CN109121771B

CN109121771B - Rapid cuttage breeding method for ulmus davidiana hard branches

Info

Publication number: CN109121771B
Application number: CN201811043165.1A
Authority: CN
Inventors: 鲁仪增; 刘立江; 李文清; 解孝满; 韩义; 孙涛; 王艳; 王宁
Original assignee: CENTER FOR FOREST GENETIC RESOURCES OF SHANDONG PROVINCE
Current assignee: CENTER FOR FOREST GENETIC RESOURCES OF SHANDONG PROVINCE
Priority date: 2018-09-07
Filing date: 2018-09-07
Publication date: 2020-08-04
Anticipated expiration: 2038-09-07
Also published as: CN109121771A

Abstract

A method for rapid cutting propagation of ulmus davidiana hard branches relates to the technical field of vegetative propagation seedling raising, and comprises the following steps of (1) before germination of ulmus davidiana, selecting a stock plant with excellent growth vigor to collect annual robust branches, shearing off branches, (2) cutting the branches into cuttings with 3-5 buds and 8-10 cm in length, and soaking in 1000 times of 50% carbendazim wettable powder for 30min, (3) mixing turf, vermiculite and perlite to serve as a cutting matrix, filling the cutting matrix into a hole tray, disinfecting the hole tray with potassium permanganate solution, taking IBA800 mg/L solution as a rooting agent, soaking the base of the cuttings for 3cm for 30min, (4) punching the hole tray, cutting and fixing the cuttings, and watering the 75% chlorothalonil wettable powder 1000 times of the watering matrix, spraying water for 2-4 times every day after cutting, alternatively spraying two bactericides every 3d, controlling the temperature and humidity, transplanting after 60d of cutting, and (6) before transplanting, not watering for 3d, fixing the cuttings, watering the cuttings after the water, performing general management after 1 week, and achieving a good root growth effect and a friendly rooting environment.

Description

Rapid cuttage breeding method for ulmus davidiana hard branches

Technical Field

The invention relates to the technical field of asexual propagation and seedling culture in forestry science, relates to a woody plant hardwood cutting breeding method, and particularly relates to a rapid cuttage breeding method for ulmus davidiana hardwood.

Background

Ulmus davidiana (Hance) Planch, also known as pivot and branch elm, is a rare and precious tree species of Ulmus davidiana (Ulmaceae) and has a height of up to 10m, and is mainly distributed in China and Korea. The single genus and single species of the plant are obviously different from the genus Ulmus (Ulmus) and the genus Zelkova (Zelkova) in the aspects of fruit wing, cotyledon symmetry, pollen shape, chromosome number, seed oil fatty acid and the like, thorns and the like, and are important transition groups in the Ulmaceae system evolution research.

The spiny elm is a tree species with the advantages of light preference and deep root, hard small branches, spines, drought resistance, cold resistance, barren resistance, wind and sand resistance, very strong adaptability, strong tillering capability and long service life, is a pioneer local soil tree species and an ideal tree species of a biological fence which are difficult to recover and rebuild vegetation in the northern area of China, has good comprehensive improvement effect on soil fertility, can meet the afforestation with different functions in a spiny type and a spiny type, and has positive promotion effect on the aspect of maintaining the functions of the regional ecological system and protecting the biological diversity; meanwhile, the method is also an important tree species for materials and potted landscape; the total flavone and the water extract of the ulmus davidiana var have medical and edible values, have prevention and treatment effects on hyperlipidemia and certain inhibition effect on tumors, and the thorn of the ulmus davidiana var can be developed to provide a new resource of flavone components and show remarkable antioxidant activity. In order to accelerate the development and utilization of the slippery elm, many scholars develop researches on sexual and asexual propagation technology, planting technology and afforestation technology of the slippery elm.

At present, the sanguisorba spinifera is mainly bred by seeds. For more than 20 years, some scholars have successively developed the collection and utilization of wild elm seeds (Sun Hapeng, 1992), the influence of different temperatures on the germination characteristics of elm seeds, sowing and seedling raising and other researches (Kongfeng, 2008; Caoyu, etc., 2016; Sun Hahong, 2016; Caoyu, 2017), which preliminarily solve the problems of seedling breeding, but 70-80% abortion of elm pollen under natural conditions, low fruit fertility rate (Chinese plant society of sciences, 1998), easy loss of vitality of seeds, complicated procedures of seed collection, treatment, sowing and the like, large workload, low seed breeding efficiency, large variation of seedlings and no contribution to the maintenance of mother tree characters.

In the aspect of asexual propagation of Ulmus davidiana var, a few scholars explore methods such as grafting, tissue culture and cuttage propagation. If the other best grafting method (complementary good, 2016) is adopted, the operation method is ingenious, but tools such as a special conical drill bit and a pencil sharpener are needed, and the stainless steel nail is screwed and inserted, so that the operation is complicated, the cost of labor, tools and the like is high, the propagation efficiency is low, and the rapid factory breeding is not facilitated; in addition, due to the defects of seedling growing, the stock grafted by the Ulmus davidiana Benth stock is lack, and has the phenomena of thorn, grafting incompatibility with Ulmus davidiana and the like, so that the development of the Ulmus davidiana grafting method is limited, and the requirement of the Ulmus davidiana clone nursery stock cannot be met.

Zhangyujie developed a Ulmus davidiana tissue culture seedling subculture method (Zhangjie, 2017), but the rooting problem is not solved, and the Ulmus davidiana tissue culture seedling subculture method cannot be applied to fields from laboratories; and the tissue culture propagation method is limited by experimental conditions and high cost.

The utilization of field nutritive organs to quickly propagate the Ulmus davidiana seedlings is a dream of several generations of forestry people. 35 years ago, the root-growing rate of the root section of the garden burnet root can reach 88% reported by the dream of Wangmeng, but the survival rate of the branch which is soaked in water and is cut in one year is only 24%. The cuttage survival rate tested for many years always lingers 18-30% (Sun Qin et al, 1990), and Sun Qin et al think that the branch of Ulmus davidiana has thorns and is not suitable for vegetative propagation. Hardbranch post-germination-hastening cuttage method reported by Harson Gawa et al (Bauhsen Gawa et al, 2015), which requires collecting branches (annual branches with diameter of more than 0.6 cm) in winter, cutting into 12-15cm, wrapping with wet towels, placing in a 0-minus 5 ℃ freezer or cellar for sand storage for 2 months, immersing in water for 1-2 days in last 5 months, and then cuttage in field, and finally needing careful watering, fertilizing, bud picking, pruning and other works. The method has large workload, long management period and possibly influenced survival rate, and the cuttage survival rate is not mentioned in the document. Yan Shulan and the like (Yan Shulan and the like, 2012) invents a rooting agent for elm twig cutting seedling, which consists of indolebutyric acid, 2, 4-dichlorophenoxyacetic acid, boric acid, potassium permanganate, ethanol and water according to a certain proportion. The rooting agent is used for treating semi-lignified tender branch cutting slips (with the length of 10-15cm and the dipping depth of 2-3cm) collected before 7 am or 17 pm after treatment by quick dipping for 1-2s, the cutting slips are subjected to upper opening flat shearing, lower opening horse ear shape and 6-8 leaves reserved, cutting is carried out on a seedbed of a full-light automatic intermittent spraying device, and the rooting rate is as high as 92.8% -100%. However, the patent does not specify a cutting medium. In addition, the formula of the rooting agent contains limited or toxic substances which are easy to prepare toxin, such as potassium permanganate has strong oxidizing property, toxicity and explosiveness, and is difficult to buy by ordinary people; 2, 4-dichlorphenoxyacetic acid also belongs to toxic substances, and is harmful to the body after being ingested or absorbed by the skin; boric acid is commonly used in industrial production, is easily absorbed by injured skin to cause poisoning, and can cause digestive tract symptoms, dermatitis, alopecia and liver and kidney damage; the substances are not only not friendly to the environment, but also have great harm to human bodies, are difficult to purchase and are difficult to popularize and implement. Plum crystal also mentions Yan Shulan and the like in the literature to invent a rooting agent for the cuttage of Ulmus davidiana, and the rooting agent special for the cuttage and seedling raising of twigs is used, and the rooting rate of cuttings treated by quick dipping is more than 98% under the support of a full-light spraying facility, but no reference literature is found.

The research on asexual propagation technologies such as grafting, tissue culture or cuttage and the like is very weak, the implementation cases are few, and the prior art and the formula can not meet the breeding requirements of simplification, scale production and environmental friendliness; however, the related research trend shows that the cuttage breeding of the slippery elm is the most promising and low-cost breeding technology at present, and a related technology system is urgently needed to be developed and established.

Disclosure of Invention

The invention provides a rapid cuttage breeding method for ulmus davidiana hard branches, which adopts an environment-friendly formula and solves the technical problems that the cuttage technology in the prior art is immature, the scion is insufficient, the cuttage is limited by the time of morning, evening and night, the breeding efficiency is low, the seedling rate is low, the cost is high and the industrialization is not facilitated.

The invention is realized by the following steps:

(1) seed strip selection and pretreatment

Before the slippery elm sprouts, selecting a stock plant with excellent growth vigor to collect annual robust branches, and cutting off branch spines, branch bases with the thickness of more than 1cm and branch tips with the thickness of less than 0.35 cm;

(2) cutting and processing of cutting slips

Cutting the branches pretreated in the step (1) into cutting slips with 3-5 buds and 8-10 cm length, bundling a plurality of cutting slips according to the specification of a plug tray, and soaking in 1000 times of 50% carbendazim wettable powder for 30min for sterilization;

(3) preparation of cuttage substrate and rooting agent

Mixing turf, vermiculite and perlite which are 30:10:1 to serve as a cutting medium, filling the cutting medium into a plug tray, disinfecting the plug tray with 800 mg/L potassium permanganate solution, preparing a rooting agent which is IBA800 mg/L solution, treating the base part of the cutting shoot obtained in the step (2) for 3cm, and soaking for 30 min;

(4) cutting

Punching a hole in the middle of each cutting position in the plug tray, putting the cutting slips processed in the step (3) into the holes, fixing, and completely pouring the substrate with 1000 times of solution of 75% chlorothalonil wettable powder;

(5) post-cuttage management

Spraying water for 2-4 times every day after cuttage, and alternately spraying 1000 times of liquid of 50% carbendazim wettable powder for sterilization and 1000 times of liquid of 75% chlorothalonil wettable powder for sterilization every 3 days; opening a sun-shading net for shading, and increasing illumination after new leaves are shown;

keeping the humidity in a greenhouse to be above 70% during cuttage, keeping the temperature at night to be not lower than 10 ℃ and keeping the temperature at day to be not higher than 28 ℃;

after 3 weeks of cuttage, 1 time of foliar fertilizer can be sprayed every week;

after 4 weeks of cuttage, the cutting shoots start to root, basically all roots are rooted after 6 weeks of cuttage, and the cuttings can be transplanted after 60 days of cuttage;

(6) hardening off and transplanting

After 7 weeks of cuttage, reducing watering times to once every 3 days, watering nitrogen phosphorus potassium compound fertilizer for 1 time every week, except that a sunshade net is opened for shading in sunny high-temperature weather 10: 00-15: 00 every day, receiving full light in other time, controlling the temperature below 28 ℃ and the humidity above 50% for hardening seedlings;

and after 60d of cuttage, carrying out portable cuttage on the seedling base, fully combining the substrate with the root system, transplanting, not watering 3d before transplanting, after transplanting and fixing the cutting, thoroughly watering with big water, properly shading in sunny high-temperature weather, and performing conventional management after transplanting for 1 week.

As a preferred embodiment, the upper opening of the cutting shoot in the step (2) is truncated and is about 1cm away from the upper bud, and the lower opening of the cutting shoot is cut into a horseshoe-shaped oblique opening and is about 0.5cm away from the lower bud.

As a preferred embodiment, the hole punched by the plug in the step (3) has a depth of 3cm and a diameter of 1 cm.

As a preferred embodiment, the foliar fertilizer used in step (5) is 0.1% monopotassium phosphate or urea.

The method has the beneficial effects that ① scion resources are rich, annual branches can be used as cutting slips before germination in spring, ② cutting is not limited by time, cutting can be performed within one day without being limited by early, middle and late time, ③ adopts an environment-friendly formula, ④ environmental conditions are convenient to control, the operation is simple, the rooting is rapid, the propagation efficiency is high, the seedling rate is high, the industrial production is facilitated, ⑤ cutting time is early, the growth period of cutting seedlings is long, the growth quantity is large, and the qualified rate of nursery stocks is high.

Drawings

FIG. 1 is a schematic view illustrating the bundling and sterilization of the hard branch cuttings of Ulmus davidiana var;

FIG. 2 is a schematic view of the treatment and cutting of the slippery elm cutting shoot of FIG. 1;

FIG. 3 is a schematic diagram of rooting of the cutting shoot of FIG. 1 at 4 weeks of Ulmus davidiana cutting

FIG. 4 is a schematic diagram of the vigorous growth of the Ulmus davidiana cutting seedling of FIG. 3;

FIG. 5 is a schematic view of the FIG. 4 state of the Ulmus davidiana cutting seedlings after hardening off and before transplanting;

FIGS. 6 and 7 are schematic views of the root system of the Ulmus davidiana cutting seedling of FIG. 4;

FIG. 8 is a schematic diagram of an exemplary transplanting process of Ulmus davidiana cutting seedlings;

FIG. 9 is a schematic diagram of an embodiment of transplanting survival.

Detailed Description

Examples

A fast cuttage breeding method for ulmus davidiana hard branches comprises the following steps:

the fast cuttage propagation method of Ulmus davidiana hard branch includes the following steps:

1 strip selection and pretreatment

In 3 last ten days of Shandong Jinan, before the Ulmus davidiana germinates, selecting a stock plant with excellent growth vigor to collect annual robust branches, and cutting off branch spines, branch bases with the thickness of more than 1cm and branch tips with the thickness of less than 0.35cm to obtain branches with the diameter of 0.35-1 cm.

2 cutting and processing of cutting shoots

Referring to the attached figure 1, the pretreated branches are cut into cutting slips with 3-5 buds and the length of about 8-10 cm, the upper openings of the cutting slips are truncated and are about 1cm away from the upper buds, and the lower cutting openings are cut into horseshoe-shaped oblique openings and are about 0.5cm away from the lower buds. Bundling is carried out when every 32 cuttings are cut, the bundling quantity is according to the specification of a plug tray, the plug tray with 32 holes is adopted in the embodiment, and the plug tray is placed in 1000 times of 50% carbendazim wettable powder to be soaked for 30min for sterilization treatment.

3 preparing cuttage substrate and rooting agent

The method comprises the steps of selecting turf, vermiculite and perlite which are 30:10:1 as a cutting matrix, filling the cutting matrix into a plug tray, disinfecting the plug tray by using a potassium permanganate solution of 800 mg/L, preparing a rooting agent, wherein the rooting agent is an IBA800 mg/L solution, and treating the base of a cutting shoot for 3cm and 30 min.

4 cutting

Drilling a hole with the depth of 3cm and the diameter of 1cm in the middle of each cuttage position in the hole tray, referring to the attached figure 2, placing the well-treated cutting slips into the holes on the hole tray, fixing the cutting slips, and pouring 1000 times of liquid of 75% chlorothalonil wettable powder to a substrate thoroughly.

5 post-cuttage management

Spraying water for 2-4 times every day after cuttage, and alternately spraying 1000 times of 50% carbendazim wettable powder and 1000 times of 75% chlorothalonil wettable powder every 3 days for sterilization; and opening the sunshade net to shade, and properly increasing the illumination after the new leaves are shown.

And (3) keeping the humidity in the greenhouse to be more than 70% during the cuttage, keeping the temperature at night to be not lower than 10 ℃, and keeping the temperature at day to be not higher than 28 ℃.

After 3 weeks of cuttage, foliage fertilizers such as 0.1% monopotassium phosphate/urea and the like can be sprayed every week for 1 time.

Referring to the attached figure 3, figure 4, figure 6 and figure 7, after 4 weeks of cutting, the cutting shoots begin to root, when 6 weeks of cutting, the cutting shoots all root basically, and after 60 days of cutting, the cutting shoots can be transplanted, referring to the attached figure 5.

6 hardening and transplanting seedlings

After 7 weeks of cuttage, the watering frequency is reduced to once every 3 days, nitrogen, phosphorus and potassium compound fertilizer is applied for 1 time every week, except that a sunshade net is opened for shading in a sunny high-temperature day of 10: 00-15: 00, the other time is subjected to full light, the temperature is controlled below 28 ℃, and the humidity is controlled to be more than 50% for seedling hardening.

Referring to the attached drawing 8, after 60d of cuttage, the seedling base is lifted by hand, the substrate and the root system are fully combined, transplanting can be carried out, 3d before transplanting is not watered, the cutting shoot and the substrate are lifted out from the plug tray and transplanted to a double-color flowerpot, and the specification of the double-color flowerpot is as follows: the upper caliber and the lower caliber are 21 and 14.5 and 17cm, the seedling substrate is filled into a fixed planting hole or is moved into a fixed planting hole in a strong seedling cultivation garden, surface soil is filled, after the cutting is fixed, the cutting is watered thoroughly, and the shade is properly covered in sunny high-temperature weather. And (5) performing conventional management such as watering, fertilizing and the like after transplanting for 1 week.

Referring to the attached figure 9, in the hardening-off period, the cutting seedlings take roots and grow vigorously, and the average cutting survival rate can reach more than 98.96%.

Screening experiment for ulmus davidiana hard branch cuttage optimum conditions

1 materials and methods

1.1 test sites and materials

The test is carried out in an intelligent greenhouse of a Hongkou conservation bank (Shandong Jinan) of forest germplasm resources center in Shandong province, and materials are collected from a Langhua David resource conservation garden of the Hongkou conservation bank. The test material selects 2-3 years old mother plants with excellent growth vigor before germination (3 last ten days of Shandong Jinan), collects annual robust branches, and cuts off branch spines, branch bases with thickness larger than 1cm and branch tips with thickness smaller than 0.35 cm.

1.2 test methods

And (3) carrying out orthogonal experimental design by adopting SPSS19.0 software, and carrying out cuttage treatment according to an orthogonal design scheme.

1.2.1 protocol

Selection of the testFour factors including common hormone type, hormone concentration, treatment time and matrix, wherein each factor is selected from 5 levels, L₂₅(5⁶) Orthogonal design tables. The factors and levels are shown in Table 1, and the orthogonal protocol is shown in Table 2.

TABLE 1 test factors and levels

Remarking: the treatment time level "0" represents a quick dip of 2 s.

Table 2 orthogonal design test protocol

1.2.2 cuttage test

1.2.2.1 preparation of matrix and hormone

1.2.2.1.1 matrix preparation

According to the test protocol, 5 matrices were prepared in proportions and placed in 32-well plates with dimensions of top diameter, depth of well and bottom diameter of 6, 5, 3cm and sterilized with 800 mg/L potassium permanganate solution.

1.2.2.1.2 hormone formulation

According to the test scheme, 5 hormones and the concentrations thereof are respectively prepared and packaged for later use.

1.2.2.2 cutting and pretreatment

And cutting the collected branches into cutting slips with 3-5 buds and the length of about 8-10 cm, wherein the upper openings of the cutting slips are truncated and are about 1cm away from the upper buds, and the lower cutting openings are cut into horseshoe-shaped oblique openings and are about 0.5cm away from the lower buds. Bundling every 32 cuttings, and soaking in 1000 times of 50% carbendazim wettable powder for 30min for sterilization.

1.2.2.3 cuttage test

And (3) respectively treating the disinfected cutting slips according to a scheme, repeating each test treatment for 3 times, and carrying out cuttage on the treated cutting slips. When cutting, a hole with the depth of 3cm and the diameter of 1cm is drilled in the middle of each cutting position in the hole tray, the well processed cutting is placed in the hole, the cutting is fixed, and 1000 times of liquid of 75% chlorothalonil wettable powder is used for pouring the substrate thoroughly.

1.2.2.4 post-cuttage management

Spraying water for 2-4 times every day after cuttage, and alternately spraying 1000 times of liquid of 50% carbendazim wettable powder for sterilization and 1000 times of liquid of 75% chlorothalonil wettable powder for sterilization every 3 days; and opening the sunshade net to shade, and properly increasing the illumination after the new leaves are shown.

And (3) keeping the humidity in the greenhouse to be more than 70% during the cuttage, keeping the temperature at night to be not lower than 10 ℃, and keeping the temperature at day to be not higher than 28 ℃. After 3 weeks of cuttage, 0.1% monopotassium phosphate/urea foliar fertilizer can be alternately sprayed for 1 time every week. And (4) investigating rooting conditions every 3d after cuttage, and carrying out survival rate investigation after 60 d.

1.2.3 data processing

1.2.3.1 data investigation methods:

(1) callus time: the day from cutting to observing that 1 cutting shoot generates callus is the callus treatment time, the day of cutting is 1d, and the investigation is carried out every 3 d.

(2) Rooting time: the days from cutting to observation that 1 cutting shoot takes root is the rooting time of the treatment, the day of cutting is 1d, and the investigation is carried out every 3 d.

(3) Survival rate: the ratio of the number of rooting cuttings to the total number of cuttings.

(4) Callus rooting rate: the ratio of the number of cuttings with callus rooting to the total number of surviving cuttings is only.

(5) Mixed rooting rate: the ratio of the number of cuttings with two rooting types of callus rooting and skin rooting to the total number of surviving cuttings is provided.

(6) Root-growing rate of the bark: the ratio of the number of cuttings with skin rooted to the total number of surviving cuttings is only.

(7) The number of roots is as follows: the number of the cutting opening of the cutting slips and all the main roots of the bark.

(8) Root length: the length of the longest root in the root system of the cutting.

(9) Thickness of base of stiff branch: the thickness of the upper edge of the lower cutting opening of the cutting slips.

(10) The length of the branches is as follows: the length from the base of the longest branch from winter bud to growing point.

(11) The number of blades is as follows: the number of all leaves growing on the branch.

1.2.3.2 Each index weight

According to the survival requirement of cuttage and the quality of cuttage seedlings, indexes and important degrees adopted by the experiment for analyzing and screening the optimal cuttage conditions are survival rate, number of rooting strips, root length, rooting time, branch length, leaf number and callus time in sequence.

1.2.3.2 data measurement and analysis

The data were measured using a ruler and a vernier caliper.

The data processing uses Excel 2013 and SPSS19.0 software.

1.3 cutting results

The result of the hard branch cutting test of the slippery elm is shown in the table 3, the highest survival rate of the No. 18 treatment is 0.9896, and the second survival rate is 0.9688 and 0.8229 of the No. 19 treatment. The longest length of the branch is 18, the length is 22.34cm, and the second length is 19 and 15, the length is 16.94cm and 15.63cm respectively. The most abundant number of roots is 18, the average number of roots is 5.14, and the second is 4.11, 24.92. The longest root length is 25 # 10.72cm, 18 # 10.30cm and 13 # 9.83 cm. The shortest rooting time is 9, 18 and 19, the average rooting time of the three treatments is 27d, and the second treatment is 28d for No. 1 and 20, and the second treatment is 30d for No. 14 and 22. The sanguisorba hardwood cutting rooting mainly comprises callus rooting and bark rooting, and the rooting rate of No. 22 and No. 12 bark treatment reaches 0.6. In addition, referring to the attached figure 1, the survival rate is consistent with the callus rooting rate, the root length, the number of the rooting strips and the rooting time, and deviates from the skin rooting rate; the development length is basically consistent with the trend of the number of leaves, the thickness of the base part of the hard branch is similar to the trend of the callus time, and the rooting rate of the bark part is similar to the trend of the mixed rooting rate.

Experimental example 1 hormone type screening

The influence of four hormone types of ABT1, ABT2, GGR, NAA and IBA on various cuttage indexes is shown in table 4, k1 is ABT1, k2 is ABT2, k3 is GGR, k4 is NAA, k5 is IBA elm hardwood cuttage, IBA is the best hormone, ABT1 times, GGR and ABT2 are poor, and NAA is the worst. The cuttings treated by IBA have the earliest callus, the shortest rooting time, the largest number of main roots, the longest root system and the largest number of leaves, the survival rate and the new branch growth amount are only second to ABT1, and the difference is very small.

The survival rate of the cuttings and the growth amount of new branches processed by ABT1 are all larger than those of other hormones, the number of main roots, the callus appearing time and the rooting time are only inferior to IBA, but the promotion effect on the root growth is small, and the root length is short. GGR is amino acid nutritional agent, can obviously shorten rooting time, promote branch and leaf and root system growth, but it appears callus time latest, survival rate is minimum and main root quantity is minimum. ABT2 has good promotion effects on callus formation, root length and main root number, but has small effects on survival rate, rooting time and branch and leaf growth. Compared with other hormones, NAA has a moderate effect on promoting survival rate, but has weak effects on promoting callus formation, rooting time, main root number, root length and branch and leaf growth.

In addition, the mixed rooting rate and the skin rooting rate of the cuttings treated by IBA, GGR and ABT1 are lower than the callus rooting rate, which indicates that the mixed rooting rate and the skin rooting rate of the cuttings treated by ABT2 and NAA are relatively higher than the callus rooting rate, and the skin rooting rate is higher than that of the other 3 hormones.

TABLE 4 Effect of hormone types on various cuttage indexes

Note: y, H, P, the callus rooting rate, the mixed rooting rate, the bark rooting rate, the same as the following steps

Experimental example 2 hormone concentration screening

The results of the hormone concentration screening are shown in Table 5, wherein k1 in Table 5 refers to 0 mg/L, k2 refers to 200 mg/L, k3 refers to 400 mg/L, k4 refers to 600 mg/L, and k5 refers to 800 mg/L. from Table 5, the concentrations of the sanguisorba officinalis hardwood cutting hormone are preferably 800 mg/L, 600 mg/L times less than 400 mg/L times, 200 mg/L times less good, and 0 mg/L times less good.

The callus appears in the cutting treated by 800 mg/L at the earliest, the survival rate, the branch and leaf growth amount and the main root amount are all superior to other concentrations, the rooting time is only second than 600 mg/L, the root length is only second than 400 mg/L, the difference is small, the cutting treated by 600 mg/L and 400 mg/L have better promoting effect on the callus formation time, the survival rate, the branch and leaf growth amount and the main root amount, in addition, the cutting treated by 600 mg/L has the shortest rooting time and shorter root length, the cutting treated by 400 mg/L has the longest root system but longer rooting time, and compared with other concentrations, 200 mg/L has the promoting effect on various indexes of the hard branch cutting of the slippery elm, but weaker survival rate, main root amount and rooting time are obviously better than the contrast concentration of 0 mg/L.

In addition, the ratio of rooting of the bark parts of the cutting shoots treated by 800 mg/L and 600 mg/L to the mixed rooting is relatively high, the rooting promotion effect on the bark parts is strong, the ratio of rooting of the 400 mg/L treated mixed roots is high, but the ratio of rooting of the pure bark parts is small, the rooting promotion effect on the bark parts is equivalent to that of 200 mg/L on the whole, the rooting rate of the bark parts of the cutting shoots is relatively small, and the rooting rate of the bark parts of the cutting shoots is extremely low, so that the rooting promotion of the bark parts can be reflected by hormone treatment.

TABLE 5 Effect of hormone concentration on various cuttage indexes

Experimental example 3 treatment time screening

The results of the treatment time screening experiments are shown in table 6, wherein k1, k2, k3, k4 and k5 in table 6 refer to quick dipping, 15min, 30min, 45min and 60min respectively. As shown in Table 6, the most suitable hormone treatment time for the hard branch cutting of Ulmus davidiana var is 30min or 45min, and 15min and 60min times, the quick dipping effect is the worst.

The survival rate and rooting time of the cuttings treated by the hormones for 30min and 45min are superior to those of other treatment time, and the difference between the survival rate and the rooting time is small. The new branch growth amount of the cutting processed in 30min is the largest, the leaf number is slightly smaller than the maximum value, but the callus formation time and the main root number are general, and the root length is smaller than other processing time; the number of main roots of the cutting shoot treated in 45min is more than that of other treatment time, the callus forming time is slightly longer than the shortest time, but the promotion effect on the growth of roots, branches and leaves is small. The root system of the cutting processed in 15min is the longest, the number of leaves is the largest, the growth amount of new branches and the number of main roots are slightly less than the optimal processing time, but the survival rate is obviously less than two processing times of 30min and 45min, and the rooting time is the latest. The root length of the cutting processed in 60min is only 15min, the difference is small, the cutting has promotion effects on forming callus, shortening rooting time and number of main roots, but the branch and leaf growth amount is small, and the survival rate is lowest. The callus treated by quick dipping appears earliest, but the growth amount of branches and leaves, the survival rate, the root length and the rooting time are relatively poor, the number of main roots of the cutting shoot treated by the quick dipping method is minimum, and the comprehensive performance of each index is worst.

In addition, the rooting rate of the bark part is highest after 45min treatment, the rooting rate of the mixed root part after 30min treatment is highest, the rooting rate of the mixed root part after 15min treatment and the rooting rate of the bark part are relatively high, and the 3 treatment times are favorable for the rooting of the bark part; the rooting rate of the skin part is low by quick dipping and 60min treatment, and the promotion effect on the rooting of the skin part is relatively weak.

TABLE 6 influence of treatment time on various cuttage indexes

Experimental example 4 cutting substrate screening

The screening results of the cutting medium are shown in table 7, wherein k1, k2, k3, k4 and k5 in table 7 respectively refer to river sand, grass peat, vermiculite and grass peat: 2:1 of perlite, 2:1 of grass carbon: vermiculite: perlite is 3:1: 0.1. As can be seen from table 7, the cutting medium was prepared from turf: vermiculite: the best perlite is mixed with 3:1:0.1 matrix, pure grass carbon is used, grass carbon: perlite is 2:1 mixed matrix, vermiculite is poor, river sand is worst.

Grass carbon: vermiculite: the perlite mixed matrix has better main root quantity, root length and branch and leaf growth quantity than other matrixes, the survival rate is second to the highest value, but the callus formation time and the rooting time are longer. The pure turf matrix has the shortest callus forming time and rooting time, the highest survival rate, better main root quantity and branch and leaf growth quantity, and medium root length. Grass carbon: the perlite-2: 1 mixed matrix has the advantages of short callus forming time, long root system length, medium survival rate and main root quantity, low branch and leaf growth amount and longest rooting time. River sand is used as a cutting medium, the rooting time is earlier, the callus emergence time is medium, but the survival rate, the number of main roots, the root length and the growth amount of branches and leaves are the worst.

In addition, the mixed rooting rate of the cuttings treated by the river sand accounts for the highest ratio to the skin rooting rate, and the skin rooting rate is obviously higher than the callus rooting rate; grass carbon: the mixed rooting rate of perlite and mixed matrix 2:1 and the rooting rate of the bark part are respectively second to river sand, but the difference between the numerical value and the river sand is large; grass carbon: vermiculite: the mixed matrix of perlite in a ratio of 3:1:0.1 has medium rooting rate, and the rooting rate of the bark part is lowest; the rooting rate of the vermiculite bark part is medium, and the mixed rooting rate is lowest; the pure turf mixed rooting rate and the bark rooting rate are both minimum values, which shows that river sand is most favorable for the root taking of the bark of the hard branch of the slippery elm as a cutting medium, and turf: the perlite-2: 1 mixed matrix is more beneficial to the rooting of the bark, and the turf: vermiculite: the rooting condition of the perlite mixed matrix and the vermiculite bark part is relatively moderate, and the pure grass carbon is most unfavorable for the rooting of the ulmus davidiana dura mater bark part.

TABLE 7 influence of the substrate type on the various cuttage indices

By combining the experimental examples 1-4, as can be seen from the analysis tables 8-1 to 8-4 of the optimal conditions of the ulmus davidiana hardwood cutting, the type of the matrix is the first influence factor of the survival rate, the number of roots, the length of the roots, the time of the roots, the length of the branches and the number of leaves of the ulmus davidiana hardwood cutting, namely, the influence degree on each index of the cutting is the maximum.

The hormone concentration is the first factor of the callus time, the second factor of the cuttage survival rate, the rooting number and the branch length, the third factor of the root length, the rooting time and the leaf number, and the comprehensive influence is only second to the matrix type.

The hormone type is the second influence factor of root length, callus time, rooting time and leaf number, the third influence factor of survival rate and rooting number, the fourth influence factor of branch length, and the comprehensive influence is arranged in the third place.

The processing time is the third influence factor of the branch length and the rooting time, and the fourth influence factor of the survival rate, the number of rooting strips, the root length, the callus time and the number of leaves, and the influence degree of each index of cuttage is small, namely the comprehensive influence is the weakest.

By combining the analysis results and comprehensively considering actual operation, the optimal cuttage combination can be screened out to be A5B5C3D5, namely IBA +800 mg/L + treatment for 30min + grass carbon, vermiculite, perlite and mixed matrix of 3:1: 0.1.

TABLE 8-1 analysis of optimal conditions for hardwood cutting of Ulmus davidiana

TABLE 8-2 analysis of optimal conditions for hard-wood cutting of Ulmus davidiana var

TABLE 8-3 analysis of optimal conditions for hard-wood cutting of Ulmus davidiana var

TABLE 8-4 analysis of optimal conditions for hardwood cutting of Ulmus davidiana

Claims

1. A method for rapid cuttage and breeding of hard branches of Ulmus davidiana var comprises the steps of (1) selecting a stock plant with excellent growth vigor before sprouting of Ulmus davidiana var, collecting annual robust branches, cutting off branches with branch spines, branch bases with the thickness larger than 1cm and branch tips smaller than 0.35cm, (2) cutting and cutting, cutting the branches pretreated in the step (1) into 3-5 buds and cutting slips with the length of 8-10 cm, bundling a plurality of cutting slips according to the specification of a plug tray, soaking in 1000 times of 50% carbendazim wettable powder for 30min for sterilization, (3) preparing a cutting medium and a rooting agent, mixing turf, vermiculite, perlite, namely 30:10:1, serving as the cutting medium, filling the cutting medium into a plug tray, disinfecting with 800 mg/L high-temperature solution, preparing a rooting agent, wherein the rooting agent is IBA800 mg/L solution, treating the base of the obtained in the step (2) 3cm, 30: 4 min, opening a shading solution in a shading and transplanting box, sterilizing the middle of the planting slip, transplanting the seedling after 10% of the cuttage, and transplanting the root system is opened, wherein the rooting agent is used for sterilization after the seedling transplanting, the rooting agent is used for sterilization after the seedling transplanting, the seedling transplanting is soaked in a seedling transplanting, the seedling transplanting is carried out after the seedling transplanting, the seedling transplanting is carried out after the seedling transplanting, the seedling transplanting is carried out after the seedling transplanting is carried out, the seedling transplanting is carried out after the seedling transplanting, the seedling transplanting is carried.

2. The method for rapid cutting propagation of ulmus davidiana var.davidiana var.dav.

3. The method for rapid cutting propagation of ulmus davidiana var, according to claim 2, wherein the hole drilled in the hole disc in the step (3) has a depth of 3cm and a diameter of 1 cm.

4. The method for rapid cutting propagation of ulmus davidiana var as claimed in claim 1, wherein the foliar fertilizer used in step (5) is 0.1% monopotassium phosphate or urea.