Seedling growing method for xanthoceras sorbifolia bunge current-year seedlings

Abstract

The invention discloses a method for growing seedlings of xanthoceras sorbifolia bunge in the current year, and belongs to the technical field of xanthoceras sorbifolia bunge seedlings. The seedling raising method comprises the following steps: (1) cultivating rootstock seedlings; (2) stock seedling management; (3) scion collection; (4) grafting; (5) performing post-grafting management: performing germination accelerating and sowing on xanthoceras sorbifolia bunge seeds in the current year of harvesting, performing overwintering cultivation of stock seedlings in a shed, and performing management modes of spraying a nutrient solution and chlormequat chloride in the next year, so that the stock seedlings are consistent with nursery stock scions in a cutting orchard in phenological time at the end of May, the growth amount and the thickness are completely matched with scions, grafting is facilitated, and the survival rate is high; the seedlings can be outplanted in the same year after grafting survival. The method is easy and convenient to operate and small in space-time limitation, the seedling raising period is shortened to one year from 2-3 years of a traditional method, the ground diameter of grafted seedlings can reach 1 cm during outplanting in the current year of grafting, the grafting survival rate reaches 90% or above, and popularization is easy.

Description

Technical Field

[0001] The invention relates to the technical field of Xanthoceras sorbifolia seedling cultivation, and more particularly to a method for cultivating Xanthoceras sorbifolia seedlings in the same year. Background Art

[0002] Xanthoceras sorbifolium Bunge, a deciduous shrub or small tree of the Sapindaceae family and Xanthoceras sorbifolium genus, is a woody oil-bearing tree species unique to my country, mainly distributed in Gansu, Shaanxi, Inner Mongolia, Liaoning and Shandong. Xanthoceras sorbifolia has a wide range of application values ​​in food, medicine, and greening barren hills. In particular, the oil content of its seeds is between 30% and 50%, and the oil content of its kernels is as high as 65%. It can not only be used to make edible oil, but also as a raw material for preparing biodiesel.

[0003] However, due to the low utilization rate of improved varieties and the lack of efficient and reliable breeding methods, low yield and low efficiency have become bottlenecks in the development of the Xanthoceras sorbifolia industry. The propagation methods of Xanthoceras sorbifolia include tissue culture, seed seedling propagation and grafting. However, due to the high cost of tissue culture, its large-scale use is often restricted in practice, so seed seedling propagation and grafting have become common propagation methods for Xanthoceras sorbifolia. For example, most new Xanthoceras sorbifolia plantations are bred from seed seedlings. However, the genetic material of seed seedlings will undergo recombination and mutation and cannot completely maintain the excellent characteristics of the mother tree, which makes the large-scale promotion of seed seedlings risky. Therefore, excellent varieties of Xanthoceras sorbifolia are often selected through grafting propagation to stably and efficiently achieve fixed excellent traits and large-scale propagation, so as to meet the demand for asexual propagation of high-quality seedlings for large-scale industrialization of Xanthoceras sorbifolia.

[0004] Patent CN101627713A Xanthoceras sorbifolia seedling raising technology discloses bud grafting with large pieces of xylem, breeding stock seedlings in the first year, selecting seedlings with a diameter of more than 1 cm as stock in late April of the second year after one year of growth, selecting high-yield and robust branches as scion grafting, waiting for buds to grow and develop after grafting, and finally meeting the conditions for transplanting. The above technical solution takes one year to cultivate stock seedlings, and it takes nearly one and a half years to grow to mature seedlings after grafting, so the seedling raising cycle is relatively long. CN105917974A A method for breeding container seedlings of grafted Xanthoceras sorbifolia seedlings, which discloses the seedling raising steps of "1. Cultivation of seedlings, a. Selecting seeds, b. Storing seeds, c. Germination; 2. Selecting branches for scions; 3. Grafting, a. Raising rootstocks, b. Cutting scions, c. Cutting rootstocks, d. Grafting; 4. Planting and management of grafted seedlings". However, when grafting in spring and summer, the seed seedlings have not yet reached the required thickness for grafting and cannot match the scions, resulting in strict scion screening and low grafting survival rate. In addition, when the seedlings stop growing in autumn, the ground diameter is less than 6mm, the growth cycle is short, and the growth is weak; if grafted in autumn, the grafted seedlings need to grow into seedlings in the second year to meet the requirements for transplanting, and there is still the defect of a long seedling raising cycle.

[0005] Therefore, it is of great significance to provide a method for raising seedlings of Xanthoceras sorbifolia in the same year, which can not only ensure the survival rate but also shorten the seedling raising period so that the seedlings can be planted in the same year. Summary of the invention

[0006] In view of the above problems, the present invention provides a method for raising seedlings of Xanthoceras sorbifolia in the same year.

[0007] In order to achieve the above object, the present invention adopts the following technical solution:

[0008] A method for raising seedlings of Xanthoceras sorbifolia in the current year comprises the following steps:

[0009] (1) Cultivation of rootstock seedlings:

[0010] In mid-to-late July, fully mature Xanthoceras sorbifolia fruits were harvested, and seeds with full grains and uniform size were selected. After natural drying, they were stored in a dry and ventilated environment at 4°C until late October, and then taken out and soaked in 45°C warm water for 4-8 hours. During this period, cracked seeds were selected and sown in seedling bags, and then moved to a greenhouse for seedling raising.

[0011] (2) Rootstock seedling management:

[0012] From late November to mid-December, after the rootstock seedlings germinate, adjust the temperature and soil humidity in the greenhouse for wintering cultivation;

[0013] In March of the second year, after the rootstock seedlings are semi-lignified, thinning is carried out, leaving one Xanthoceras sorbifolia seedling with the best growth in each bag, and the remaining rootstock seedlings are moved to nutrient pots, one plant per pot; irrigate the roots of each seedling with nutrient solution once in early and mid-April; irrigate the roots of each seedling with dwarfing agent once in early and late May;

[0014] (3) Scion collection:

[0015] From mid-to-late May to early June of the second year, collect the current-year scion from the mother tree of the excellent Xanthoceras sorbifolia variety in the suitable habitat, which is ≥10 cm long, has full bud development, and is free of diseases and insect pests. Cut off the leaves and leave a 0.8-1.2 cm long petiole as the scion;

[0016] (4) Grafting:

[0017] In mid-June of the second year, the buds with woody parts on the scion were removed by using the T-shaped three-knife bud removal method, and rootstock seedlings with a stem diameter of 0.4cm to 0.7cm were selected for grafting. After the grafting was completed, the interface was tied and untied after 15 days.

[0018] (5) Post-grafting management:

[0019] After the grafted buds sprout, remove them in time and wipe off all the buds on the rootstock except the grafted buds. When the grafted seedlings grow to a ground diameter ≥1cm, they can be transplanted.

[0020] Preferably, the sowing in step (1) is as follows: 2-3 seeds are placed in each seedling bag, the sowing depth is 4cm to 5cm, the soil is covered to a depth of 2cm to 3cm and compacted, and watering is performed until water seeps out from the bottom of the seedling bag.

[0021] Preferably, the nutrient solution in step (2) is composed of the following components based on the total mass of 100%: 0.2% urea, 0.6% ammonium phosphate and 1% potassium dihydrogen phosphate, and the rest is water; the application amount of the nutrient solution each time is 20 ml / plant.

[0022] Preferably, the concentration of chlormequat in step (2) is 100 mg / L, and the application amount is 20 ml / plant each time.

[0023] Preferably, the grafting in step (4) is specifically as follows: a 4-6 mm transverse cut is made at a smooth part of the stock seedling 5 cm above the ground and reaches the xylem, a 4-6 mm longitudinal cut is made downward in the middle of the transverse cut and reaches the xylem, the bud is placed in the cut of the stock and pushed downward so that the transverse cut of the bud is aligned with the transverse cut of the stock.

[0024] Through the above technical solutions, it can be known that the present invention discloses a method for raising seedlings of Xanthoceras sorbifolia in the same year. The present invention germinates and sows Xanthoceras sorbifolia seeds in the year of harvest, cultivates rootstock seedlings in a shed overwintering, and adopts management methods such as spraying nutrient solution and dwarfing agent in the next year, so that the rootstock seedlings are consistent with the phenological time of the seedling scion in the scion nursery at the end of May, the growth amount and thickness are completely matched, the scion is convenient for grafting and excision, the survival rate is high, and the grafted scion can be transplanted in the same year after survival.

[0025] The seedling raising method of the present invention shortens the seedling raising period from 2-3 years of the traditional method to 1 year, and the ground diameter of the grafted seedlings can reach 1 cm when they are transplanted in the year of grafting, which can ensure high seedling quality and transplant survival rate, and improve land utilization rate and capital utilization rate. The method is easy to operate, has little time and space restrictions, and the grafting survival rate is as high as more than 90%, which is easy to promote. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 : Germination diagram of rootstock seedlings after sowing Xanthoceras sorbifolia seeds in seedling bags;

[0027] Figure 2 : Wintering situation of Xanthoceras sorbifolia rootstock seedlings;

[0028] Figure 3 : Picture of thinning of Xanthoceras sorbifolia rootstock seedlings;

[0029] Figure 4 : Picture of the state of Xanthoceras sorbifolia rootstock seedlings before grafting, stem thickness 0.4cm~0.7cm;

[0030] Figure 5 : Picture of Xanthoceras sorbifolia after grafting;

[0031] Figure 6 : Diagram of untying the grafting point of Xanthoceras sorbifolia grafted seedlings. DETAILED DESCRIPTION

[0032] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0033] The reagents involved in the embodiments of the present invention are all purchased from commercial channels, and the methods not mentioned are conventional experimental methods and will not be described in detail here.

[0034] Example 1

[0035] A method for raising seedlings of Xanthoceras sorbifolia in the current year comprises the following steps:

[0036] (1) In mid-to-late July 2023, fully mature Xanthoceras sorbifolia were harvested, and high-quality seeds of the year with full, uniform grains and fully mature seeds were selected as seeds for rootstock seedling cultivation. After harvesting, they were naturally dried and stored at 4°C in a dry and ventilated storage location.

[0037] In late October 2023, the seeds were taken out and soaked in 45°C warm water for 4-8 hours. During this period, cracked seeds were selected and sown in seedling bags. 2-3 seeds were placed in each seedling bag. The sowing depth was 4cm~5cm. The soil was covered to a depth of 2cm~3cm and then compacted. After sowing, water was applied until water seeped out from the bottom of the seedling bag. A total of 263 seedling bags were sown.

[0038] (2) Move the seedling bags into the greenhouse for seedling cultivation, and keep the greenhouse exposed to natural light. On November 13, 2023, the rootstock seedlings began to germinate (see Figure 1 ), maintain the minimum temperature of greenhouse soil ≥10℃, soil moisture content 15-20%, natural light, and carry out wintering cultivation until February 19, 2024. 715 plants have sprouted, with a germination rate of 90.62%, among which the rootstock seedlings with the thickest ground diameter can reach 3-4mm ground diameter (see Figure 2 );

[0039] On March 18, 2024, the rootstock seedlings were semi-lignified. Thinning began on the same day, and the best-growing Xanthoceras sorbifolia seedlings were selected. One plant was kept in each seedling bag, and the remaining rootstock seedlings were moved to nutrient pots, one plant per pot (see Figure 3 );

[0040] On April 4, 2024, 20 ml of nutrient solution (nutrient solution concentration (m / m%): 0.2% urea + 0.6% ammonium phosphate + 1% potassium dihydrogen phosphate) was applied to the roots of each rootstock seedling once, and sprayed for the second time on April 15, and the application method was the same as the first time; on May 1, 20 ml of dwarfing agent (concentration 100 mg / L) was applied to the roots of each rootstock seedling once, and sprayed for the second time on May 15, and the application method was the same as the first time.

[0041] (3) On June 2, 2024, collect the current-year scion of Xanthoceras sorbifolia from the mother trees of the superior varieties in the suitable habitat, which is ≥10 cm long, has full bud development, and is free of diseases and insect pests. Cut off the leaves and leave a 0.8-1.2 cm long petiole as the scion (if not grafted on the same day, low temperature and moisturizing are required, and the grafting should be completed within 1 week);

[0042] (4) Select rootstock seedlings with a diameter of 0.4 cm to 0.7 cm (see Figure 4 ), make a 4-6mm long horizontal cut at a smooth part 5cm from the ground, and then make a 4-6mm long vertical cut downwards in the middle of the horizontal cut, with the horizontal and vertical cuts reaching the woody part, and the two cuts are T-shaped; use the T-shaped three-knife bud removal method to remove the woody bud on the scion, put the bud into the cut of the rootstock, and push it downward to align the horizontal cut of the bud with the horizontal cut of the rootstock; tie the interface after the grafting with a plastic strip (see Figure 5 ), unbind after 15 days (see Figure 6 ).

[0043] (5) Remove the buds promptly after they sprout, and wipe off all buds on the rootstock except the buds. According to statistics, a total of 256 grafted plants were grafted, 240 survived, and the survival rate was 93.75%. By the end of September 2024, most of the grafted seedlings can grow to a ground diameter greater than 1 cm and can be transplanted, or transplanted with pots in the spring of the following year.

[0044] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0045] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for raising seedlings of Xanthoceras sorbifolia in the current year, characterized in that: The following steps are involved: (1) Cultivation of rootstock seedlings: In mid-to-late July, fully mature Xanthoceras sorbifolia fruits were harvested, and seeds with full grains and uniform size were selected. After natural drying, they were stored in a dry and ventilated environment at 4°C until late October, and then taken out and soaked in 45°C warm water for 4-8 hours. During this period, cracked seeds were selected and sown in seedling bags, and then moved to a greenhouse for seedling raising. (2) Rootstock seedling management: From late November to mid-December, after the rootstock seedlings germinate, adjust the temperature and soil humidity in the greenhouse for wintering cultivation; In March of the second year, after the rootstock seedlings are semi-lignified, thinning is carried out, leaving one Xanthoceras sorbifolia seedling with the best growth in each seedling bag, and the remaining rootstock seedlings are moved to nutrient pots, one plant per pot; irrigate the roots of each seedling with nutrient solution once in early and mid-April; irrigate the roots of each seedling with dwarfing agent once in early and late May; (3) Scion collection: From mid-to-late May to early June of the second year, collect the current-year scion from the mother tree of the excellent Xanthoceras sorbifolia variety in the suitable habitat, which is ≥10 cm long, has full bud development, and is free of diseases and insect pests. Cut off the leaves and leave a 0.8-1.2 cm long petiole as the scion; (4) Grafting: In mid-June of the second year, the buds with woody parts on the scion were removed by using the T-shaped three-knife bud removal method, and rootstock seedlings with a stem diameter of 0.4cm to 0.7cm were selected for grafting. After the grafting was completed, the interface was tied and untied after 15 days. (5) Post-grafting management: After the grafted buds sprout, remove them in time and wipe off all the buds on the rootstock except the grafted buds. When the grafted seedlings grow to a ground diameter ≥1cm, they can be transplanted.

2. The method for raising seedlings of Xanthoceras sorbifolia in the current year according to claim 1, characterized in that: The sowing in step (1) is as follows: 2-3 seeds are placed in each seedling bag, the sowing depth is 4cm-5cm, the soil is covered to a depth of 2cm-3cm and compacted, and watering is performed until water seeps out from the bottom of the seedling bag.

3. The method for raising seedlings of Xanthoceras sorbifolia in the current year according to claim 1, characterized in that: The conditions for the overwintering culture in step (2) are: ground temperature ≥ 10°C, natural light, and soil moisture content of 15-20%.

4. The method for raising seedlings of Xanthoceras sorbifolia in the current year according to claim 1, characterized in that: The nutrient solution in step (2) is composed of the following components based on the total mass of 100%: 0.2% urea, 0.6% ammonium phosphate and 1% potassium dihydrogen phosphate, and the remainder is water; The amount of the nutrient solution applied each time was 20 ml / plant.

5. The method for raising seedlings of Xanthoceras sorbifolia in the current year according to claim 1, characterized in that: The concentration of chlormequat in step (2) is 100 mg / L, and the application amount is 20 ml / plant each time.

6. The method for raising seedlings of Xanthoceras sorbifolia in the current year according to claim 1, characterized in that: The grafting in step (4) is specifically as follows: a 4-6 mm horizontal cut is made at a smooth part of the stock seedling 5 cm above the ground and reaches the xylem, a 4-6 mm vertical cut is made downward in the middle of the horizontal cut and reaches the xylem, a bud is placed in the cut of the stock and pushed downward so that the horizontal cut of the bud piece is aligned with the horizontal cut of the stock.

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