Theaceae family, with a tree height of 3-6 m. It is a rare and precious woody oil tree; the camellia oil is orange-yellow, clear and transparent in color, and fragrant in smell, contains more unsaturated fatty acids than peanut oil and rapeseed oil, and contains no erucic acid. Behenic acid and aflatoxin and other carcinogenic substances. Regularly eating camellia oil can lower the body's blood lipids and cholesterol levels, and has preventive and therapeutic effects on diseases such as high blood pressure, stroke, cerebral thrombosis and cancer; it is a purely natural green health edible oil of good quality.
For example, the recently very popular Tibetan secret slimming camellia tea is one of the applications of camellia oleifera; it fully reflects the position of camellia oleifera applications in the market, and has also strongly developed the role of camellia oleifera as an economic crop.
VII. Rapid propagation of endangered plant species;Baishanzu fir is a rare plant that is endangered and extinct in the wild; because traditional propagation methods give a very low survival rate, it has always been a major technical problem for forestry workers seeking to save this germplasm resource. However, using plant non-test-tube cloning technology can achieve a fairly high survival rate. The relevant technique is briefly introduced as follows: detached material comes from Baishanzu, Qingyuan County, Zhejiang Province; the detached material is cut into leafy branch segments 3-5 cm long, and the cut ends are treated with 1000 ppm indolebutyric acid for 8-10 hours, then propagated in an intelligent seedling bed. According to observation, after 25-30 days the cortex swells and begins to form callus tissue, after 45 days some have papilla-like root primordia growing out, and after 60-70 days most have grown roots 1-2 cm long, with a checked survival rate of over 90%.

Golden camellia contains natural organic germanium, selenium, manganese, molybdenum, vanadium, zinc and more than ten other trace elements with important health value for the human body, as well as tea polyphenols, and essential amino acids for the human body; it has health functions such as preventing cancer, inhibiting tumor growth, lowering blood cholesterol, lowering cholesterol, preventing atherosclerosis, delaying aging and improving the body's immune function, and is a health drink raw material plant with great development value. In addition, the flowers of golden camellia are waxy golden yellow, with golden petals and jade stamens, fresh and delicate, dotted among green leaves and fine branches, with a graceful bearing; it is known as the "superstar" among flowers, the "queen of the tea family" and the "giant panda" of the plant world, and is a national first-class protected rare plant. Besides having extremely high ornamental value, golden camellia is the finest among camellias.

Guangxi golden camellia is a first-class protected plant, and rapid propagation trials were carried out on golden camellia and Camellia liberofilamenta. For the former, treated with rooting powder (ABT) No. 1 at 200 ppm, 1-year-old detached material on perlite substrate had a survival rate of 0 for cuttings without leaves, a survival rate of 85.0%-87.8% with 1 leaf, and 72.0% for the control; the survival rate for 2-year-old material was 20.5%. For the latter, on perlite substrate, treated with rooting powder No. 1 at 150 ppm, 1-year-old detached material on perlite had the highest survival rate, 97.5%. Therefore, in production it is recommended to use 1-year-old seedlings as mother plants and carry out multi-generation cyclic multiplication by propagating seedlings from seedlings, which can achieve good seedling-raising results.

Brief Introduction to Plant Rapid Propagation Technology

The so-called plant non-test-tube efficient rapid propagation technology is also plant cloning technology; some people also call it plant non-test-tube rapid propagation technology, plant rapid propagation technology, plant full-light mist propagation technology, full-light mist cutting technology, micro-material or micro-tissue cutting propagation technology, mist propagation technology, mist cutting propagation technology, and foolproof cloning. Whether it is called plant rapid propagation or plant cloning, its principles and methods are the same.

The key to plant cloning technology (plant rapid propagation technology) is misting. More than ten years ago, authoritative units were already promoting full-light mist propagation technology, which is actually what later some people called plant non-test-tube efficient rapid propagation technology, and what is now more often called by fashionable terms such as plant cloning and foolproof cloning. The complete misting equipment developed in the past was mechanical, with a cost as high as tens of thousands of yuan, and it rusted and damaged easily, so after a period of time no one used it anymore. However, since the introduction of Israeli micro-mist (nozzle) technology, the micro-misting problem was smoothly solved in a low-cost form, and thus plant cloning technology (plant rapid propagation technology) was rapidly promoted and popularized across the country.

Another obstacle to the promotion of plant rapid propagation technology (plant cloning technology) was the problem of automatic controllers. Imported temperature and humidity control equipment is easy to use but expensive; the so-called agricultural intelligent computer systems, besides being even more expensive, are always immature, with problems emerging one after another in use, often causing seedling-raising failures. Only after using them for two years did the author have no choice but to develop a domestically produced seedling-raising instrument, whose low price and rich, practical functions were quickly appreciated by peers nationwide.

The current investment in plant cloning technology (plant non-test-tube efficient rapid propagation technology) is only a bit more than 2000 yuan; vigorously promoting plant cloning technology and plant rapid propagation technology benefits the country and the people.

Compared with plant tissue culture test-tube rapid propagation and traditional seedling-raising technology, plant foolproof cloning technology has the following advanced features:

1. Using one-leaf-one-bud plant explants as the propagation unit material, directly inoculated in field sand beds or nutrient bags, forming seedlings in one step until supplied to production, without any need for movement, and with a high survival rate.

2. Whether in the south or the north, at different latitudes, in different soils and different climates, this method can be used for continuous rapid propagation all year round, and from the second generation onward most varieties can reach 6-12 generations. On any of the 365 days of the year, this rapid propagation technology can be used to start production, expanding the time and space for technology application.

3. The technical operation is easy to promote. After a period of training, qualified ordinary laborers can inoculate 3000-5000 unit materials per day (8 hours). Long-term promotion practice proves: first, the requirements for the quality of production technical personnel are not high, the technical training period is short, adaptability is extremely broad, and it is easy to promote; second, the personal operation speed is faster than both tissue culture rapid propagation and conventional seedling raising. If organization and management are proper, and other conditions are met, each base can rapidly inoculate 200,000-1,000,000 unit propagation materials per day, and the technology is easy to promote on a large scale, which test-tube rapid propagation technology cannot match.

  4. Ordinary personnel who have undergone a period of planned training can participate in rapid propagation operations, and the inoculation speed is extremely fast (several times faster than tissue culture test-tube rapid propagation inoculation speed; from the second generation onward, most plants exceed both the conventional seedling-raising operation speed and the test-tube rapid propagation operation speed. This greatly saves labor costs and improves labor efficiency).

      5. Each technically qualified worker who has undergone a period of training can produce and manage 20,000-100,000 seedlings per month, and each core worker plus a certain number of auxiliary workers can produce at least 300,000 young seedlings every half year, creating extremely high economic benefits.

6. For most plants, after being cultured to the second generation or later using plant foolproof cloning technology, complete regenerated plants can be obtained in 4-11 days, with a regenerated plant rate of over 90%, truly achieving efficient rapid propagation. Some families and genera have special rooting and propagation conditions, such as chicken-feather podocarpus, spruce, yew, camphor oil tree, rock osmanthus, Chinese orchid, peony and others, whose rooting lasts a relatively long time. But they are still faster than test-tube rapid propagation and conventional seedling raising, and the comprehensive rapid propagation efficiency is higher.

7. For most plants, from the second generation onward, each regenerated plant propagates one generation every 30-60 days, with a multiplication coefficient of 2-15 times per generation (efficient geometric multiplication based on the original plant quantity base). This advantage is even more prominent than that of tissue culture test-tube rapid propagation. The later the generation, the more germplasm resource materials are propagated, and the faster the propagation speed.

      8. There are few technical steps and the time used is short, greatly saving comprehensive production costs and improving personnel production efficiency. Starting propagation from micro-material can directly cultivate plants that grow under natural conditions, without any transplanting; for most plants, only 15-60 days of cultivation are needed before they can be used for production cultivation, and the plants all show early flowering and fruiting and good yield performance. (For example, tomato begins rooting in 4 days, flowers and fruits in 20 days; goji blooms and fruits in the nursery plot in the same year; virus-free potato one-leaf-one-bud material can differentiate small tubers from inoculation to 40 days, and when cultivated in the same year can directly harvest large virus-free potatoes in the field. The field yield of virus-free potato seedlings in the same year can reach 3 to 4 tons, which not only saves farmers 300 jin of seed potatoes per mu, but also allows farmers to plant original seed potatoes every year. Cut-flower rose does not need transplanting; from inoculating one leaf it flowers in 70 days, with large and bright flowers, and the flowering cycle is longer than with plants cultivated by other methods. Coniferous tree species such as yew, North American redwood, western Sichuan spruce, Japanese larch and others generally need 4 months for planting out on the mountain. The first generation generally begins rooting in 20-40 days, and after the second generation the rooting time is shortened by about one third. However, many plants among coniferous tree species are very difficult to tissue culture and basically cannot be produced on a large scale. Conventional cuttings also have slow rooting and low survival rates. As a result, seedlings of these varieties have always been propagated by seed, and the traits of the offspring vary greatly.

9. Mature seedlings cultivated by this method have high purity, no pests or diseases, well-developed and complete root systems, root length over 25 cm, 3-6 roots, plump mature buds, and stem height 20-60 cm; the survival rate when planted out in production fields is over 90%. For coniferous tree species, 5 cm-15 cm, and the survival rate for planting out on the mountain is generally as high as over 95%.

10. Green seedlings directly inoculated and cultured in nutrient bags during the plant growing season have high purity, no pests or diseases, have grown more than 3-5 leaves, have plump axillary buds, strong branching ability, well-developed root systems, and high seedling-hardening quality; the survival rate when planted out in production fields reaches over 95%.

11. For many plants, the first generation is already normal. Large-scale rapid propagation production can be carried out immediately. But some difficult-to-propagate plants can only reach the indicators required by this technology from the second generation. For these seedlings, the main goal pursued in the first generation is to obtain as many original basic seedlings as possible, laying a good foundation for normal production from the second generation onward. Plant foolproof cloning technology can be used for the vast majority of plants that can be propagated by plant tissue culture shoot-tip rapid propagation and conventional cutting seedling-raising technology, or plants for which neither of the above two technologies is suitable for propagation; it can be used to fix heterosis in plant breeding work; it can be used for special transgenic plant seedling engineering, new plants from space breeding, various new germplasm materials or the rapid propagation, promotion and protection of endangered economic plants, forest tree seedling raising, seed engineering and seed industrialization; it can be used for the selection, purification and large-scale production and utilization of natural mutant plants, superior individual plants and polyploid superior clones; it can be used for isolated expansion and propagation of virus-free original seedlings; it can be used for the introduction and diffusion of new varieties at home and abroad, crossbreeding, and so on. In these aspects, this technology has the optimality of technology and the relative infinitude of the market.