A method for growing actinidia arguta

Abstract

This invention discloses a method for cultivating hardy kiwifruit, comprising the following steps: S1 Cultivating male 'Jinmi Rootstock No. 1' seedlings; S2 Grafting, starting in mid-to-late February, high-position grafting is performed on the 'Jinmi Rootstock No. 1'; First, a grafting method with a grafting diameter of 0.8 cm is used: the scion is 5-7 cm long, each segment retains 2-3 buds, and the lower end is cut into an oblique surface; the rootstock is cut at a diameter of 0.8 cm, then longitudinally cut, with the cut size similar to that of the scion; then the cambium layers of the scion and rootstock are aligned and tied tightly with a thin film strip. Beneficial effects: 'Jinmi Rootstock No. 1' can increase the average yield of hardy kiwifruit cultivars by 25.7%, showing a significant yield increase; 'Jinmi Rootstock No. 1' has a very well-developed root system, strong vitality, and can be directly propagated by cuttings, making seedling cultivation easy; it improves the adaptability of hardy kiwifruit cultivation and reduces the rate of tree death caused by waterlogging.

Description

Technical Field

[0001] This invention relates to the field of fruit tree cultivation technology, specifically a method for planting hardy kiwifruit. Background Technology

[0002] In recent years, with the improvement of people's living standards and changes in consumer tastes, a type of hardy kiwifruit (A. arguta (Sieb. & Zucc.) Planch. ex Miq.) has been widely introduced and cultivated throughout China. This species is highly differentiated and widely distributed, ranging from the northernmost Heilongjiang River to the Wuling Mountains in Guangxi in the south, growing in mixed forests or mixed forests with sufficient moisture. Currently, there are nearly 200,000 mu (approximately 13,333 hectares) of kiwifruit cultivated nationwide, with a yield of 32,000 tons. Of this, about 100,000 mu (approximately 6,667 hectares) are in the northeastern provinces of China, and nearly 100,000 mu (approximately 6,667 hectares) are in other major kiwifruit producing provinces (municipalities and autonomous regions).

[0003] Hardy kiwifruit was first cultivated on a large scale in Northeast China. The main varieties are primarily green-fruited (with green skin and flesh when ripe), adapted to the low temperatures of Northeast China, but intolerant of the high temperatures and humidity of southern China. Propagation is mainly achieved through hardwood cuttings or tissue culture. With the increasing economic benefits of hardy kiwifruit cultivation, it can be harvested and eaten immediately without post-ripening, maturing in early to mid-August, making it readily available and advantageous for orchards near cities, resulting in significant economic gains. In contrast, Chinese kiwifruit varieties require a 5-7 day post-ripening period before consumption, with the earliest maturity generally in late August or early September. In recent years, when hardy kiwifruit was introduced to major kiwifruit-producing provinces (municipalities, and autonomous regions) in China, it was found that the Northeast hardy kiwifruit varieties were not adapted to the hot and rainy conditions of the south, resulting in leaf and fruit drop and cultivation failures.

[0004] In recent years, the kiwifruit team at the Fruit and Tea Research Institute of the Hubei Academy of Agricultural Sciences has screened a series of high-quality, early-maturing new varieties from natural hybrid populations of wild hardy kiwifruit in mountainous areas at an altitude of about 1,000 meters in Wufeng County, Yichang City, Hubei Province. Three of these new hardy kiwifruit varieties have obtained plant variety protection rights. These new varieties have a soluble solids content of 18-20%, mature in early to mid-August, and have a purplish-red peel and flesh when ripe, allowing them to be eaten immediately without further ripening. They are suitable for artificial cultivation. Besides being widely cultivated in the cold regions of Northeast China, hardy kiwifruit is mainly propagated asexually through hardwood cuttings or tissue culture. Kiwifruit trees propagated through these methods have less prominent taproots, underdeveloped lateral and fibrous roots, and their ability to grow vegetatively and synthesize growth hormones such as ABA and ethylene is relatively poor compared to seed-propagated seedlings, resulting in lower stress resistance. Because of the small size of the seeds, the low number of seeds in the fruit, the low germination rate, and the limited seed source, the hardy macaque is generally not used for seed propagation as rootstock in production.

[0005] Chinese patent application publication number CN 113785732 A discloses a method for cultivating southern hardy kiwifruit. The method involves grafting hardy kiwifruit onto a Chinese kiwifruit cultivar, resulting in a tree structure with one main trunk and two lateral vines. One lateral vine is from the hardy kiwifruit variety, and the other is from the Chinese kiwifruit cultivar, arranged in opposite directions along the rows. This technique allows two different kiwifruit species to benefit from each other, ensuring the yield of the hardy kiwifruit variety and achieving higher economic benefits, while also preventing sudden death during peak production. However, because these are two different kiwifruit varieties with different phenological and ripening periods, it is not conducive to normal cultivation management of the kiwifruit tree and fruit harvesting. Summary of the Invention

[0006] To address the aforementioned technical problems, this invention provides a method for adapting the hardy kiwifruit to cultivation in southern regions.

[0007] The technical solution of this invention is:

[0008] A method for cultivating hardy kiwifruit includes the following steps:

[0009] S1 cultivates male 'Jinmi Rootstock No. 1' kiwifruit variety;

[0010] In January and February, in conjunction with winter pruning, cut branches from male 'Jinmizhen No. 1' kiwifruit plants, selecting branches with a diameter of 0.8cm or more and a length of 15cm, and then store them in sand.

[0011] Clean river sand should be used. Bundle 50 branches together, with a 5 cm thick layer of sand at the bottom, and pile them in the nursery room. Then, wet the bundles of branches and pile them up in a single layer. Sprinkle another 5 cm of sand on top of the branches. The pile height should not exceed 1 m. The area of ​​the sand in the room should be determined according to the size of the nursery room to facilitate manual operation and management.

[0012] After piling them up, cover the sand with a 5cm layer of straw, and then cover the straw with a layer of mulch to retain moisture.

[0013] Remove the plastic film and straw every 15 days to check the dryness and wetness of the sand and straw. If the sand and straw are dry, spray water finely with a spray bottle to keep the sand moist.

[0014] From late February to mid-March, take out the branches stored in sand and soak them in ABT No. 1 rooting powder at a concentration of 100 ppm for 3-4 hours, with a soaking length of 5 cm for the lower part of the branches.

[0015] Seedlings are propagated by cuttings in a greenhouse. The seedbed is 1 meter wide. 1 kg of high-quality compound fertilizer is applied as base fertilizer for every 10 meters of seedbed length. The seedbed is then watered until the soil moisture reaches 10 cm. A 1.5-meter wide black plastic film is then laid over the seedbed. Cuttings are then inserted through the film, with each cutting measuring 10 cm in length and width.

[0016] Strengthen fertilizer and water management in normal times. In June, insert bamboo poles with a thickness of 2cm and a length of 1m at 50cm intervals on both sides of each seedbed. Place one pole every 5m and tie it with thin hemp rope. Pull two poles for each seedbed. Fix one thin hemp rope at 50cm from the bamboo pole. When the seedlings grow to 50cm, fix them to the thin hemp rope.

[0017] S2 grafting

[0018] In January of the following year, the 'Golden Kiwi Rootstock No. 1' was directly used for field planting of calyx kiwifruit, and high grafting of calyx kiwifruit began in mid-to-late February.

[0019] First, select a grafting point with a diameter of 0.8 cm and use the cleft grafting method:

[0020] It is best to select one-year-old soft-fleshed kiwifruit 'Jinxianghong' branches as scions. The scions should be 5-7 cm long, with 2-3 buds left on each section, and the lower end should be cut into an oblique shape.

[0021] The rootstock is cut at a thickness of 0.8 cm, and then longitudinally cut, with the cut size similar to that of the scion.

[0022] Then align the cambium layers of the scion and rootstock and tie them tightly with a film strip;

[0023] In early to mid-June, when the 'Jinxianghong' section of the hardy kiwifruit to be grafted grows to 50 cm, the tip is pinched off to encourage the new branches of 'Jinxianghong' to become semi-lignified.

[0024] After the grafting is successful, strengthen the management of the seedlings to allow them to grow, trellise them, establish orchards, and promptly prune the seedlings that grow from the 'Golden Kiwi Rootstock No. 1' kiwi to ensure that the grafted branches are properly trellised and put into production in a timely manner.

[0025] Beneficial effects: "Jinmi Rootstock No. 1" can increase the yield of hardy kiwifruit cultivars by an average of 25.7%, showing a significant yield increase. "Jinmi Rootstock No. 1" has a very well-developed root system and strong vitality, and can be directly propagated by cuttings, making seedling cultivation easy; it improves the adaptability of hardy kiwifruit cultivation and reduces the rate of tree death caused by waterlogging. Detailed Implementation

[0026] For rapid experimental observation and biological research (mainly guiding principles), three grafting experiments and treatment cultivation production studies were conducted on the new hardy kiwifruit variety "Jinxianghong":

[0027] Experiment location: Nanhe Village, Wufeng County, Yichang City, Hubei Province, at an altitude of 1000 meters.

[0028] Climate and soil conditions: average annual temperature 12.8℃, average annual precipitation around 1400 mm, yellow-brown soil, pH 5.0-6.5, acidic or slightly acidic, conventional management.

[0029] Experimental varieties and areas: The tree row spacing was 4 meters, the plant spacing was 3 meters, and the trees were 3 years old. The experimental area was 20 mu of the delicious Chinese kiwifruit variety "Jin Kui" as rootstock; the experimental area of ​​the soft-fleshed kiwifruit variety "Longcheng No. 1" as rootstock was 20 mu; and the experimental area of ​​"Jinmizhen No. 1" as rootstock, which was bred from male calyx kiwifruit plants, was 20 mu.

[0030] Grafting time, method and treatment: Grafting time is in late February before sap flow. Single bud branch grafting is performed at a high position of about 60-80 cm above the ground. Two buds are grafted on each experimental tree. The two buds should be grafted facing each other and the distance between the two grafted buds should be between 10-20 cm. The soft-fleshed kiwifruit variety "Jinxianghong" is used for the experiment.

[0031] Sixty plants of each variety were tested, and the survival rate and germination rate were recorded after grafting.

[0032] One method involved grafting the new hardy kiwifruit variety "Jinxianghong" onto "Jinkui" as rootstock. After successful grafting, the trees grew and developed normally, generally flowering and fruiting in the second year and producing abundant fruit in the third. However, after fruiting, the entire tree (branches, trunk, and root system) died, with a mortality rate exceeding 80%, impacting research results and widespread application. In the fourth year (2021), when "Jinxianghong" was grafted onto Chinese kiwifruit, statistics on May 25th showed that all the "Jinxianghong" trees grafted onto the experimental trees died, including the root system of the original Chinese kiwifruit rootstock, and the main trunk withered. Analysis of the causes: While the Chinese kiwifruit tree and rootstock are of the same species, and the hardy kiwifruit (Actinidia arguta) are different species within the same genus, the Chinese kiwifruit grafted onto one side has normal leaves for photosynthesis, allowing for normal transport to the roots and maintaining the original Chinese kiwifruit's growth and development. However, because these are two different kiwifruit varieties with different phenological and ripening periods, it is detrimental to the normal cultivation management of the kiwifruit tree and fruit harvesting. The hardy kiwifruit variety on the other side, besides the grafted leaves being able to photosynthesize to meet its own growth needs, also requires the synthesis and transport of growth hormones such as ABA and ethylene from the roots to ensure its normal growth. If the original Chinese kiwifruit variety on the main trunk is completely removed, the original roots and root system lose their primary nutrient supply. The nutrients produced by the hardy kiwifruit variety through photosynthesis are not adapted to the original Chinese kiwifruit roots, causing the original Chinese kiwifruit roots to starve and ultimately leading to the death of the entire tree.

[0033] Secondly, jujube trees were directly grafted onto the rootstock of the Northeast variety "Longcheng No. 1" clonal hardwood cuttings. Kiwifruit "Gold" "Xiang Hong" New variety trials revealed that the kiwifruit is susceptible to high temperatures and drought, as well as waterlogging. The trees exhibit weak growth, low fruit yield, and poor quality. The main reason for this is that kiwifruit trees propagated through hardwood cuttings or tissue culture have underdeveloped taproots, lateral roots, and fibrous roots. Their ability to grow vegetatively and synthesize growth hormones such as ABA and ethylene is relatively weaker compared to seed-propagated seedlings, resulting in lower stress resistance. Furthermore, the hardy kiwifruit variety is generally not used for rootstock propagation due to its small seeds, low seed count, low germination rate, and limited seed supply.

[0034] Third, jujube was directly grafted onto the superior rootstock line "Jinmi Rootstock No. 1" selected from male kiwifruit plants. macaques Peach "Golden Fragrance Red" The new variety trial was primarily conducted because both *Actinidia calycifolia* and *Actinidia arguta* belong to the *Actinidia* genus, specifically the fruit section. The "Golden Kiwi Rootstock No. 1" has woody roots, is resistant to waterlogging, and has a well-developed root system with strong taproot support. Its root depth exceeds that of *Actinidia chinensis* and *Actinidia deliciosa* seedling rootstocks by 35.9%, making it more resistant to waterlogging and increasing yield by 27.9%. It is suitable for planting in orchards with high humidity and prone to water accumulation, and also significantly improves fruit quality, making it the preferred rootstock for waterlogging resistance in kiwifruit. The "Golden Kiwi Rootstock No. 1" can improve the yield of *Actinidia arguta*. kiwi cultivation The average yield of the variety increased by 25.7%, demonstrating a significant increase in production. "Jinmi Rootstock No. 1" has a very well-developed root system and strong vitality, allowing for easy propagation through direct cuttings. It improves the adaptability of hardy kiwifruit cultivation, reduces tree mortality caused by waterlogging, significantly enhances drought resistance, reduces irrigation, and conserves water resources. It also improves stress resistance, thereby increasing the kiwifruit's resistance to diseases such as bacterial canker, reducing the frequency of chemical control and ensuring the safety of kiwifruit for consumption. Furthermore, it improves fruit quality, enhances the international competitiveness of my country's kiwifruit industry, and promotes its upgrading and sustainable development. Recent fruit-bearing observations also show excellent performance in resistance to continuous cropping and poor soil conditions.

[0035] This invention has developed a cultivation and production method for hardy kiwifruit, which can effectively improve the cultivation and production of hardy kiwifruit, with a survival rate of over 97.9%, vigorous tree growth, and fruiting in the fourth year. This method can accelerate the widespread promotion and application of new hardy kiwifruit varieties.

[0036] On March 9, 2018, the first year of grafting the hardy kiwifruit 'Jinxianghong' onto rootstocks such as 'Jinkui', 'Longcheng No. 1', and 'Jinmizhen No. 1', no flowering or fruiting was observed. There were no significant differences in the survival rate (%) of the experimental trees and the control trees on April 9, May 9, and June 9 of the same year.

[0037] Table 1: First-year survival rate of grafted 'Jinxianghong' kiwifruit (2018)

[0038]

[0039] In 2019, the second year after the hardy kiwifruit 'Jinxianghong' was grafted onto rootstocks such as 'Jinkui', 'Longcheng No. 1' and 'Jinmizhen No. 1', there were no significant differences in the survival rate (%) of the experimental trees and the control trees on April 9, May 20, and June 9.

[0040] Table 2: Performance of the grafted 'Jinxianghong' Soft-fleshed Kiwifruit in the second year (2019)

[0041]

[0042] In 2020, the third year after the 'Jinxianghong' kiwifruit variety was grafted onto rootstocks such as 'Jinkui', 'Longcheng No. 1', and 'Jinmizhen No. 1', the survival rate (%) of the experimental and control trees was recorded on April 9, the average fruit weight (g) on ​​August 15, and the soluble solids (%) measured using a handheld saccharimeter on August 20. The survival rate of the control trees was significantly higher than that of the experimental trees. The survival rate of the three varieties in the experimental trees was less than 50%. In the other two aspects, the average single fruit weight (g) and the soluble solids (%) of the experimental trees were lower than those of the control trees, but the differences were not significant.

[0043] Table 3: Performance of the grafted 'Jinxianghong' Soft-fleshed Kiwifruit in its third year (2020)

[0044]

[0045] The performance of the hardy kiwifruit 'Jinxianghong' grafted onto rootstocks such as 'Jinkui,' 'Longcheng No. 1,' and 'Jinmizhen No. 1' in its fourth year (2021) was as follows: On May 25th, statistics showed that all the hardy kiwifruit 'Jinxianghong' grafted onto the 'Jinkui' rootstock died, including the root system of the original Chinese kiwifruit rootstock, and the main trunk withered. Analysis of the cause: The Chinese kiwifruit tree and rootstock are of the same species. Removing the Chinese kiwifruit varietal from the original main trunk deprives the original root system of its native nutrients. The hardy kiwifruit varietal, through photosynthesis, transfers various nutrients to the original Chinese kiwifruit root system, which is unsuitable, causing the original Chinese kiwifruit root system to starve and ultimately leading to the death of the entire tree.

[0046] Table 4: Performance of the 'Jinxianghong' hardy kiwifruit in its fourth year of grafting (2021)

[0047]

[0048] Based on the typical planting density of kiwifruit orchards (row spacing 4 meters, plant spacing 3 meters), the yield of the hardy kiwifruit variety "Jinxianghong" in the trial reached approximately 400 kg per mu (0.067 hectares) in the fourth year. Over the past three years, the ex-orchard price of "Jinxianghong" has remained stable at around 100 yuan / kg, with an average output value of around 40,000 yuan / mu; while the average price of cultivated Chinese kiwifruit is around 20 yuan / kg, with an average output value of around 20,000 yuan / mu. The economic benefits of hardy kiwifruit planted using "Jinmizhen No. 1" rootstock are more than double those of Chinese kiwifruit. Furthermore, new varieties like "Jinxianghong" mature earlier, in early to mid-August, allowing for immediate harvesting and consumption, reducing the post-ripening stage. This further enhances their economic benefits beyond urban agricultural picking activities in suburban areas.

[0049] The new hardy kiwifruit varieties such as "Jinxianghong" planted using "Jinmizhen No. 1" as rootstock have a wide range of adaptability, from southern to northern China. In recent years, for example, in Shandong, where Chinese kiwifruit varieties were not originally suitable for planting, the new hardy kiwifruit varieties have been widely promoted. They can also be planted at high altitudes of about 1000-1500 meters, while Chinese kiwifruit is generally not suitable for large-scale planting in areas above 1000 meters in altitude and in northern provinces and cities.

[0050] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A method for cultivating hardy kiwifruit, characterized in that, Includes the following steps: S1 cultivates male 'Jinmi Rootstock No. 1' kiwifruit variety; In January and February, in conjunction with winter pruning, cut branches from male 'Jinmizhen No. 1' kiwifruit plants, selecting branches with a diameter of 0.8cm or more and a length of 15cm, and then store them in sand. Use clean river sand. Bundle the branches together in groups of 50, and lay a 5 cm thick layer of sand at the bottom. Store the bundles in the nursery. Then, soak the branches and pile them up in a single layer, then sprinkle 5 cm of sand on top of the branches, and pile them up to a certain height. The area of ​​the sand in the room should not exceed 1 m, and the area of ​​the sand should be set according to the size of the seedling room to facilitate manual operation and management. After piling them up, cover the sand with a 5cm layer of straw, and then cover the straw with a layer of mulch to retain moisture. Remove the plastic film and straw every 15 days to check the dryness of the sand and straw. If the sand and straw are dry, spray them with a spray bottle. Spray water finely to keep the sand moist; From late February to mid-March, take out the branches stored in sand and soak them in ABT No. 1 rooting powder at a concentration of 100 ppm for 3-4 hours, with a soaking length of 5 cm for the lower part of the branches. Seedlings are propagated by cuttings in a greenhouse. The seedbed is 1 meter wide, and 1 kg of high-quality compound fertilizer is applied per 10 meters of seedbed length as a base fertilizer. Fertilize, water the seedbed until the soil moisture is 10cm, and then cover the seedbed with a 1.5m wide black mulch film; Next, use branches to break through the black plastic mulch and insert the soaked branches in 10 cm length and width sections. Strengthen fertilizer and water management in normal times. In June, insert bamboo poles with a thickness of 2cm and a length of 1m at 50cm intervals on both sides of each seedbed. Place one pole every 5m and tie it with thin hemp rope. Pull two poles for each seedbed. Fix one thin hemp rope at 50cm from the bamboo pole. When the seedlings grow to 50cm, fix them to the thin hemp rope. S2 grafting In January of the following year, the "Golden Kiwi Rootstock No. 1" can be directly used for field planting of calyx kiwifruit, and high grafting of calyx kiwifruit can begin in mid-to-late February. First, select a grafting point with a diameter of 0.8 cm and use the cleft grafting method: The hardy kiwifruit variety is "Jinxianghong". It is best to select one-year-old hardy kiwifruit "Jinxianghong" branches as scions. The scions should be 5-7 cm long, with 2-3 buds left on each section, and the lower end should be cut into a slant. The rootstock is cut at a thickness of 0.8 cm, and then longitudinally cut, with the cut size similar to that of the scion. Then align the cambium layers of the scion and rootstock and tie them tightly with a film strip; In early to mid-June, when the 'Jinxianghong' section of the hardy kiwifruit plant awaiting grafting reaches 50 cm in length, the growing tip is pinched off to encourage the growth of 'Jinxianghong'. The new branches of the "red" tree are semi-lignified; After the grafting is successful, strengthen the management of the seedlings to allow them to grow, trellise them, establish orchards, and promptly prune the seedlings that grow from the 'Golden Kiwi Rootstock No. 1' kiwi to ensure that the grafted branches are properly trellised and put into production in a timely manner.

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