CN103181286B - Method for overcoming topophysis in vegetative propagation of gingkoes - Google Patents

Abstract

The invention discloses a method for overcoming the position effect of ginkgo asexual reproduction. The present invention solves the problem of position effect in the process of ginkgo asexual reproduction by using the branches with strong growth, full buds, and no pests and diseases in the middle and upper part of the sun crown of the tree as cuttings, and applies the cutting and stubble method to solve the problem of position effect in the process of ginkgo asexual reproduction. Grafting propagation, the trunk can grow vertically upwards. The method not only has low cost, but also has fast seedling growth and high survival rate, and can solve the problem of rapid breeding of fine ginkgo provenances, families, clones and fine individual plants.

Description

The method of overcoming the position effect of ginkgo asexual reproduction

technical field

The invention belongs to the field of asexual reproduction in the cultivation of woody plant seedlings, in particular to a technical process for overcoming the position effect of ginkgo asexual reproduction.

Background technique

Ginkgo biloba is left over from the Quaternary glacier movement, the oldest living fossil and relic plant known to the world among the existing seed plants. It is a special product of our country and is a national second-class protected tree species. The whole body of Ginkgo is a "treasure", which integrates edible, medicinal, economic, ecological, and cultural values. It is the most typical special multi-purpose tree species. China is not only the origin of ginkgo cultivation, the ancient center of introduction and domestication, but also the country with the richest ginkgo resources and species diversity and the largest production and export volume in the world. It has been cultivated in more than 50 countries in the world. Ginkgo has been cultivated in China for 1,000 years, and as an economic forest for 600 years.

Ginkgo propagation includes seed propagation, grafting propagation, cuttings propagation, tissue culture and tree tumor propagation 5 categories. At present, grafting and cutting propagation are the two main ways of ginkgo asexual reproduction. Grafting propagation is one of the main measures of ginkgo seed production in China, Japan, Korea and so on. Ginkgo grafting has a history of at least 400 years in my country. In the 1960s, the United States had carried out the breeding and preservation of fine varieties of male plants through this technology. As early as 1947, Vermeulen, New Jersey, U.S., had begun to conduct research on the propagation of ginkgo male plant cuttings, but it was not until 1951 that Teuseher reported success for the first time. In the 1950s, the Ginkgo cuttings propagation technology attracted the attention of many people in China, and in the early 1990s, this technology was popularized and applied in production. Therefore, grafting and cutting propagation are of great significance for the rapid breeding and early fruiting of improved ginkgo varieties.

However, a prominent theoretical and practical problem of Ginkgo grafted seedlings and cuttings is that they have oblique growth habits, that is, a kind of meristem whose body state is determined by its position on the tree and remains stable during vegetative propagation. Biological phenomenon, called position effect (Topophysis). Although the position effect has the advantages of promoting flower bud differentiation, advancing the fruiting period, and the oblique and arc-shaped growth of branches have laid a good foundation for the production of ginkgo bonsai, it has great disadvantages: (1) It reduces the reproduction of the improved mother tree (2) From the perspective of timber and greening, the position effect often makes the trunk of the propagated good species bend and have poor layering, and cannot reproduce the excellent growth traits of the mother tree; (3) From the perspective of fruit tree cultivation, oblique growth is not convenient for high yield Tree-shaped cultivation, and not conducive to close planting. In this context, a method to overcome the position effect of ginkgo asexual reproduction is proposed. This method utilizes the base of the cutting seedlings to have a large number of hidden buds, which are prone to re-drying and grow vertically upwards. They have the characteristics of rejuvenation and rejuvenation, namely By grafting or cutting with double-dried branches, the main trunk can grow vertically upwards, which can eliminate the position effect.

Contents of the invention

The object of the present invention is to propose a complete set of new ginkgo asexual propagation technology to realize the reproduction of the excellent growth of the mother tree in order to control or eliminate the position effect of the cuttings in order to control or eliminate the position effect of the cuttings during the vegetative propagation of ginkgo. The purpose of improving the traits, improving the reproductive rate of the improved mother tree, and cultivating the high-yield tree shape.

In order to achieve the above object, the present invention adopts the following technical solutions:

(1) Selection of plucked mother trees: The plucked mother trees used for cutting propagation must be excellent varieties of large fruit trees, with large fruit, high quality, high yield, or wood varieties with beautiful tree shape, round and straight stem shape, and fast growth excellent tree;

(2) Selection and treatment of cuttings: Select cuttings with strong growth, full buds, and no pests and diseases. Pick the cuttings in the middle and upper part of the crown of the tree. , keep 2-4 leaves for twig cuttings, the cuttings are 8-10cm long, and the base diameter is 0.3-0.8cm; the hard branch cuttings are 10-30cm long, 0.4-0.8cm thick, and 1.5-2.0cm long after cutting;

(3) The cutting time of tender branches can be carried out in mid-May and transplanting in late June; the cutting time of hard branches can be around March 15 or cutting in autumn, transplanting in spring, the cutting depth is 10-15cm; Spray water once;

(4) Post-cutting management: For tender branch cuttings, it is required to control the temperature of the bed surface at about 30°C, keep the soil moist, and the relative humidity of the air to be about 85%. The relative air humidity is above 80%, the daytime temperature is 21°C-25°C, and the nighttime temperature is 15°C, the optimum soil temperature is 15-20°C, and the light transmittance of the facility awning is 30%-50%. Pay attention to pests and diseases prevention;

(5) Ginkgo is a pre-growth type, and the twig cuttings have no high growth in the same year, so the cutting time should be early to prevent freezing damage in winter. The seedling height of the year is 15.2cm, and the ground diameter is 0.4cm; the hard branches of ginkgo can be placed in the seedbed New branches are drawn, and the germination rate of new shoots can reach about 80%. After the seedlings are transplanted, due to the long seedling period, the amount of rooting in the year is very small;

(6) Flat stubble rejuvenation. The flat stubble tool is pruning shears. The flat stubble time can be carried out 1 year after the cutting seedlings are transplanted, and when the base is re-dried. Note that the stubble should be smooth during the flat stubble, without splitting cracks, leaving The stubble height is 3-5cm; usually, 1 cutting seedling can germinate 3-5 vertically upward-growing multiple stems after flat stubble, and the number of multiple stems increases significantly with age. The scion or cutting propagation obtained from the ear picking nursery can eliminate the position effect.

The beneficial effects of the present invention are:

(1) The position effect suppresses the vegetative growth of the tree, and often makes the trunk of the propagated good species bend, have poor layering, and "short trunk and low crown"; this technology reproduces the excellent growth traits of the mother tree.

(2) The position effect makes the trunk grow obliquely, which is not conducive to the cultivation and dense planting of high-yield tree shape. This phenomenon can be overcome and regulated through this technology.

(3) Effectively increased the reproduction rate of the improved mother tree.

Utilize above-mentioned method to carry out vegetative reproduction by using basal growth and re-drying, to reverse the position effect of fine species, achieve the purpose of rejuvenation and delay clonal aging, the facilities are simple and low, and the method for enriching ginkgo seedlings, especially for the excellent provenance and family of ginkgo , Clonal reproduction and the establishment of fine ginkgo leaf-picking gardens are of great significance.

Description of drawings

Figure 1 Cuttings processing;

Figure 2 Rooting of cuttings;

Figure 3 The effect of cutting position;

Figure 4 Stubble rejuvenation

Note: 3-1 is cuttings with terminal buds, 3-2 is cuttings with stems; 4-1 is flat stubble, and 4-2 is re-drying.

Detailed ways

Example 1:

This research was carried out in Tancheng Ginkgo Breeding Nursery from 1993 to 1995, which belongs to the plastic small arch shed seedbed in the cuttage of the protected area. Choose the branches with strong growth, full buds, and no pests and diseases in the middle and upper part of the crown of the tree as cuttings. Cutting seedlings were cultivated with ABT rooting powder and automatic intermittent spraying. Seedling management is the same as conventional seedling raising. The seedlings are repeatedly stubbled to the lowest position, and stimulated to produce a large number of vertical regenerated shoots, that is, they are re-dried; in the spring of the second year after transplantation, the mother stems are stubbled to promote the germination of fixed or adventitious buds, and the stubble is continued for 2 years After that, the position effect has reversed by the third year. The implementation steps of the Ginkgo cuttings flat stubble rejuvenation method are as follows:

1. Cutting preparation

The tools for cutting are: pruning shears, single-sided blades, budding knives, plastic bags for moisturizing, and buckets. When cutting, put the scion in a moisturizing plastic bag and take it out as you insert it.

2. Selection and processing of cuttings

The twig cuttings are selected to grow robustly, with full buds, and no pests and diseases. The cuttings are picked in the middle and upper part of the crown of the tree. The lower incision site was truncated 1 cm below the bud. The lower cuts are cut into single horse ear shapes with a sharp blade or budding knife. The incision should be on the side of the buds, and the side buds should be kept as much as possible. The part cut off is 1/3 of the diameter of the cuttings, as long as the cambium and xylem are exposed, and the reserved part should be as thick as possible to facilitate rooting. Keep 2-4 leaves. Cuttings are 8-10cm long and 0.3-0.8cm in base diameter, hard branch cuttings are 10-30cm long and 0.4-0.8cm thick.

3. Cutting time

Cuttings in ginkgo protected areas can be divided into four periods according to the degree of lignification of cuttings, and young branches are cut from late May to early August. Hard branch cutting time is around March 15 or cutting in autumn and transplanting in spring. Judging from the rooting effect, the rooting rate can reach more than 95% at other times except in July, which is slightly lower.

4. Cutting method

In order to prevent the skin of the lower incision from being torn, the method of cutting directly through the taper hole or cutting against the wall can be used. After inserting, compact the substrate with your hands to prevent the cuttings from hanging in the air, ensure that the cuttings and the substrate are closely connected, and spray water once immediately. In the future, keep a good growth environment in the cutting bed, ventilated and light-transmitting, and the leaves of different cuttings overlap and squeeze each other carefully when cutting young shoots. The lateral buds at the top of the cuttings face south, and the leaves are all in one line. Under the condition of good spraying facilities, insert as shallowly as possible to ensure good ventilation of the lower incision, and at the same time facilitate seedlings. The insertion depth of young branches is 5-8cm, and the depth of hard branch cuttings is 10-15cm. The best cutting density is 5×10cm.

5. Management after insertion

For tender branch cuttings, it is required to control the temperature of the bed surface at about 30°C, keep the soil moist, and the relative air humidity is about 85%. Hard branch cuttings should be shaded and cooled from May to August to prevent the substrate from drying out, and keep the relative air humidity above 80%. The temperature during the day is 21°C-25°C, and the temperature at night is 15°C. The optimum soil temperature is 15-20°C. The light transmittance of the awning of the facility is preferably 30%-50%. Pay attention to the control of diseases and insect pests.

6. Seedling hardening and transplanting

When the rooting rate reaches 90%, the average rooting number is more than 4. After 45 days of cutting, the seedlings can be hardened and transplanted. Seedling hardening technology is another key measure for the practical application of cuttings in protected areas. The principle of hardening seedlings: Gradually enhance the photosynthesis of rooted seedlings, play the role of protecting tissues, and enhance the adaptability to the external environment. The hardening time is 7-15 days. The control of environmental factors during seedling hardening is opposite to that during rooting, mainly including:

(1) Under the premise of preventing the substrate from drying out, gradually reduce the frequency and amount of water spraying, and carry out drought resistance training for seedlings;

(2) Increase the light intensity. Gradually uncover the reed curtain above to increase the light transmittance in the shed until it is completely removed;

(3) Increase the frequency and intensity of ventilation and reduce the humidity in the shed.

When raising seedlings, carefully dig plant by plant with a shovel to prevent damage to the root system, and try to keep the matrix around the rhizosphere, preferably with soil for transplanting. The root system of ginkgo cuttings is thick and brittle, and it is easy to damage the roots when planting. Therefore, the "ditching and planting method against the wall" should be adopted, that is, a shallow ditch with a depth of 5-10cm and a width of 10cm should be opened on the prepared bed first. , the inner wall of the ditch is vertical. Level the bottom of the shallow ditch, and then plant it with a row spacing of 10×30cm. The best time to plant is before the rain, or even in cloudy days and in the evening. Immediately after planting, irrigate once, and it is best to topdress the roots once a day to reduce the slow seedling period. Generally, it can survive 15 days after planting, and the subsequent management is the same as conventional seedling cultivation.

7. Stubble rejuvenation

It is one of the main features of this invention to carry out stubble and rejuvenation to ginkgo cuttings. The stubble tool is pruning shears, and the specific requirements are:

(1) Selection of the best stubble time: The stubble time can be carried out 1 year after the cutting seedlings are transplanted and when the base has new growth and re-drying. Generally, stubble is carried out after the sap stops flowing in autumn or before the sap starts to flow in spring, preferably from November 20 to March next year.

(2) Height of stubble: The stubble should not be too high. Too high stubble not only causes waste of resources but also is not conducive to sprouting. Generally, 3-5cm of stubble is the most suitable. During flat stubble, the stubble should be smooth without cracks.

(3) Stubble leveling strength: When leveling stubble, each cutting should be fully leveled.

Usually, 1 cutting seedling can germinate 3-5 vertically upward-growing multiple stems after being stubbled, and the number of multiple stems increases significantly with age. This method can be used to establish a scion of excellent varieties, and use the scion obtained from the scion Or cuttings propagation can eliminate the position effect.

The present invention is not limited to the above embodiments, as long as the key technologies such as stubble and rejuvenation are used in the ginkgo cuttings, no matter whether it is combined with measures such as shading, it will fall within the protection scope of the present invention.

Claims (2)

1. overcome a method for ginkgo vegetative propagation position effect, the method comprises the step of following order:

(1) adopting bar elite stand selects: for the improved seeds that bar elite stand must be the large tree of result of adopting of cottage propagation, fruit is large, high-quality, high yield, or tree-like grace, form satisfactorily material perfectly straight, fast growth use kind select tree;

(2) cuttings is selected and is processed, select robust growth, bud full, without damage by disease and insect cutting, adopt bar in tree crown sunny side middle and upper part, cuttings upper cut is flat nick, lower cut is cut into single horse ear shape with sharp blade or budding knife, spray cutting retains 2-4 sheet leaf, the long 8-10cm of cuttings, base footpath 0.3-0.8cm; The long 10-30cm of hardwood cuttings cuttings, thick 0.4-0.8cm, the long 1.5-2.0cm of bevel;

(3) the epicormic branch cuttage time carried out in mid-May, and late June transplants; About March 15 cuttage time or Autumn Cutting, spring transplant, cuttage degree of depth 10-15cm; Taper hole straight cutting, after inserting, spray is once permeable;

(4) after cuttage, manage epicormic branch cuttage requirement control bed surface temperature 30 DEG C of left and right, keep ground moistening, relative air humidity 85% left and right, the cooling of will sheltering from heat or light in cuttage 5-8 month, prevents that matrix from becoming dry, keep relative air humidity more than 80%, daytime temperature is with 21 DEG C-25 DEG C, and be advisable night with 15 DEG C, and the suitableeest soil temperature is 15-20 DEG C, facility cool canopy light transmittance is advisable with 30%-50%, notes the extermination of disease and insect pest;

(5) ginkgo seedling belongs to early growth type, and epicormic branch cuttage is then without high growth, and therefore cutting time is to be early advisable, in case there is freeze injury winter, height of seedling 15.2cm then, leading thread 0.4cm; The hard branch of ginkgo gets final product pumping shoot in seedbed, and young sprout germination rate reaches 80%, and after nursery stock transplanting, because seedling-slowing stage is long, the amount of taking root is little then;

(6) stump rejuvenation, stump instrument is shrub and hedge trimmer, and the stump time transplants when latter 1 year, base portion have new life dry again and carries out in cuttage seeding, and while noting stump, crops for rotation want level and smooth, without splitting a batch breach, stubble height 3-5cm; Common 1 strain cuttage seeding is germinated the multiple dry of 3-5 growth vertically upward after stump, and doing again number with age growth obviously increases, and sets up improved seeds cutting orchard by this approach, scion or the cuttings breeding elimination position effect of utilizing this cutting orchard to obtain.

2. a kind of method that overcomes ginkgo vegetative propagation position effect according to claim 1, is characterized in that, the Best Times of described step (5) acclimatization and transplants is epicormic branch cuttage after 45 days, and cuttage is after 35 days.

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