Method for evaluating yielding ability of sweet cherries

Abstract

The invention relates to the technical field of fruit tree planting, in particular to a method for evaluating the yielding ability of sweet cherries. The invention provides a method for evaluating the yielding ability of sweet cherries, which comprises the following steps: grafting to-be-evaluated sweet cherry scions to stocks, when the scions develop to an inflorescence segregation stage, counting the proportion value of the number of flower buds containing 2-4 flowers in the total number of flower buds, and judging whether the to-be-evaluated sweet cherries are in a yielding type or not according to the proportion value. According to the method provided by the invention, the yield of the new sweet cherry germplasm is rapidly identified by taking the ratio of 2-4 flowers contained in each flower bud in all flower buds in the new sweet cherry germplasm of the same age grafted on different stocks (vigorous stocks and dwarf stocks) as an evaluation index, the identification process is simplified, and the identification period is greatly shortened.

Description

Technical Field

[0001] The invention relates to the technical field of fruit tree planting, and in particular to a method for evaluating the yield of sweet cherries. Background Art

[0002] Sweet cherries are known as the "first branch of spring fruit". They are favored by consumers because of their early maturity, good benefits, and suitability for sightseeing and picking. They have also become an important economic tree species and a special tree species in various production areas, and are also known as the "fruit of wealth". So far, the national cultivation area has exceeded 3.5 million mu, ranking first in the world. The planting area has also expanded from the Bohai Bay area in the past to 25 provinces, municipalities and autonomous regions along the Longhai Railway, the high-altitude areas in the west, and the high-cold areas in the northeast.

[0003] In sweet cherry production, yield is the prerequisite for achieving ideal economic benefits. Therefore, under the same and good cultivation conditions (good irrigation and fertilization), the better the yield of the cultivated variety, the higher the yield. Therefore, cultivating high-yield sweet cherry varieties is of great significance for maintaining the stability of sweet cherry yield and improving economic benefits.

[0004] Every flower that can bear fruit is a fruit. The number of flowers directly affects the yield of fruit trees. The genetic characteristics of cultivars and rootstocks are important factors affecting the number of flowers. We investigated six sweet cherry cultivars (Shamidou, Hongdeng, Changhua Zixia, Wanmilu, Meizao) of the same age grafted on Benxi Shanying rootstock (arborized rootstock) and Gisela No. 6 rootstock (dwarfing rootstock) in Qinhuangdao. The results showed that the number of flowers in the flower buds of sweet cherry ranged from 1 to 4, and very few contained 5 flowers. At the same time, it was found that the proportion of high-yield varieties containing 2 to 4 flowers per flower bud was higher than that of non-high-yield varieties. The proportions of 2 to 4 flowers per flower bud of the six varieties on Benxi Shanying rootstock were 93%, 78%, 69%, 68% and 32%, respectively, and the proportions of 2 to 4 flowers per flower bud of the six varieties on Gisela No. 6 rootstock were 97%, 96%, 89%, 83% and 67%, respectively. The high yield of sweet cherry is mainly determined by the characteristics of the variety, and good cultivation and management measures and suitable grafted rootstocks will improve its high yield. Therefore, in the process of sweet cherry breeding, the high yield of each new cultivated variety can be judged according to the proportion of 2 to 4 flowers in each flower bud. This method simplifies the identification process and shortens the identification cycle, which is of great significance for the rapid screening of high-yield sweet cherry germplasm.

[0005] Sweet cherries have a long juvenile period and enter the fruiting period later than other stone fruit trees. To determine whether a newly bred line is high-yielding, it is necessary for it to reach the peak fruiting period. Using conventional breeding methods to breed sweet cherries, it generally takes 6 to 7 years from sowing to the peak fruiting period, which is a long time and seriously prolongs the sweet cherry breeding time. In view of this, the present invention is specially proposed. Summary of the invention

[0006] In order to solve the above technical problems, the present invention provides a method for evaluating high-yield sweet cherries, which has a short breeding cycle and can screen out germplasm with good yield in the early stage of fruiting, thereby greatly reducing the workload of breeding.

[0007] Specifically, the technical solution of the present invention is as follows: In a first aspect, the present invention provides a method for evaluating the yield of sweet cherries, comprising: grafting a sweet cherry scion to be evaluated onto a rootstock, waiting for the scion to develop to the inflorescence separation stage, counting the proportion of flower buds containing 2-4 flowers in the total number of flower buds, and judging whether the sweet cherry to be evaluated is a high-yield type based on the proportion.

[0008] Preferably, the rootstock is an arboriculture rootstock, and the judgment criteria include: if the proportion value is ≥ 65%, the sweet cherry to be evaluated is judged to be a high-yield type.

[0009] Preferably, the rootstock is a dwarfing rootstock, and the judgment criteria include: if the proportion value is ≥80%, the sweet cherry to be evaluated is judged to be a high-yield type.

[0010] Preferably, the rootstocks include tree-growing rootstocks and dwarfing rootstocks; the judgment criteria include: the number of flower buds containing 2-4 flowers grafted on the tree-growing rootstock accounts for ≥65% of the total number of flower buds, and the number of flower buds containing 2-4 flowers grafted on the dwarfing rootstock accounts for ≥80% of the total number of flower buds, then the sweet cherry to be evaluated is judged to be a high-yield type.

[0011] Preferably, the tree-forming rootstock is Benxi mountain cherry rootstock; and / or the dwarfing rootstock is Gisela No. 6.

[0012] Preferably, grafting is performed when the rootstock seedling grows to 0.6-1 cm.

[0013] Preferably, developed branches are used as scions.

[0014] Preferably, the grafting is performed by xylem budding.

[0015] Beneficial effects: The present invention provides a method for evaluating the high yield of sweet cherries, wherein a sweet cherry scion to be evaluated is grafted onto a rootstock, and when the scion develops to the inflorescence separation stage, the proportion of the number of flower buds containing 2-4 flowers in the total number of flower buds is counted, and whether the sweet cherry to be evaluated is a high-yield type is judged according to the proportion. The method provided by the present invention uses the proportion of each flower bud containing 2-4 flowers in all flower buds in new sweet cherry germplasms of the same age grafted on different rootstocks (arborized rootstocks and dwarfing rootstocks) as an evaluation index to quickly identify the high yield of new sweet cherry germplasms, and the method simplifies the identification process and greatly shortens the identification cycle. DETAILED DESCRIPTION

[0016] The present invention provides a method for evaluating the yield of sweet cherries. The method comprises the following steps: (1) preparing rootstock seedlings; (2) gathering resources; (3) shaping and pruning; and (4) measuring flower bud and flowering parameters. The method has the advantage of a short breeding cycle and can screen out germplasms with good yield at the early stage of fruiting, greatly reducing the workload of breeding.

[0017] In a more specific embodiment of the present invention, the method for evaluating high-yield sweet cherries is as follows: (1) Preparation of rootstock seedlings: Benxi cherry rootstock seedlings: In the spring of 2016, after the soil temperature at a depth of 5cm in the cold shed stabilized above 5℃, Benxi cherry seeds with the same provenance were selected for seed sowing. Point sowing was adopted, and the hole depth was 2-3cm. After sowing, the soil was scraped flat with a wooden board so that the soil covered the seeds, and then the ground was covered with film to keep moisture. After the seeds germinated and emerged from the soil, the plastic film was removed and a 50cm high arch shed was built to keep warm and moisturize. After the seedlings of the seedlings of the rootstocks became lignified, holes were punched in the plastic film of the arch shed for ventilation and began to be domesticated, and the ventilation holes and ventilation time were gradually increased. The domestication was completed in about 7 days, and the seedlings were transplanted to the field for routine water and fertilizer management. Grafting was carried out when the rootstock seedlings grew to 0.6~1cm in early September of the same year. Sowing in advance in the cold shed can lead to early emergence, and grafting can be done in the same year, which can shorten the identification cycle.

[0018] Cuttings and seedlings of Gisela No. 6 rootstock: In mid-to-late August 2015, cut healthy, disease-free, and insect-free semi-lignified new branches of the current year as cuttings. Prune the cuttings before cutting, with the lower cut being an inclined surface. The length of the cuttings is 15-20 cm, and the top leaf heart and 4-5 leaves are retained. Dip the lower end of the trimmed cuttings into a 1g / L IBA solution for 30 seconds, take them out and insert them into a sterilized substrate, with a cutting depth of 3-5 cm. Cover the cutting shed with a sunshade net, install a misting device inside to cool and moisturize, and use a humidity controller to keep the humidity at around 98% and the temperature between 25 and 28°C. Rooting can be achieved in 15 days. After rooting, reduce the humidity by 2% every 2 days. After the humidity in the cutting shed drops to 70%, stop misting, and gradually ventilate and increase light until the sunshade net is removed. After the leaves fall in winter, take out the cuttings from the substrate and bury them in a sand pit to protect them from the cold. Transplant them to the field in April of the following year and carry out routine water and fertilizer management. Grafting is carried out when the rootstock seedlings grow to 0.6~1cm in early September of the same year.

[0019] (2) Resource aggregation: In early September 2016, 11 varieties (lines) of sweet cherry, including the main varieties of production, 'Shamidou', 'Hongdeng', 'Meizao', and the superior lines '219' (approved in 2020, Changhua Zixia), '793' (approved in 2020, Wanmilu), 'Dong 8 North 17', 'Dong 6 North 29', 'Dong 6 South 11', 'Dong 8 North 1', 'Dong 6 North 26' and 'Dong 6 South 5', were selected as scions. They were grafted onto Benxi Shanying rootstock and Gisela No. 6 rootstock by xylem bud grafting, and buried in the soil 20 cm above the grafted buds in winter for cold protection. Before the buds sprouted in the spring of 2017, the stems of the rootstock seedlings were cut off 0.5-1 cm above the grafted buds. After that, the buds on the rootstocks should be wiped off in time, and conventional water, fertilizer, and pest and disease management should be carried out. After the leaves fell in November 2016, the grafted seedlings were dug out and transplanted obliquely in a 1m deep transplanting trench and covered with soil to protect against cold.

[0020] In the spring of 2017, grafted seedlings with strong growth, full branches and buds, well-developed root systems and no diseases or insect pests were selected and planted in the Science and Technology Innovation Base of Changli Fruit Research Institute of Hebei Academy of Agricultural and Forestry Sciences, and routine soil, fertilizer and water management was carried out.

[0021] (3) Shaping and pruning: The spacing of the experimental seedlings was 3m×4m, and the tree shape was slender spindle-shaped. The specific shaping and pruning method was to not set the trunk after the seedlings were planted, and to promote new branches by cutting buds and applying branching agent on the main trunk, that is, when the buds swelled, the buds within 50cm of the base of the trunk were removed, and the top bud and the two buds below were left untreated. All the remaining buds on the trunk were cut horizontally 0.5cm above the buds, deep into the wood, and branching agent was applied on the buds at the same time.

[0022] When the new branches are semi-lignified, use toothpicks or angle openers to prop up the angles to facilitate branch pulling later. You can also hang bamboo clips at the end of the branches when the branches grow to about 30 cm to make the branches close to horizontal, and move the bamboo clips forward as the branches grow. Before budding in the spring of the second year, thin out the back branches and overcrowded main branches, retain one main branch every 15 cm or so, and each main branch spirals up. The varieties (lines) grafted on Benxi Mountain Cherry control the tree height to 3.5m, with a total of about 20 main branches; the varieties (lines) grafted on Gisela No. 6 control the tree height to 3m, with a total of about 15 main branches. After thinning out the overcrowded branches, pull the branches so that each main branch is horizontal. Using this technology, the tree shape can be formed in 2 years, flower buds begin to form in the third year, a small amount of yield in the fourth year, and a high-yield period in the fifth to sixth years.

[0023] (4) Determination of flower bud and flowering parameters Among the collected germplasms, 'Shamidou', 'Hongdeng', '219' (Changhua Zixia) and '793' (Wanmilu) are high-yield varieties; 'Meizao' is a variety with poor high yield. The superior lines 'Dong8N17', 'Dong6N29', 'Dong6N11', 'Dong8N1', 'Dong6N26' and 'Dong6N5' are superior lines to be evaluated.

[0024] In 2021, the parameters of flower buds of varieties (lines) with different rootstock-scion combinations that have been planted for more than 4 years will be measured. The proportion of each flower bud containing 2 to 4 flowers in all flower buds of different varieties grafted on the same rootstock is used as the evaluation index, and the number of flowers contained in each flower bud is defined according to the known high-yield and non-high-yield varieties: sweet cherry varieties grafted on the tree-like rootstock Benxi Shanying have flower buds with a proportion of more than 65% containing 2 to 4 flowers, which is a high-yield variety; sweet cherry varieties grafted on the dwarfing rootstock Gisela 6 have flower buds with a proportion of more than 80% containing 2 to 4 flowers, which is a high-yield variety.

[0025] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be described clearly and completely below. Obviously, the described embodiments are 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.

[0026] The endpoints and any values ​​of the ranges disclosed in this specification are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

[0027] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "specific implementations", or "some specific implementations" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the embodiment of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0028] In the examples provided in this specification, if no specific techniques or conditions are specified, the techniques or conditions described in the literature in this field or the product instructions are used. If the manufacturer of the reagents or instruments used is not specified, they are all conventional products that can be purchased through regular channels.

[0029] Example 1 In the spring of 2016, the tree rootstock Benxi Mountain Cherry was prepared by seed sowing. The specific method was the same as the seed seedlings of Benxi Mountain Cherry rootstock in the preparation of the above-mentioned rootstock seedlings. In early September 2016, 11 varieties (lines) including 'Sha Mi Dou', 'Hong Deng', 'Mei Zao', '219' (Changhua Zixia), '793' (Wan Mi Lu), 'Dong 8 North 17', 'Dong 6 North 29', 'Dong 6 South 11', 'Dong 8 North 1', 'Dong 6 North 26' and 'Dong 6 South 5' were grafted on the Benxi Mountain Cherry rootstock by xylem bud grafting. The tree was shaped and pruned according to the slender spindle shape, and conventional water and fertilizer management and flower and fruit management were carried out. In 2021, the flower bud parameters of the varieties (lines) with different rootstock and scion combinations that had been planted for more than 4 years were measured. The specific determination method is to randomly determine the number of flower buds contained in each of the 100 flower buds of each variety during the inflorescence separation period, and to count the proportions of different numbers of flower buds contained in each flower bud. The determination results are shown in Table 1.

[0030] Table 1 The percentage of flowers per flower bud in varieties grafted onto Benxi mountain cherry rootstock As shown in Table 1, among the 12 varieties (lines) grafted on the Benxi cherry tree rootstock, 'Shamidou', 'Hongdeng', 'Changhua Zixia' and 'Wanmilu' are high-yield varieties, with 93%, 78%, 69% and 68% of each flower bud containing 2 to 4 flowers respectively; 'Meizao' is a low-yield variety, with 32% of each flower bud containing 2 to 4 flowers. According to the high-yield characteristics of known varieties, sweet cherry varieties on the tree rootstock with a proportion of 2 to 4 flowers per flower bud greater than 65% are judged as high-yield varieties.

[0031] Example 2 In late August 2015, the dwarf rootstock Gisela 6 was prepared by softwood cuttings. The specific cutting method was the same as the cuttings of Gisela 6 rootstock in the preparation of the above rootstock seedlings. In early September 2016, 11 varieties (lines) including 'Shamidou', 'Hongdeng', 'Meizao', '219' (Changhua Zixia), '793' (Wanmilu), 'Dong8N17', 'Dong6N29', 'Dong6N11', 'Dong8N1', 'Dong6N26' and 'Dong6N5' were grafted on Gisela 6 rootstock by xylem bud grafting. The trees were shaped and pruned according to the slender spindle shape, and conventional water and fertilizer management and flower and fruit management were carried out. In 2021, the flower bud parameters of the varieties (lines) with different rootstock and scion combinations that had been planted for more than 4 years were measured. The specific determination method is to randomly determine the number of flower buds contained in each of the 100 flower buds of each variety during the inflorescence separation period, and to count the proportions of different numbers of flower buds contained in each flower bud. The determination results are shown in Table 2.

[0032] Table 2 The percentage of flowers per bud in varieties grafted on Gisela 6 rootstock As shown in Table 2, among the 12 varieties (lines) grafted on the dwarf rootstock Gisela 6, 'Shamidou', 'Hongdeng', 'Changhua Zixia' and 'Wanmilu' are high-yield varieties, with 97%, 89%, 83% and 96% of each flower bud containing 2 to 4 flowers respectively; 'Meizao' is a low-yield variety, with 67% of each flower bud containing 2 to 4 flowers. Based on the high-yield characteristics of known varieties, sweet cherry varieties on dwarf rootstocks with a proportion of 2 to 4 flowers per flower bud greater than 80% are judged as high-yield varieties.

[0033] Example 3 Based on the schemes provided in Example 1 and Example 2, under the same pruning mode and management mode: the proportion of 2 to 4 flowers in each flower bud of the sweet cherry germplasm grafted on the tree-like rootstock Benxi Mountain Cherry is higher than 65%, which is determined to be a high-yield variety; the proportion of 2 to 4 flowers in each flower bud of the sweet cherry germplasm grafted on the dwarfing rootstock Gisela No. 6 is higher than 80%, which is determined to be a high-yield variety. According to this standard, the high-yield varieties (lines) are 'Shamidou', 'Hongdeng', '219' (Changhua Zixia), '793' (Wanmilu), 'Dong 8 North 17', 'Dong 6 North 29', 'Dong 6 South 11' and 'Dong 8 North 1', and the non-high-yield varieties (lines) are 'Meizao', 'Dong 6 North 26' and 'Dong 6 South 5'.

[0034] To verify the feasibility of the screening method of the present invention, the yield of 11 varieties (lines) grafted on two rootstocks and planted for 6 years were measured in 2023. Three plants were selected from each rootstock-scion combination, and the average value was measured. The measurement results are shown in Table 3.

[0035] Table 3 Yield of 6-year-old trees of various varieties grafted on two rootstocks After yield measurement and comparison, it was verified that the screening methods provided in Example 1 and Example 2 are feasible, that is, the proportion of sweet cherry varieties (lines) grafted on the tree-like rootstock Benxi Mountain Cherry containing 2 to 4 flowers in each flower bud exceeds 65%, and the proportion of sweet cherry varieties (lines) grafted on the dwarfing rootstock Gisela No. 6 containing 2 to 4 flowers in each flower bud exceeds 80%, which can be determined as high-yield varieties.

[0036] In summary, the present invention provides a method for evaluating high-yield sweet cherries. The method is simple, effective, and has a short cycle, and can shorten the breeding cycle for screening high-yield varieties.

[0037] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for evaluating the yield of sweet cherries, characterized in that: The sweet cherry scion to be evaluated is grafted onto the rootstock. When the scion develops to the inflorescence separation stage, the proportion of the number of flower buds containing 2-4 flowers in the total number of flower buds is counted, and whether the sweet cherry to be evaluated is a high-yield type is determined based on the proportion.

2. The method for evaluating sweet cherry yield according to claim 1, characterized in that: The rootstock is an arborescent rootstock, and the judgment criteria include: if the proportion value is ≥65%, the sweet cherry to be evaluated is judged to be a high-yield type.

3. The method for evaluating sweet cherry yield according to claim 1, characterized in that: The rootstock is a dwarfing rootstock, and the judgment criteria include: if the proportion value is ≥80%, the sweet cherry to be evaluated is judged to be a high-yield type.

4. The method for evaluating sweet cherry yield according to claim 1, characterized in that: The rootstocks include tree-growing rootstocks and dwarfing rootstocks; the judgment criteria include: if the number of flower buds with 2-4 flowers grafted on the tree-growing rootstock accounts for ≥65% of the total number of flower buds, and the number of flower buds with 2-4 flowers grafted on the dwarfing rootstock accounts for ≥80% of the total number of flower buds, then the sweet cherry to be evaluated is judged to be a high-yield type.

5. The method for evaluating sweet cherry yield according to any one of claims 1 to 4, characterized in that: The tree-forming rootstock is Benxi Prunus armeniaca rootstock; and / or the dwarfing rootstock is Gisela No.

6.

6. The method for evaluating sweet cherry yield according to any one of claims 1 to 5, characterized in that: Grafting is carried out when the rootstock seedlings grow to 0.6-1cm.

7. The method for evaluating sweet cherry yield according to any one of claims 1 to 6, characterized in that: Use developed branches as scion.

8. The method for evaluating sweet cherry yield according to any one of claims 1 to 7, characterized in that: Grafting is done by xylem budding.

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