CN112293077A

CN112293077A - Method for shortening breeding years of chimonanthus nitens

Info

Publication number: CN112293077A
Application number: CN202011254492.9A
Authority: CN
Inventors: 宋兴荣; 袁蒲英
Original assignee: Horticulture Research Institute of Sichuan Academy of Agricultural Sciences
Current assignee: Horticulture Research Institute of Sichuan Academy of Agricultural Sciences
Priority date: 2020-11-11
Filing date: 2020-11-11
Publication date: 2021-02-02

Abstract

The invention discloses a method for shortening the breeding period of wintersweet, which comprises the following steps of (1) sowing seeds in time after harvesting in early summer; (2) sowing and seedling management; (3) grafting high branches; (4) dwarfing and promoting flower growth. The invention can effectively shorten the breeding period of the wintersweet by more than 2 years through the comprehensive innovative integration technology of 'random seeding, high branch grafting and dwarfing flower promotion', wherein the time of 1 year is saved by the random seeding compared with the traditional spring seeding in the next year, the branch high branch of the 1.5-year-old seeding seedling is grafted on the mature sound plant to promote early flowering and shorten the breeding period by 1-2 years, the dwarfing flower promotion further ensures the flowering rate of the current-year-old grafting plant, the observation time of the characteristics of the flower part can be effectively ensured and early, the comprehensive innovative integration technology reduces the management and protection cost and the occupation time of the land, improves the resource utilization rate, greatly reduces the breeding cost and promotes the breeding process.

Description

Method for shortening breeding years of chimonanthus nitens

Technical Field

The invention relates to the technical field of forest tree breeding, in particular to a method for shortening the breeding period of chimonanthus nitens.

Background

The wintersweet is used as a unique traditional rare ornamental flower and tree in the country of origin, has the advantages of luxuriant branches and leaves, strong cold resistance, drought resistance, slight shade resistance, strong growth vigor and branch development force, cold and irritability in flowers in winter and spring, unique wind posture, strong fragrance and unique lasting appeal, has the functions of greening, beautifying, colorizing, water and soil conservation and environment and air purification, is an indispensable tree species for environmental creation, greening of industrial and mining enterprises, returning to forest and the like, is also an excellent material for fresh cut flowers, bonsais and the like, and can be used as a medicine for roots, stems, leaves, flowers, fruits and buds. The wintersweet flower has unique fragrance components, can be used for extracting essence and scenting tea, and can be made into wintersweet beverages, wintersweet foods, dishes, dried wintersweet flowers, biopharmaceuticals, wintersweet pesticides and the like, has extremely high ornamental and economic values, and is popular with people.

In the traditional breeding work, the time from sowing to flowering of the wintersweet is usually 3-4 years, the flowering quantity is extremely small due to the beginning of flowering, and the flowering characters in the first two years are not stable enough, so that the flowering characters in 5-6 years basically reach the full-bloom stage and can be observed and recorded after the characters of the flower parts are stable, the variety characteristics are really reflected, then, 1-2 years are needed for finding excellent single plants, the regional test is at least more than 3 years, the breeding period is long, and the shortest time of breeding a new variety is about 10 years. The breeding period is long, and the breeding of good varieties and the coping and adjustment of market demands are not facilitated.

Therefore, the problem to be solved by the technical personnel in the field is to provide a breeding method of Chimonanthus nitens with short breeding period.

Disclosure of Invention

In view of the above, the invention provides a method for shortening the breeding period of chimonanthus nitens, which can effectively shorten the breeding period by more than 2 years, greatly reduce the breeding cost and save the land.

In order to achieve the purpose, the invention adopts the following technical scheme:

a method for shortening the breeding age of Chimonanthus nitens comprises the following steps:

(1) seed harvesting and processing: collecting seeds when the wintersweet fruit tray is changed from green to light yellow brown and begins to shrink, and sowing in time within 2 days after the seeds are stripped;

or immediately mutagenizing after stripping the seeds and sowing in time;

or stripping off seeds, refrigerating at 2-4 deg.C, and sowing within 7 days or performing mutagenesis treatment and sowing;

(2) sowing and seedling management: sowing by dibbling or drilling, covering soil of 4-5cm after sowing, covering sun with a sunshade net after watering thoroughly, and germinating 5-7 days later and basically completely after half a month later; after 3-4 pairs of true leaves grow out, performing pest and disease damage, grass, fertilizer and water management, removing the sunshade net in 10 months, and culturing for 1.5 years to obtain seedlings to be grafted;

(3) high branch grafting: grafting the seedling to be grafted on a tender wintersweet stock which is generated in 8-10 years by a high branch grafting method by adopting a cutting method when the average temperature is 15-20 ℃ before the bud germinates in the next spring in the middle and last ten days of 10 months;

(4) dwarfing and flower promoting: grafted new buds growing to 5-10cm in the step (3), and applying PP to roots₃₃₃Or spraying on leaf surfaces B₉。

The invention can effectively shorten the breeding period of the wintersweet by more than 2 years through the comprehensive innovative integration technology of 'random seeding, high branch grafting and dwarfing flower promotion', wherein the time of 1 year is saved by the random seeding compared with the traditional spring seeding in the next year, the branch high branch of the 1.5-year-old seeding seedling is grafted on the mature sound plant to promote early flowering and shorten the breeding period by 1-2 years, the dwarfing flower promotion further ensures the flowering rate of the current-year-old grafting plant, the observation time of the characteristics of the flower part can be effectively ensured and early, the comprehensive innovative integration technology reduces the management and protection cost and the occupation time of the land, improves the resource utilization rate, greatly reduces the breeding cost and promotes the breeding process.

In the middle ten days of 6 months, the wintersweet seeds are just ripe, the fruit bases are changed from green to light yellow brown and the seeds are harvested when the fruit bases shrink, at the moment, the water content of the seeds is high, the seeds can be sown without soaking, and compared with the conventional spring sowing seeds, the spring sowing seeds have high emergence rate and quick germination; seedling emergence is carried out 5-7 days after sowing, the full stage of seedling emergence can be reached 7-10 days, seedling emergence is basically completed in 15 days, and the final seedling emergence rate is more than 90%; the sowing time of the sowing in the following-up sowing mode is improved by 9 months compared with that of the sowing in 3 months in next spring, in addition, the seedling emergence in spring sowing is slow, the seedling emergence period is long, when the seedling height of the seedling in the year is slightly higher than that of the seedling in autumn, the difference between the plant height of the seedling in the 6 months in the year and that of the seedling in the 3 months in the next year is not large, so that the time of 1 year is almost saved compared with that of the traditional spring sowing in the following-up sowing mode, and the method is favorable for.

After sowing, the seedlings are covered by a sunshade net, so that the soil moisture and the temperature and the humidity of the seedbed are kept suitable, the seedlings are prevented from being burnt in summer, and meanwhile, the plants can grow due to moderate shading in the seedling stage. Conventional pest and disease damage, grass, fertilizer and water management provides nutrients and water required for growth of the seedlings of the Chimonanthus praecox, and ensures that 1.5-year-old Chimonanthus praecox reaches the scion standard, the plant height of the Chimonanthus praecox reaches 85-120cm, the ground diameter reaches 1-1.5cm, and the stem thickness reaches 0.8-1.2 cm.

In the high branch grafting step, the old healthy and strong waxberry trees which grow for 8-10 years are selected as the stocks, the stocks are sufficient in nutrition and strong in growth potential, and the early blooming of grafted branches is facilitated.

After high branch grafting, because the number of branches, the branch length, the tree body and the like after short cutting are obviously less or smaller than the original ones, the grafted branches are usually over-nourished, grow extremely fast and vigorously, in order to ensure the flowering rate of the current-year grafted plants, the grafted seedlings are subjected to hormone treatment (root application or foliage spraying), the growth vigor of the treated plants is slowed down, the branches are thick and strong, the leaf color is dark green, internodes are shortened, the wind resistance is enhanced, the vegetative growth is controlled to a certain degree, the reproductive growth is accelerated, and the formation of flower buds and the flowering promotion are facilitated.

As a preferred technical scheme, soil preparation is carried out before sowing: selecting a land block which is leeward and sunny, has smooth land, convenient irrigation and drainage, deep soil layer and loose and fertile soil; deep ploughing and harrowing are carried out before sowing, the ploughing depth is more than or equal to 20cm, and stones and weeds are removed; making a furrow with width of 1-1.2m and height of 30cm, and sterilizing with 1% potassium permanganate or 800 times carbendazim.

The technical scheme has the beneficial effects that fertile soil is selected, stones and weeds are removed, and the wintersweet seed germination and growth are facilitated.

As a preferable technical scheme, the seeding row spacing in the step (2) is 20-30 cm; the distance between plants of the non-mutagenized seeds is controlled to be 8-10cm, and the distance between plants of the mutagenized seeds is controlled to be 4-5 cm.

The technical scheme has the advantages that the seed germination rate of radiation or chemical mutagenesis is low, and the plant spacing is reduced to avoid excessive empty seedlings and waste of land resources.

As a preferable technical proposal, the growth period of the step (2) is 20-25g/m per month²Applying urea or compound fertilizer for 1 time, and applying phosphorus-potassium fertilizer for 1 time in 10 months.

The technical scheme has the beneficial effects of ensuring nutrients required by growth of the wintersweet plants, increasing the cold resistance and freezing resistance, and ensuring that 1.5-year-old seedlings of the wintersweet meet the scion standard.

As a preferable technical scheme, the sunshade net in the step (2) is a sunshade net with 50% shading degree.

As a preferable technical scheme, the thickness of the stem of the seedling to be grafted in the step (2) is 0.8-1.2 cm.

As a preferred technical scheme, in the step (3), the wintersweet rootstock is cut short at a height of 40-80cm from the ground, the thin stem is properly kept low, the thick stem is properly kept high, and the side of the rootstock is longitudinally cut to 2-3cm and is deep to xylem; selecting the branches of the seedlings to be grafted in the step (2) as scion branches, reserving 1-2 pairs of buds of the scion, cutting the scion into a flat wedge shape with the length of 3-5cm, inserting the cut scion into a stock cut to be aligned with a cambium on one side, tightly binding and sealing the stock and the stock cut by using a fixing band after the two are tightly connected;

the stem thickness of the wintersweet rootstock is 3-5 cm; the fixing band is a plastic band.

The technical scheme has the beneficial effects that 8-10-year-old flowering waxberry trees with stems 3-5cm thick are selected as the stocks and are cut short at a height of 40-80cm from the ground. If the stem is too thin, the nutrient supply after grafting is often insufficient, the growth vigor of the plant is slow, and the flowering is influenced to a certain extent; if the plant is too thick, the tree age of the plant is too big, the grafting survival rate is influenced, and part of the plant also influences the growth vigor of the plant; too low short cut of the stock easily causes too concentrated nutrients and excessively long grafted branches, and branches are easily blown off by wind or are difficult to flower in the current year when the vegetative growth is too vigorous; and the short cut of the rootstock is too high, so that the nutrient supply is insufficient and the growth of the branch is slow.

As a preferred technical scheme, the high branch grafting in the step (3) can be carried out in the middle and late 10 months and before the next spring bud germinates, and the average temperature can be 15-20 ℃. Preferably, the bud germination in spring is expanded to 0.3-0.5 cm.

The technical scheme has the beneficial effects that the optimal grafting time is usually only 7-10 days when the bud sprouts in spring expand to 0.3-0.5cm, the plants begin to recover the vitality, the sap starts to move, the buds sprout quickly, and the grafting survival rate is high. Grafting before germination in autumn, winter and early spring in other times has more selection opportunities, is convenient to arrange or is not easy to miss, and has relatively high grafting survival rate, so the grafting method is also commonly adopted.

As a preferred technical scheme, when grafting in autumn and winter, the method also comprises the step of sleeving a transparent heat preservation bag on the grafting part in the step (3), and after the grafted seedling grows out a new bud, removing the heat preservation bag.

The beneficial effects of above technical scheme are that, the insulated bag can play the effect of heat preservation and moisturizing, is favorable to the healing of grafting position wound and prevents the scion dehydration to improve the grafting survival rate.

As a preferred embodiment of the present invention, the PP of the step (4)₃₃₃The concentration is 1000mg.L^-1The application amount of each plant is 0.5-1.0L; b is₉The concentration is 1500mg.L^-1The spraying amount is determined by the spraying humidity of both the front and back surfaces of the leaves.

The technical scheme has the beneficial effects that the growth vigor of plants is slowed down, branches are thick and strong, the leaf color is dark green, internodes are shortened, the wind resistance is enhanced, the vegetative growth is controlled to a certain degree, the reproductive growth is accelerated, the formation of flower buds and the flowering promotion are facilitated, the flowering quantity in the same year is obviously increased, the flowering rates of different varieties are improved by 10-40% and are unequal, the flowering rates of most varieties reach 30-60%, partial varieties reach 90-100%, and the flowering characters are not influenced, so that the advanced observation on the character characteristics of the flower parts is facilitated, and the breeding period is shortened.

As a preferable embodiment of the present invention, the step (4) further includes: after the grafted seedling in the step (3) grows new buds, removing all buds and corktree sprouts of the stock; when the grafted sprout grows to 5-8cm, loosening the tied plastic binding belt or cutting off part of the plastic binding belt; removing all binding plastic belts when the grafted sprout grows to be more than 30cm, and well performing support protection work of the grafted sprout, or limiting the growth of the grafted sprout by pinching to avoid being blown off by wind; the rest is the same as the conventional maintenance management.

The technical scheme has the advantages that after grafting, when the sprouts grow to 5-8cm, the tied binding plastic bands or the cut binding bands are slightly loosened, so that the free growth of callus at the joints is facilitated, poor healing at the joints caused by the fact that the callus grows due to the limitation of over-tightening of the binding bands is avoided, and the grafted branches are prone to fracture in the future. And removing all binding plastic belts when the grafted buds grow to be more than 30cm, inserting a bamboo pole or a branch, lightly tying the grafted branches on the pole by using the plastic belts, and performing support protection work of the grafted branches, or limiting the growth of the grafted branches by pinching to avoid being blown off by wind.

The invention also aims to provide the application of the method for shortening the breeding age of the chimonanthus nitens in seedling selection, cross breeding and mutation breeding.

According to the technical scheme, compared with the prior art, the method for shortening the breeding period of the wintersweet is disclosed, the breeding period can be effectively shortened by more than 2 years through the combined innovative integration technology of 'random seeding, high branch grafting and dwarfing flower promotion', wherein the time of about 1 year is saved in the random seeding compared with the traditional spring seeding in the next year, the high branch of the 1.5-year-old seeding seedling is grafted on a mature sound plant to promote early flowering, the breeding period can be shortened by 1-2 years, the dwarfing flower promotion further ensures the flowering rate of the current-year grafted plant, the observation time of the characteristics of the flower part can be effectively ensured and early, the combined innovative integration technology reduces the breeding management and protection cost and the occupation time of the land, the resource utilization rate is improved, the breeding cost is greatly reduced, and the breeding process is promoted.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the provided drawings without creative efforts.

FIG. 1 is a schematic diagram of high shoot grafting and dwarfing flower-promoting plant flowering in example 2 of the present invention.

Fig. 2 is a schematic diagram of spring sowing in embodiment 1 of the present invention.

FIG. 3 is a schematic diagram of high branch grafting according to embodiment 2 of the present invention.

FIG. 4 is a schematic diagram of the embodiment 2 of the invention after high branch grafting.

FIG. 5 is a schematic diagram of a growth period after high branch grafting according to embodiment 2 of the present invention.

FIG. 6 is a schematic view showing that the grafted branches after the high branch grafting are broken by wind without being supported and protected.

FIG. 7 is a schematic diagram showing flowering of the high shoot grafted and non-hormone-treated strain in example 2 of the present invention.

FIG. 8 is a schematic diagram of high shoot grafting and dwarfing flower-promoting plant flowering in example 2 of the present invention.

FIG. 9 is a schematic diagram showing flowering of the high shoot grafted and non-hormone-treated strain in example 3 of the present invention.

FIG. 10 is a schematic diagram of high shoot grafting and dwarfing flower-promoting plant flowering in example 3 of the present invention.

FIG. 11 is a photograph showing the result of the example 2 ' fairy shoot tip being proved by ' fine breed '.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The embodiment of the invention discloses a method for shortening the breeding period of chimonanthus nitens, materials and reagents related in the invention are commercially available, the sources of the materials and the reagents are not specifically limited, and the methods which are not mentioned are all conventional operations and are not described in detail herein.

Example 1

Comparison of seeding methods for 'starlight-brilliant' varieties

(1) Nursery selection and preparation: selecting a land block which is leeward and sunny, has flat land, convenient irrigation and drainage, deep soil layer and loose and fertile soil. Deep ploughing and harrowing are carried out before sowing, the ploughing depth is more than or equal to 20cm, and stones and weeds are removed. Making ridges with width of 1-1.2m and height of 30cm, and covering with 1% potassium permanganate or 800 times carbendazim film for sterilization for 7 days. And airing for 2 weeks for later use.

(2) Seed harvesting and processing: and 6, 15 days in 2011, harvesting the 'tip-covered' wintersweet fruit tray, wherein the fruit tray just changes from green to light yellow brown and begins to shrink, and immediately stripping off the seeds for sowing.

(3) Sowing (simultaneously setting a spring sowing comparison example):

adopting the following steps: directly sowing the seeds stripped in a seedbed prepared in advance in 16 days 6 months in 2011 at row spacing of 20-30cm and plant spacing of 8-10cm, covering soil of 4-5cm after sowing, watering, building a shade shed, and covering with a 50% sunshade net.

Adopting a spring sowing mode: the seeds sowed in spring have hard and thick seed coats and are not easy to bud, water separation is firstly carried out, then warm water of about 50 is used for soaking for 3-5 days, water is frequently changed, the seeds are continuously kneaded by hands before water is changed every time, and sowing is carried out after most of the seed coats are softened. And 3, 11 days in 2012, sowing according to the row spacing of 20-30cm and the plant spacing of 8-10cm, covering soil of 4-5cm after sowing, building a shed after watering thoroughly, and covering with a 50% sunshade net. (see FIG. 2)

(4) And (3) management of the seeding:

the seedlings grow slowly after emergence, when the seedlings grow 3-4 pairs of true leaves, the pest control, weeding, soil loosening and fertilizer and water management are carried out regularly, the soil is kept moist at any time in the seedling stage, the rapid growth of the seedlings is facilitated, and the growth period is 20-25g/m per month²Applying urea or compound fertilizer for 1 time to ensure the nutrients needed by growth. In rainy season, the plants are prevented from dying due to accumulated water by paying attention to drainage and waterlogging prevention.

(5) High branch grafting

And (3) highly grafting the 1.5-year-old young seedling branches on middle-aged and young-aged mature plants. A cutting grafting method is adopted, grafting time is 11 months and 2 days in 2012, seeding strong seedlings which grow strongly and well in 1.5 years, have good development, no plant diseases and insect pests, short internodes and full development in 'starlight brilliant' varieties are selected as scion branches, stock is selected to grow healthy and rich 8-year-old flowering waxberry trees, and the stem thickness is 3-4 cm. The stock is cut at a position 50-70cm away from the ground, and 2-3cm is longitudinally cut at the smooth side of the stock to reach the xylem, and the section is smooth; 1-2 pairs of buds of the scion are reserved, the scion is 3-5cm long, the lower part of the scion is cut into a flat wedge shape, a xylem is slightly formed, and a cambium is exposed; and inserting the cut scion into the cut of the stock, aligning the cut scion with a cambium on one side, tightly binding and sealing the stock and the cut scion by using a plastic tape after the cut scion and the cambium are tightly connected, and then bagging, preserving heat and moisturizing.

(6) Managing and dwarfing and promoting flowers after grafting (setting a hormone-free treatment comparative example of the grafted seedling at the same time):

after the grafting survives and grows new buds in the middle ten days of 3 months, firstly breaking a plurality of holes of the sleeve bag to be communicated with the outside air, gradually removing the sleeve bag after 2-3 days, removing the cork trees which sprout on the rootstock, and cutting without bumping the scion. When the sprouts are about 5cm long in late 3 months, slightly loosening the tied binding plastic belts or cutting off the binding belts to facilitate the free growth of the calluses at the joints; when the new branch grows to be more than 30cm, the wound is basically healed, all binding plastic belts are removed, and the branch or the small bamboo pole and the like are used for supporting and protecting the grafted branch so as to prevent the grafted branch from being blown off by wind. And other operations such as watering, fertilizing, weeding, soil plowing and the like are performed with normal maintenance management.

Wherein, when the grafted sprout grows to about 10cm, 0.8L 1000mg.L is applied to the root^-1PP₃₃₃。

(7) Statistics of results

A. Statistics of growth conditions of seedlings sowed at random and in spring

The seedling emergence rate is high and the germination is fast when the seedlings are picked and sown, the seedlings emerge 5 to 7 days after sowing, the full stage of seedling emergence can be reached 7 to 10 days, the seedlings emerge basically in the whole period of 15 days, and the final seedling emergence rate is more than 90 percent.

The seedlings begin to emerge 15-20 days after the spring sowing, the full stage of emergence is reached after about 1 month, the seedlings still emerge after 2-3 months, the emergence time is long, and the final emergence rate is usually only 40% -50%.

One of two different sowing modes is sowing in the current 6 months and the other is sowing in the next 3 months, namely the sowing time is earlier by 9 months, in addition, the seedling emergence in spring sowing is slow, the seedling emergence period is long, the growth time of the seedlings in the current year is usually only 1-2 months, and the difference is not large when the plant height is slightly stopped in autumn, so that the time of 1 year is almost saved compared with the traditional spring sowing along with picking and sowing, and the method is favorable for accelerating the breeding process.

The emergence rate and the seedling growth condition of the wintersweet of the 'starlight brilliant' variety in different sowing periods are counted, and the results are shown in table 1.

TABLE 1 statistical table of emergence rate and seedling growth at different sowing periods

As can be seen in Table 1, the rate of seedlings broadcast with harvest is much higher than that of seedlings broadcast in spring, which is 2.18 times that of seedlings broadcast in spring. The difference between the average seedling height and the average ground diameter in the second year is very small and is only 2.61 percent and 2.48 percent respectively, and the difference is not obvious.

B. The statistical results of the flowering stability of the spring sowing seedlings and the high branch grafted and dwarfing flower promoting seedlings are shown in table 2.

TABLE 2 Table for observing flowering stability of different processed Chimonanthus nitens

Note: in the table, the corresponding years of the high-branch grafted seedlings and the high-branch grafted and dwarfing flower promoting seedlings are calculated in 2 years before the seedlings are sown. The stable character means that important characteristic indexes such as the size of the flower diameter, the flower color, the flower fragrance, the number and the length width of the quilt pieces, the length-width ratio of the quilt pieces, the number of male and female cores, the purple veins of the quilt pieces, the flowering phase and the like are basically unchanged, and the unstable character means that the indexes are changed to a certain extent or even greatly.

As can be seen from table 2, the characters of the 'starlight brilliant' seedlings of the easy-to-flower variety are basically stable in the fourth year and are completely stable in the fifth year, and the flowering characters of the 'high branch grafting' and 'high branch grafting + dwarfing flower promotion' grafted plants in the 1 st year are stable, are 1 to 2 years earlier than those of the seedlings, and are beneficial to shortening the breeding period. Meanwhile, the inventor also compares multiple varieties, and the 'high branch grafting' can shorten the breeding period by more than 2 years for most of the varieties.

Example 2

Shorten the seed selection period of the wax plum

(1) Nursery selection and preparation: in 2008, 20 months, land blocks which are leeward and sunny, have flat land, convenient irrigation and drainage, deep soil layer and loose and fertile soil are selected. Deep ploughing and harrowing are carried out before sowing, the ploughing depth is more than or equal to 20cm, and stones and weeds are removed. Making ridges with width of 1-1.2m and height of 30cm, and covering with 1% potassium permanganate or 800 times carbendazim film for sterilization for 7 days. And airing for 2 weeks for later use.

(2) Seed harvesting and processing: and 6, 13 days after 6 months, picking the 'tip of the' waxberry fruit tray, wherein the fruit tray just changes from green to light yellow brown and begins to shrink, and immediately stripping off the seeds for sowing.

(3) Sowing: adopting the following-up sowing, directly sowing the seeds stripped in a seedling bed prepared in advance in 13 days after 6 months, wherein the row spacing is 20-30cm, the plant spacing is 8-10cm, covering soil for 4-5cm after sowing, watering, building a shading shed, and covering with a 50% shading net.

(4) And (3) management of the seeding: watering for 1 time to permeate water basically 2-3 days after sowing, starting to sprout 5 days, reaching the full stage of sprouting 7 days, completely sprouting 15 days, and finally reaching the rate of sprouting 92%. Seedlings grow slowly after emergence of seedlings, when most seedlings grow 3-4 pairs of true leaves, the period is up to 7 months and 20 days, and thiophanate and carbendazim are alternately sprayed for 1 time every 20-25 days to prevent diseases and pests; artificial weeding is carried out for 1 time every 20-30 days, and the influence of weeds on the growth of seedlings is prevented; watering in time after weeding to prevent the seedlings from dying due to poor contact between soil and the wintersweet seedlings or damage of partial root systems caused by soil loosening during weeding; the soil is kept moist at any time in the seedling stage, so that the rapid growth of seedlings is facilitated, and meanwhile, the soil is loosened for 1 time every 1-1.5 months for preventing soil hardening; 20-25g/m per month from 7 last ten days²Applying urea or compound fertilizer for 1 time, and applying phosphorus-potassium fertilizer for 1 time in 10 months to ensure the nutrients required by growth; and in 6-9 months of rainy season, the plants are prevented from dying due to water accumulation by paying attention to water drainage and waterlogging prevention. When the growth of the seedlings stops in 11 months, the height of 0.5 year-old sowed seedlings is generally 15-25cm, and a small amount of the sowed seedlings reaches 30 cm. After spring turning, watering for 1 time before germination, timely and regularly supplementing fertilizer after germination, and continuing to carefully manage and protect according to the mode of the last year, wherein the plant height of a 1.5-year-old plant reaches 90-115cm, the ground diameter reaches 1-1.5cm, and the thickness of a stem reaches 0.8-1.2 cm.

(5) High branch grafting (simultaneously setting a following-seeding seedling propagation comparative example): and (3) grafting the branches of the cultured seedlings in 1.5 years to middle-aged and young-aged mature plants. Adopting a cutting grafting method, wherein the grafting time is 2 months and 19 days in 2010, when the buds sprout to the size of wheat grains (0.3-0.5cm) in spring, selecting 1.5-year-old strong-growing, well-developed, disease and insect-free, short internode and full-developed seeding strong seedlings in 'tip-coated' varieties as scion branches, selecting 8-year-old medium-young flowering wintersweet trees with strong growth as stock, and the stem thickness is 3-4 cm. The stock is cut at a position 50-70cm away from the ground, and 2-3cm is longitudinally cut at the smooth side of the stock to reach the xylem, and the section is smooth; 1-2 pairs of buds of the scion are reserved, the scion is 3-5cm long, the lower part of the scion is cut into a flat wedge shape, a xylem is slightly formed, and a cambium is exposed; the cut scion is inserted into the cut of the stock and aligned with the cambium on one side, and after the cut scion and the cambium are tightly connected, the stock and the cut scion are tightly bound and sealed by a plastic tape (see attached figures 3 and 4).

(6) Managing and dwarfing and promoting flowers after grafting (setting a hormone-free treatment comparative example of the grafted seedling at the same time): after the grafting survives and grows new buds in the middle ten days of 3 months, the budding and young corktree of the stock are removed, and the scion is not bumped. When the sprouts grow 5-8cm in late 3 months, slightly loosening the tied binding plastic belts or cutting off part of the binding belts to facilitate the free growth of the callus at the joint; when the new branch grows to be more than 30cm, the wound is basically healed, all binding plastic belts are removed, and the branch or the small bamboo pole and the like are used for supporting and protecting the grafted branch so as to prevent the grafted branch from being blown off by wind. Other operations such as watering, fertilizing, weeding and soil plowing are the same as normal maintenance management (see the attached figures 5 and 6).

Wherein, when the grafted sprout grows to 5-10cm, 0.8L 1000mg.L is applied to the root^-1PP₃₃₃。

(7) Results

Compared with the hormone-free grafted seedling, the growth of the current-year grafted and extracted branch is generally 1.0-1.3m, the current-year natural flowering rate reaches about 30%, the grafted and extracted branch is mainly centrally arranged at the middle lower part of the branch, and the middle upper part of the branch is not flowering (see figure 7).

The plant treated by high branch grafting and dwarfing flower promotion has the advantages that the growth vigor is slowed down, the branches are thick and strong, the leaf color is dark green, internodes are shortened, the wind resistance is enhanced, the vegetative growth is controlled to a certain degree, the reproductive growth is accelerated, the flowering quantity in the current year is obviously increased, the flowering rate is generally improved by about 40%, the flowering rate of the whole plant reaches 65-70%, 50 grafted plants (branches) in the same batch are almost completely consistent with the flowering characters of the 'tip-covered' chimonanthus nitens mother plant through the flowering phase observation, the corresponding seedling can be eliminated in advance as seed selection, the seedling selection period is shortened (see attached figure 8), and the land occupation and the management and protection cost are reduced.

1 variant plant appears in the group of the following sowing, the high branch grafting and the dwarfing flower promoting group, the character characteristics of the group in the current year are recorded in detail at the end of 2010, and the results are completely consistent with those of the group in 2010 by continuous observation and recording in 2011 and 2012. At the end of 2011, the corresponding sowing seedlings start to flower, the flowering rate is about 5%, and no observation value is provided; at the end of 2012, the flowering rate of the seedlings reaches 40-50%, most characters are basically stable, but the length of the quilt sheet in the quilt and the size of the flowers are greatly increased and decreased; at the end of 2013, the flowering rate of the seedlings reaches over 80 percent, all characters are stable, and the flowering observation is consistent with that of the grafted plants in 2010. The variant is obviously superior to the original variety through biological characteristic observation and variety evaluation (certainly, the variant has a certain fortune component, because the inventor carries out similar treatment on different varieties for years before and after, although the variant also appears, most of the variants are poor or almost poor and have little value), and then the variant is named as 'rich tip quilt'. Compared with the original variety, the flower quantity of the 'Fenghua tip quilt' is increased, the flowers are more dense and about 8-10% dense, the diameter of the flowers is increased by 19-22%, the length of the quilt piece is increased by 17-25%, the width of the quilt piece is increased by 20-27%, the length and the width of the inner quilt piece are slightly increased, but the flowers are not obvious, the flower color is brighter, the fragrance is stronger, the flowering phase is 3-5 days earlier, the duration time is prolonged by 8-15 days, and the comprehensive ornamental value is higher. The variant is finally approved by the forest variety committee of Sichuan province at the end of 2019 through district test and consistency test. (see FIG. 1, FIG. 11)

In the whole process of ' full-grown flower tip by ' seedling seed selection, variant plants are discovered in advance for 2-3 years by a ' random seeding, high branch grafting and dwarfing flower promotion ' comprehensive innovation integration technology, the high branch grafting is applied in advance to verify the hereditary stability (the characters of the grafted plants are consistent with the original corresponding seedling plants, and the grafting can be stably inherited), 1-2 years of time is saved for breeding, and the breeding period (the year limit) is effectively shortened by the new variety breeding of the overall ' full-grown flower tip.

Example 3

'Happy flower fragrance' x 'starlight brilliant' hybrid combined wintersweet

(1) Nursery selection and preparation: and 4, selecting a land block which is leeward and sunny, has flat land, convenient drainage and irrigation, has a deep soil layer and loose and fertile soil in a new capital base of a Sichuan academy of agricultural sciences in 2015 for deep ploughing, wherein the ploughing depth is more than or equal to 20cm, and removing stones and weeds. Harrowing, making furrow with width of 1-1.2m and height of 30cm, pouring formalin, and sterilizing by film covering for 7 days. And airing for 2 weeks for later use.

(2) Seed harvesting and processing: 6 months and 17 days, the hybrid composite wintersweet fruit tray which just changes from green to light yellow brown and begins to shrink is harvested, and seeds are stripped and are ready for sowing.

(3) Sowing: directly sowing the seeds on the prepared seedbed in the same day, wherein the row spacing is 20-30cm, the plant spacing is 8-10cm, covering soil of 4-5cm after sowing, watering, putting up a shed, and covering with 50% sunshade net.

(4) And (3) management of the seeding: watering for 1 time to permeate water basically 2-3 days after sowing, starting to sprout 5 days, reaching the full stage of sprouting 8 days, completely sprouting 15 days, and finally reaching the rate of sprouting about 90%. After emergence, seedlings grow slowly and are sprayed with a water-spraying agent 1: 2: preventing the occurrence of damping off by 200-fold Bordeaux mixture; when most seedlings grow 3-4 pairs of true leaves, spraying thiophanate and carbendazim alternately every 20-25 days when the last 7 months later, and preventing other diseases; the aphid can be sprayed and killed by 50% of octathiophosphoryl emulsion or 50% of fenitrothion emulsion 1000 times, 25% of pirimicarb 3000 times and 20% of imidacloprid 1500-2500 times, the leaf mites can be sprayed and killed by 75% of propargite emulsion 2000 times or 40% of dicofol emulsifiable concentrate 1000-1500 times, 20% of mite killing wettable powder 2000 times and 15% of pyridaben emulsifiable concentrate 2000 times; the artificial weeding is carried out for 1 time every 20-30 days generally, the influence of weeds on the growth of seedlings is prevented, and watering is carried out in time after weeding so as to prevent the seedlings from dying due to poor contact between soil and wintersweet seedlings or damage to partial root systems caused by soil loosening during weeding; the soil can be kept moist at any time in the seedling stage, which is favorable for the rapid growth of seedlings and simultaneously for preventionLoosening soil for 1 time every 1-1.5 months after soil hardening; 20-25g/m per month from 7 last ten days²1 time of dressing urea or compound fertilizer, 1 time of dressing phosphorus-potassium fertilizer in 10 months or 2 per mill potassium dihydrogen phosphate sprayed on leaf surfaces to ensure nutrients required by growth; and in 6-9 months of rainy season, the plants are prevented from dying due to water accumulation by paying attention to water drainage and waterlogging prevention. When the growth of the seedlings stops in 11 months, the plant height of 0.5 year-old sowed seedlings is generally 15-20cm, and a small amount of the sowed seedlings reaches 30 cm. After spring turning, watering for 1 time before germination, timely and regularly supplementing fertilizer after germination, and continuing to carefully manage and protect the plants in the last year, wherein the height of the 1.5-year-old plants reaches 85-110cm, the ground diameter reaches 1-1.5cm, and the thickness of stems reaches about 1 cm.

(5) High branch grafting (simultaneously setting a following-seeding seedling propagation comparative example): and (3) highly grafting the 1.5-year-old young seedling branches on middle-aged and young-aged mature plants. Adopting a cutting grafting method, wherein the grafting time is 22 days in 2 months in 2017, when the buds germinate to the wheat grain size (0.3-0.5cm) in spring, selecting a 1.5-year-old strong-growing, well-developed, disease-free, insect-free, short internode and full-developed seeding strong seedling in a hybridization combination as a scion branch, selecting a 8-10-year-old medium-young flowering wintersweet tree with strong and large growth as a stock, and the stem thickness is 3-5 cm. The stock is cut short at a distance of 60-80cm from the ground, and 2-3cm is longitudinally cut at the smooth side of the stock to the xylem, and the section is smooth; 1-2 pairs of buds of the scion are reserved, the scion is 3-5cm long, the lower part of the scion is cut into a flat wedge shape, a xylem is slightly formed, and a cambium is exposed; and inserting the cut scion into the cut of the stock, aligning the cut scion with a cambium on one side, and tightly binding and sealing the stock and the cut of the scion by using a plastic tape after the cut scion and the cambium are closely connected.

(6) Managing and dwarfing and promoting flowers after grafting (setting a hormone-free treatment comparative example of the grafted seedling at the same time): after the grafting survives and grows new buds in the middle ten days of 3 months, the budding and budding corktree of the stock is removed in time, and the scion is not bumped. When the sprouts are about 5cm long in late 3 months, slightly loosening the tied binding plastic tapes or the binding tapes of the partition parts to facilitate the free growth of the calluses at the joints; when the new branch grows to be more than 30cm, the wound is basically healed, all binding plastic belts are removed, and the branch or the small bamboo pole and the like are used for supporting and protecting the grafted branch so as to prevent the grafted branch from being blown off by wind. And other operations such as watering, fertilizing, weeding, soil plowing and the like are performed with normal maintenance management.

When the grafted sprout grows about 10cm in the year, 1500mg.L-1B9 is sprayed on the leaf surface, the front side and the back side of the grafted sprout are uniformly sprayed, and in order to enable the leaves to fully absorb the grafted sprout, the spraying is repeated for 1 time after about 10 minutes after the first spraying is basically dry.

(7) Results

The plant treated by high branch grafting and dwarfing flower promotion has the advantages of slow growth vigor, thick and strong branches, dark green leaf color, shortened internodes, enhanced wind resistance, certain control on vegetative growth, accelerated reproductive growth, obvious increase of flowering quantity in 2017, improvement of flowering rate by 15-20 percent, 25-30 percent of flowering rate of the whole plant, stable flowering property, basically consistent properties such as the diameter of multiple plants, the number and length of middle or inner flower bedding pieces, the length-width ratio of the bedding pieces, the number of male and female cores, flower color, flowering period, fragrance and the like, and is completely suitable for advanced observation of character characteristics of flower parts (see attached figure 10).

Compared with a comparative example of hormone-free treatment of grafted seedlings, the growth of a grafted and extracted branch in 2017 is generally 0.8-1.5m, the branch thickness is about 0.5-1.2cm, the natural flowering rate is 8-10%, the grafted and extracted branch is mainly centralized at the base position of the branch, and most of the rest positions are not flowering. The observation is not valuable because of the small amount of flowers (see FIG. 9).

In the comparative example of the hybrid combination seeding seedling which is propagated along with sowing and seedling growing, less than 10% of plants are in early blossoming in 2018, the flowering rate is only 2-5%, and no observation value exists until more than 90% of the plants flower in 2019, wherein the flowering rate is less than 15% of the plants, the flowering rate is 10-20% of the plants, the flowering rate is 20-30% of the plants, and the flowering rate is 30-40% of the plants.

In the whole process, even in the mode of 'seeding while picking', the high branch grafted plant advances the observation time of the character characteristics of flowers by at least 3 years compared with the seedling plant, which is beneficial to shortening the breeding period.

The embodiments in the present description are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for shortening the breeding period of Chimonanthus praecox is characterized by comprising the following steps:

(1) seed harvesting and processing:

collecting seeds when the wintersweet fruit tray is changed from green to light yellow brown and begins to shrink, and sowing in time within 2 days after the seeds are stripped;

or immediately mutagenizing after stripping the seeds and sowing in time;

(2) sowing and seedling management:

sowing in a dibble seeding or drill seeding mode, covering soil of 4-5cm after sowing, and shading by a shading net after watering thoroughly; seedling emergence is carried out after 5-7 days, and seedling emergence is basically carried out after half a month;

after 3-4 pairs of true leaves grow out, performing pest and disease damage, grass, fertilizer and water management, removing the sunshade net in 10 months, and culturing for 1.5 years to obtain seedlings to be grafted;

(3) high branch grafting:

grafting the seedling to be grafted on an adult robust wintersweet stock growing for 8-10 years by a high branch grafting method by adopting a cutting method when the average temperature is 15-20 ℃ before the bud germinates in the next spring in the middle and last ten days of 10 months;

(4) dwarfing and flower promoting:

applying PP root to the grafted bud until the bud grows to 5-10cm₃₃₃Or spraying on leaf surfaces B₉。

2. The method for shortening the breeding years of Chimonanthus nitens according to claim 1, wherein the seeding row spacing of the step (2) is 20-30 cm; the distance between plants of the non-mutagenized seeds is controlled to be 8-10cm, and the distance between plants of the mutagenized seeds is controlled to be 4-5 cm.

3. The method for shortening the breeding life of Chimonanthus praecox as claimed in claim 1, wherein the fertilizer management of step (2) is 20-25 g/m/month for a long period²Applying urea or compound fertilizer for 1 time, and applying phosphorus-potassium fertilizer for 1 time in 10 months.

4. The method for shortening the breeding life of Chimonanthus praecox as claimed in claim 1, wherein the stem thickness of the seedling to be grafted in step (2) is 0.8-1.2 cm.

5. The method for shortening the breeding life of Chimonanthus nitens according to claim 1, wherein the step (3) is to cut the Chimonanthus nitens stock into short sections at a height of 40-80cm from the ground and longitudinally cut 2-3cm from one side thereof to the xylem;

selecting the branches of the seedlings to be grafted in the step (2) as scions, reserving 1-2 pairs of buds of the scions, enabling the scions to be 3-5cm long, and cutting the lower parts of the scions into flat wedges;

inserting the cut scion into the cut of the wintersweet stock, aligning the cut scion with a cambium on one side, and tightly binding and sealing the stock and the cut scion by using a fixing band after the cut scion and the cambium are tightly connected;

wherein, the stem thickness of the wintersweet rootstock is 3-5 cm.

6. The method for shortening the breeding life of Chimonanthus praecox as claimed in claim 1, further comprising the step of placing a thermal bag on the grafted part in step (3) during grafting in autumn and winter, and removing the thermal bag after the grafted seedling grows new buds.

7. According toThe method for shortening breeding life of Chimonanthus nitens according to claim 1, wherein the PP in the step (4) is used₃₃₃The concentration is 1000mg.L^-1The application amount of each plant is 0.5-1.0L; b is₉The concentration is 1500mg.L^-1The spraying amount is determined by the spraying humidity of both the front and back surfaces of the leaves.

8. The method for shortening the breeding years of Chimonanthus nitens according to claim 1, wherein the step (4) further comprises:

removing all sprouts and sprouts of the rootstocks after grafted seedlings grow new sprouts in the step (3);

when the grafted sprout grows to 5-8cm, loosening the tied plastic binding belt or cutting off part of the plastic binding belt;

and removing all binding plastic belts when the grafted sprout grows to be more than 30cm, and well performing support protection work of the grafted sprout, or limiting the growth of the grafted sprout by pinching to avoid being blown off by wind.

9. The method for shortening the breeding period of Chimonanthus nitens according to claim 1, further comprising a land preparation step of deep ploughing and raking before sowing, wherein the ploughing depth is more than or equal to 20 cm; making a furrow with width of 1-1.2m and height of 30cm, and sterilizing with 1% potassium permanganate or 800 times carbendazim.

10. Use of the method for shortening the breeding life of Chimonanthus praecox according to any one of claims 1 to 9 in seed selection, cross breeding and mutation breeding.