Strawberry cultivation method, strawberry seedling production method, strawberry seedling, and cultivation container

Abstract

To control the direction of fruit cluster formation in strawberry production. [Solution] The present invention relates to a method for cultivating strawberries, which includes the step of planting seedlings in a direction defined based on the elongation direction of the primary runners.

Description

Technical Field

[0001] The present invention relates to a method for cultivating strawberries, a method for producing strawberry seedlings, strawberry seedlings, and a cultivation container.

Background Art

[0002] In strawberry production in Japan, the main method of propagating seedlings is vegetative propagation by runners. Specifically, more than half a year before harvesting strawberry fruits, first, mother plants are raised and planted in pots. Then, runners grow from spring to summer. For example, the tip of a runner is received and fixed in a pot filled with culture soil, and after the roots are established, the runner is cut to form and propagate daughter plants. When many daughter plants are formed from one mother plant by runners, dozens of daughter plants can be formed. These daughter plants are raised from summer to autumn and then planted in the main field in a forcing house around September, and fruits are harvested from November to around May of the following year. The above is the procedure for strawberry production by general house forcing cultivation in Japan.

[0003] While vegetative propagation via runners offers advantages such as the easy acquisition of uniform plants, it also carries the risk of significant damage if the parent plant is infected with pests, diseases, or viruses, as these can be transmitted to the offspring. To mitigate this risk, seed-propagated varieties have recently been developed and are attracting attention in strawberry production. Specifically, seed-propagated strawberry varieties are F1 varieties created by crossing self-pollinated, stable parent varieties, and seedling propagation is carried out by sowing seeds obtained from the cross of the parent varieties. When producing strawberries using seed-propagated varieties, strawberry producers purchase seeds or seedlings from seedling suppliers, grow them, and then, similar to vegetative propagation, plant them in the main field within a greenhouse for forcing cultivation and harvest fruit until the following spring. Seed-propagated varieties have superior cost-effectiveness, as they eliminate the need for preparing parent plants and receiving runners as in vegetative propagation. Furthermore, the risk of parent-offspring transmission of pests, diseases, and viruses is expected to be significantly reduced compared to vegetative propagation. Therefore, seed-propagated varieties are seen as effective in establishing new production systems for strawberries, particularly for their use in organic strawberry cultivation, and further research into their cultivation methods is desired.

[0004] In strawberry production, it is desirable for the direction in which fruit clusters (flower clusters) form to be aligned with the outside of the planted ridges or elevated benches. For example, in soil cultivation, it is important from the standpoint of efficiency in fruit harvesting and from the standpoint of preventing diseased fruit for plants planted on elevated ridges in the main field to have fruits uniformly formed on the aisle side. In this regard, it has been known for some time that in the case of vegetative propagation, fruit clusters form on the opposite side of the point where the runner connecting to the parent plant is cut off in the seedling. That is, in vegetative propagation, if the runner point is facing inward towards the ridges or elevated benches at the time of planting, fruit clusters will form on the aisle side. Furthermore, Non-Patent Literature 1 discusses the relationship between the direction of crown inclination and the direction of flower cluster elongation, and shows that when planting cultured seedlings that do not have a runner axis (the point where the runner from the parent plant is cut) and crown inclination, it is possible to make the flower clusters elongate towards the aisle by tilting the plants towards the aisle at the time of planting. [Prior art documents] [Non-patent literature]

[0005] [Non-Patent Document 1] Research on the development of year-round production technology and the breeding and dissemination of year-round cultivated varieties through elucidation of the physiological and ecological characteristics of strawberries, Yukio Inaba, Tochigi Prefectural Agricultural Experiment Station Research Report, No. 61, pp. 1-66, March 2008. [Overview of the project] [Problems that the invention aims to solve]

[0006] As mentioned above, in vegetative propagation, the runner marks from the parent plant serve as indicators of the direction of fruit cluster (flower cluster) formation. On the other hand, in the cultivation of seed-propagated varieties, since there is no parent plant, the aforementioned runner marks from the parent plant that could serve as indicators are not formed. Therefore, in order to align the direction of fruit cluster formation in the cultivation of seed-propagated varieties, different indicators or measures are required than in the case of vegetative propagation. Referring to Non-Patent Document 1, a method of planting seedlings at a large angle towards the aisle can be considered, but in soil cultivation, planting at an angle causes the fruit formation area to descend to a position close to the aisle surface, which can actually hinder harvesting. Furthermore, there is also the problem that damage and dirt can occur on the fruit surface due to contact with the ground and unintentional contact with harvesters, which can easily lead to a decrease in commercial value.

[0007] One aspect of the present invention has been made in view of the above-mentioned problems, and aims to realize a method for controlling the direction of fruit cluster formation in strawberry production. [Means for solving the problem]

[0008] After extensive research, the inventors discovered that the direction of elongation of the first runners (primary runners) formed during seedling cultivation is related to the direction of fruit cluster (flower cluster) formation.

[0009] In other words, in order to solve the above problems, one aspect of the present invention provides a method for cultivating strawberries, which includes the step of planting seedlings in a direction defined based on the direction of elongation of the primary runners.

[0010] Another aspect of the present invention provides a method for producing strawberry seedlings, the method comprising the step of marking them to indicate the direction of planting.

[0011] Furthermore, another aspect of the present invention provides a strawberry seedling with markings indicating the direction of planting.

[0012] Furthermore, another aspect of the present invention provides a cultivation container in which a plurality of strawberry seedlings are planted in a orientation defined based on the elongation direction of the primary runners. [Effects of the Invention]

[0013] According to one aspect of the present invention, the direction of fruit cluster formation in strawberry production can be controlled. [Brief explanation of the drawing]

[0014] [Figure 1] This diagram illustrates an example of planting strawberry seedlings in a orientation determined based on the direction of elongation of their primary runners. [Figure 2] This is yet another diagram illustrating an example of planting strawberry seedlings in a orientation determined based on the direction of elongation of their primary runners. [Figure 3] This figure shows the relationship between the elongation direction of the primary runner of a strawberry plant and the direction of fruit cluster formation according to Embodiment 1 of the present invention. [Figure 4] This figure shows an example of the position of the center of a fruit cluster according to Embodiment 1 of the present invention. [Modes for carrying out the invention]

[0015] [Definition] In this specification, "strawberry" broadly refers to cultivated varieties belonging to the genus Fragaria (Fragaria L.) that are grown for the purpose of harvesting fruit, and typically refers to the plant with the scientific name Fragaria × ananassa of the genus Fragaria in the family Rosaceae.

[0016] In this specification, "fruit" refers to the pseudocarp formed when the receptacle of a strawberry swells. "Fruit cluster" refers to the part of the strawberry where the fruit grows in clusters, specifically the part where multiple fruits are formed at the end of the fruit stalk that emerges from the crown. In other words, the number of "fruit clusters" is equal to the number of fruit stalks.

[0017] The strawberry varieties covered in this specification may be everbearing varieties that bear fruit throughout the four seasons, or single-season varieties that bear fruit once a year. Furthermore, the strawberry varieties covered in this specification may be varieties that are propagated by conventional vegetative propagation (hereinafter also referred to as "conventional varieties"), but seed-propagated varieties are preferred. Here, "seed-propagated varieties" means F1 varieties obtained by crossing self-pollinated fixed lines as parent varieties, as described above. In seed-propagated varieties, seedlings can be propagated by sowing seeds obtained by crossing the parent varieties. Examples of seed-propagated varieties include, for example, "Yotsuboshi (Japanese Variety Registration No. 25605)", "Chiba F-1 (Japanese Variety Registration No. 20844)", "Berry Pop Haruhi (Japanese Variety Registration Application Pending, Application Name: MYAGFRA-1)", and "Berry Pop Suzu (Japanese Variety Registration Application Pending, Application Name: MYAGMIE-1)".

[0018] In this specification, unless otherwise specified, "seedling" refers to a young strawberry plant before it is transplanted into the main field. Among these, plants grown from seeds are also referred to as "seedlings" in this specification.

[0019] In this specification, the term "runner" refers to the runner (stolon) that grows and extends from the leaf axils of the short stems (crowns) at the edge of the strawberry nursery. Runners occur not only in conventional varieties but also in seedlings of seed-propagated varieties. Runners that develop from strawberry seedlings for fruit harvesting can have buds at their tips, but are usually cut off at the seedling raising stage.

[0020] In this specification, among the "runners", the runner that first grows and extends from the seedling is specifically referred to as the "primary runner".

[0021] In this specification, "planting" refers to transplanting the seedling to the place where it will ultimately be grown (hereinafter also referred to as the "main field"). The planted strawberry seedlings are continuously cultivated in the main field until they form fruits thereafter.

[0022] In this specification, when indicating a range in the form of "A to B", this notation is used in the sense of including both A and B at the two ends of the range, unless otherwise specified.

[0023] [1. Method for Cultivating Strawberries] The method according to one embodiment of the present invention is a method for cultivating strawberries, including the step of planting a seedling in a direction defined based on the extending direction of the primary runner. An example of this method is a method for cultivating strawberries, including the step of aligning the primary runner or the cutting mark of the primary runner in a predetermined direction and planting the seedling. In the description of this section, the description focuses on the embodiments related to the period before and after planting the strawberry seedling, and the growth period from sowing until the seedling grows to a certain extent will be described in detail in the later section [2. Method for Producing Strawberry Seedlings].

[0024] That is, in the method according to one embodiment of the present invention, the timing of planting the seedling is after the primary runner has developed from the seedling. When planting, the primary runner may or may not be cut, but in order to avoid unnecessary nutrient consumption of the plant body, it is preferable to cut the primary runner at the latest after planting.

[0025] An example of planting strawberry seedlings in a orientation determined based on the direction of elongation of their primary runners will be explained using Figures 1 and 2. Figure 1 is a diagram illustrating the direction of elongation of the primary runners of a strawberry seedling viewed from directly above. Figure 1 shows only the base (the part of the crown at the base from which the petiole emerges) and the runners of the strawberry seedling. The base 11 is roughly shown as a circle, and the runners 13 extending from the base 11 are shown as dotted lines. For illustrative purposes, Figure 1 shows three hypothetical runners 13 that originate from the same part 130 of the base 11. These three runners 13, after originating from the same part 130 of the base 11, grow almost straight in the same direction, and then curve and grow in different directions as they move away from the base 11. In this specification, the extension direction of the (primary) runner refers to the direction indicated by the straight arrow drawn from the center 110 of the base 11 through the runner generation site 130 (illustrated as the extension direction 12), meaning that the extension direction of these three runners 13 is the same extension direction 12.

[0026] The orientation in which strawberry seedlings are planted is determined based on the direction of elongation of their primary runners. Specifically, when viewing the strawberry seedling from directly above, it is planted so that the direction of elongation of the primary runners faces the predetermined direction. One example of the orientation in which strawberry seedlings are planted is so that the opposite side of the primary runner's elongation direction is positioned relative to the access space for the strawberries. In this case, even if the primary runner is extended, it will not reach the access space corresponding to the seedling. The access space for strawberries refers to the space where people or robots enter to harvest the fruit, and specifically refers to, for example, a passageway.

[0027] The definition of "opposite side with respect to the direction of growth of the primary runner" mentioned above will be explained in detail below with an example. For example, when growing strawberries in elevated cultivation, as shown in Figure 1, the space 32 for accessing the strawberries may be defined by the end 310 of the longitudinal cultivation container 31 for elevated cultivation. Here, the opposite side with respect to the direction of growth of the primary runner is the area shown as "A: Opposite side" in Figure 1. The area shown as "A: Opposite side" is the area on the side that does not include the runner 13 (i.e., the side that does not include the arrow of the growth direction 12) when a virtual line 21 is drawn in the plane including the direction of growth of the primary runner, passing through the base 11 and parallel to the end 310 of the strawberry cultivation container 31. Note that when the virtual line 21 is drawn, the area on the side that includes the runner 13 is shown as "B: Same side". As will be described later, the area indicated as "A: opposite side" is an area where there is a very high probability that the fruit stalk (flower stalk) will grow from the base 11 side. Therefore, planting strawberry seedlings in this direction will make fruit harvesting easier. Note that the strawberry plant is facing the same direction at the stage after planting and at the stage of fruit harvesting. One example of the direction in which to plant strawberry seedlings as described above can also be rephrased as the direction in which the smaller of the angle between a straight arrow (illustrated as a virtual direction 22) drawn perpendicularly from the center 110 of the base 11 to the end 310 of the strawberry cultivation container 31 and the elongation direction 12 of the primary runner is greater than 90° and less than or equal to 180°.

[0028] Based on Figure 2, we will explain in more detail an example of the orientation in which strawberry seedlings are planted. Figure 2 is a diagram showing multiple strawberry seedlings planted in a long cultivation container 31 used for elevated cultivation, etc., as viewed from directly above. Only the base 11 and the direction of elongation 12 of the primary runner are shown for the strawberry seedlings. On both sides of the cultivation container 31, aisles S11 and S12 are provided along the longitudinal direction of the cultivation container 31. The strawberry seedlings are planted in two rows (for example, in a staggered arrangement of two rows). In the row of seedlings on the aisle S11 side, the opposite side of the primary runner elongation direction 12 is planted so as to face aisle S11. In the row of seedlings on the aisle S12 side, the opposite side of the primary runner elongation direction 12 is planted so as to face aisle S12. In each row of strawberry seedlings, the direction of elongation 12 of the primary runners is not exactly the same for all seedlings. Using the most ideal state shown in Figure 1 (i.e., A: the opposite side faces the aisle) as a reference, the direction of elongation 12 of the primary runners can be shifted by, for example, up to 45° to the left and right, up to 40° to the left and right, up to 35° to the left and right, up to 30° to the left and right, up to 25° to the left and right, up to 20° to the left and right, up to 15° to the left and right, or up to 10° to the left and right, around the base 11.

[0029] As mentioned above, the orientation for planting in elevated cultivation is important. However, in other cases, such as when growing strawberries in open fields or soil, the space available for accessing the strawberries can be determined by the ends of the planting rows. In other words, in the case of open fields or soil, you can determine the orientation for planting the strawberry seedlings by replacing "long cultivation containers for elevated cultivation" with "rows" in the example of elevated cultivation described above.

[0030] The number of strawberry seedlings to be planted is determined appropriately according to the area of ​​the planting location (cultivation facility such as a greenhouse or field). There is no particular limit to the number of seedlings, but for example, it could be 10 or more, 20 or more, 30 or more, 40 or more, 50 or more, 100 or more, 300 or more, 500 or more, or 1000 or more. There is also no particular limit to the number of seedlings, and it is only subject to the area of ​​the planting location, but for example, it could be 1 million or less, 100,000 or less, 50,000 or less, 10,000 or less, or 5000 or less. When multiple strawberry seedlings are planted in the same cultivation facility or field, for example, 60% or more, 70% or more, 80% or more, 90% or more, 90% or more, 95% or more, 96% or more, 97% or more, 98% or more, of the plants are planted in a orientation determined based on the direction of elongation of their primary runners (for example, so that the opposite side of the primary runner's elongation direction faces the space for accessing the strawberry).

[0031] Although primary runners usually develop before flower bud differentiation, it is preferable to wait until flower bud differentiation has occurred before transplanting. Transplanting before flower bud differentiation can lead to excessive vegetative growth, increasing the risk of delayed fruit setting and the occurrence of malformed fruits. In other words, it is desirable to transplant seedlings only after both the development of primary runners and flower bud differentiation have been confirmed. Confirmation of flower bud differentiation can be done using methods well known to those skilled in the art, such as flower bud microscopy, which involves peeling off the undeveloped leaves at the top of the crown and observing the inside under a microscope.

[0032] In addition, to ensure healthy growth and yield after transplanting, it is preferable to transplant seedlings that have grown to a crown diameter of 8 mm or more, and even more preferable to transplant seedlings that have grown to a crown diameter of 10 mm or more.

[0033] A method according to one embodiment of the present invention may further include a step of marking the seedlings with an indicator of the direction of elongation of the primary runners before the step of planting the seedlings. By applying such markings, it becomes easier to determine the direction in which the seedlings should be aligned at the time of planting.

[0034] The method of marking the direction of primary runner elongation is not particularly limited, as long as it allows for easy identification of the orientation of the seedling when planting. Specifically, possible methods include: 1) marking using the seedling's tissue itself (for example, cutting the elongated primary runner in a way that makes it distinguishable from other tissues), 2) directly marking the seedling (for example, wrapping vinyl tape around the elongated primary runner), 3) marking a part of the seedling other than the plant body (for example, in a pot containing the seedling, attaching vinyl tape to the edge of the pot in the direction of primary runner elongation from the plant body, or inserting a label into the potting soil in the pot containing the seedling at a position in the direction of primary runner elongation from the plant body), or 4) a combination of these methods. The number of markings is not particularly limited and can be appropriately selected depending on the marking method; for example, it could be one, two, or three or more.

[0035] Primary runners may fall off due to aging in the later stages of seedling growth, and therefore, if markings are attached to the plant body, there is a risk of the markings being lost. For this reason, the method of attaching markings is preferably either the method described in 3) above, which involves attaching the markings to a part of the seedling other than the plant body, or a combination of method 3) and method 1) or 2) above. On the other hand, primary runners may develop before the seedling has taken root in the potting soil, and in that state, markings attached to a part of the plant other than the plant body may not accurately indicate the direction of runner elongation. For this reason, the method described in 3) above, which involves attaching the markings to a part of the seedling other than the plant body, is more preferably a step of attaching the markings to a part of the plant other than the plant body after confirming that the seedling has taken root sufficiently in the potting soil and that there is no more wobbling at the base of the plant, or a step of adjusting the position of the markings.

[0036] Strawberries continue to produce multiple runners as they grow, both after the primary runner emerges and after transplanting. These runners, i.e., secondary runners and beyond, may or may not be cut, but to avoid unnecessary nutrient consumption by the plant, it is preferable to cut all secondary runners and beyond as soon as their emergence is confirmed. Furthermore, to avoid confusion between primary and secondary runners, it is preferable to perform the marking described above before secondary runners emerge. In addition, the marking method using the seedling tissue itself as described in 1) above may involve cutting the primary runner in a way that distinguishes it from secondary runners and beyond. For example, the method of cutting the primary runner and secondary runners and beyond can be varied to make the cut mark of the primary runner (the trimmed primary runner) visible. One example of varying the cutting method between primary and secondary runners and beyond is to leave a longer cut mark only on the primary runner, while cutting secondary runners and beyond near the base.

[0037] The inclination of strawberry seedlings relative to the soil surface at the time of planting is not particularly limited; they may be perpendicular to the soil surface or inclined towards the access path. Specifically, in soil cultivation, the angle between the planting direction of the strawberry seedling and the soil surface may be in the range of 45° to 90°, for example, but it is preferable that it be in the range of 70° to 90°, considering the risk of the fruit formed by the elongated fruit stalk touching the ground.

[0038] The cultivation method after transplanting is not particularly limited; for example, it may be open-field cultivation or greenhouse cultivation. However, greenhouse cultivation is preferable when using varieties suitable for forced cultivation. Greenhouse cultivation mainly involves greenhouse cultivation using a greenhouse covered with covering material under the open sun. Cultivation methods using closed facilities such as plant factories may also be adopted. In this case, the temperature, humidity, light-dark cycle, nutrient supply, carbon dioxide supply, and water supply should be appropriately set to be automatically managed according to the strawberry variety being cultivated. In any cultivation method, it is preferable to perform a soil analysis before transplanting and determine the amount of basal fertilizer to be applied.

[0039] Greenhouse cultivation includes soil cultivation and elevated cultivation. Soil cultivation is a method in which the ground is tilled, ridges are made to form the main field, and seedlings are planted. Elevated cultivation is a method in which elevated benches are assembled from steel materials, and strawberry cultivation containers are placed at a position where management work on the benches is easy to perform to form the main field, and seedlings are planted. The method should be selected to suit each strawberry variety, but for example, in soil cultivation, a method can be adopted in which seedlings are planted in a staggered pattern in two rows with a spacing of about 20 cm between plants on semi-circular ridges. The height of the ridges should be appropriately selected depending on the variety and soil conditions, taking into consideration ease of work, the risk of fruit touching the ground, and the risk of waterlogging, for example, they can be formed at a height of 15 cm to 30 cm, preferably about 30 cm. Similarly, in the case of elevated cultivation, a method can be adopted in which seedlings are planted in a staggered pattern in two rows with a spacing of about 20 cm between plants in cultivation containers filled with growing soil on elevated benches.

[0040] The following is an example of a cultivation schedule for this embodiment, assuming forced cultivation in a greenhouse. Seedling production (seedling raising) is carried out from April to September, from sowing to before transplanting, as described later. After flower bud differentiation and primary runner elongation are confirmed, markings are made using the direction of primary runner elongation as an indicator, and the seedlings are planted aligned in the predetermined direction using these markings as an indicator, and then the primary runners are cut from the base of the plant. After transplanting, if temperature, humidity, and light / darkness are appropriately managed according to the variety and soil environment, as well as the supply of nutrients, carbon dioxide, and water, harvesting will be possible from around November to around May of the following year, with the direction of fruit cluster formation aligned in the opposite direction to the direction of primary runner elongation. Here, the condition where the direction of fruit cluster formation is "opposite to the direction of primary runner elongation" refers to a state where, for example, when viewing a strawberry plant from above, the smaller of the angles formed between the line segment connecting the fruit cluster and the planting position of the strawberry plant and the direction of primary runner elongation is greater than 90° and less than or equal to 180°. This angle can also be considered as the smaller of the angles formed between the direction of fruit stalk (flower stalk) elongation (similar to the direction of primary runner elongation, the direction in which the fruit stalk extends from the base 11 shown in Figure 1) and the direction of primary runner elongation. Alternatively, this angle may be considered as the smaller of the angles formed between the center of the fruit cluster (the part that is the center of gravity of the multiple fruits in the fruit cluster when viewed from above) and the direction of primary runner elongation, as shown in the example described later. Depending on the variety and seedling cultivation method, long-day treatment may be performed before and after transplanting to enable early harvesting, and long-day treatment may also be performed at an appropriate time after transplanting to maintain plant vigor.

[0041] As described above, the inventors have found that in strawberry seedlings, fruit clusters are formed on the opposite side of the direction of primary runner development. In other words, by employing the method according to the above embodiment, the direction of strawberry fruit cluster formation is aligned to a predetermined direction, thereby making it possible to control the direction of strawberry fruit cluster formation.

[0042] [2. Method for producing seedlings] A method according to one embodiment of the present invention is a method for producing strawberry seedlings, which includes the step of marking the seedlings to indicate the direction of planting.

[0043] The process of producing strawberry seedlings, or in other words, seedling cultivation, is thought to include, for example, a primary seedling cultivation process in which seeds obtained by crossbreeding a predetermined self-pollinated and fixed line are sown, and the seeds are germinated and grown to a certain size; and a secondary seedling cultivation process in which the seedlings after the primary cultivation are transplanted and grown further until they can be planted in the ground. When forced cultivation is carried out in a greenhouse, the primary and secondary seedling cultivation processes are usually carried out from around April to September.

[0044] In primary seedling cultivation, the sowing method is not particularly limited, but for example, a method of filling cell trays or seedling boxes with seedling growing medium and sowing seeds can be employed. After sowing, temperature, water supply, light irradiation, etc. should be controlled as appropriate until germination. After germination, seedlings can be grown in the same cell trays or seedling boxes where they were sown, and temperature, water supply, fertilizer supply, light irradiation, etc. should be controlled as appropriate until the start of secondary seedling cultivation. If seeds are sown in seedling boxes (broadcast sowing), after germination, they may be transplanted into cell trays and seedling cultivation may be continued until the start of secondary seedling cultivation.

[0045] In secondary seedling cultivation, the primary seedlings are usually continued until they reach a certain size. Then, each seedling is transplanted into an appropriate cultivation container such as a plastic pot, depending on its size, and its growth is continued until planting. The cultivation method used in secondary seedling cultivation can be selected according to the variety, and specifically, this includes continuing cultivation in a rain-shelter greenhouse with covering material only on the top. In secondary seedling cultivation, temperature, water supply, fertilizer supply, and light irradiation are appropriately controlled according to the variety to promote flower bud differentiation.

[0046] In forced cultivation using single-fruiting varieties, nitrogen supply should be restricted as appropriate to induce flower bud differentiation. Furthermore, to increase early yields in forced cultivation, night cooling treatment may be performed during the secondary seedling stage. Specifically, for example, during the secondary seedling stage (which is expected to be mid-to-late August in forced cultivation), seedlings should be moved to a dark, low-temperature environment of approximately 12-15°C for 8-12 hours from evening to the following morning. This treatment may involve moving the seedlings to a refrigerator for night cooling treatment.

[0047] Around the time of the start of flower bud differentiation, runners emerge from seedlings during secondary nursery cultivation. Therefore, the step of marking to indicate the direction of planting is included in the secondary nursery cultivation process, and may be, for example, a step of marking using the direction of elongation of the first runner (primary runner) that emerged during secondary nursery cultivation as an indicator. The secondary nursery cultivation process may further include a step of cutting the primary runner, leaving a longer cut mark, after the marking step. The step of marking using the direction of elongation of the primary runner as an indicator is as explained in section [1. Strawberry Cultivation Method].

[0048] The method according to this embodiment makes it possible to produce strawberry seedlings that have indicators for aligning the direction of fruit cluster formation.

[0049] [3. Strawberry seedlings] A strawberry seedling according to one embodiment of the present invention is provided with a marking indicating the direction of planting.

[0050] As explained in section [1. Strawberry Cultivation Methods], methods for marking strawberry seedlings include marking using the seedling's tissue itself, marking directly on the seedling, marking on a part of the seedling other than the plant body, or a combination of these. In other words, "with marking" can mean having markings using the seedling's tissue itself, marking directly on the seedling, or marking on a part of the seedling other than the plant body.

[0051] Furthermore, even in cultivation by vegetative propagation, seedlings usually have a mark where the runner from the parent plant was cut. However, the runner mark on seedlings propagated by vegetative propagation is in contact with the rooting site at the base of the crown, making it possible to distinguish them from seedlings that have a cut mark from a runner that extended from the leaf axil of the crown.

[0052] The strawberry seedlings according to this embodiment include, for example, those produced by the method described in section [2. Method for producing seedlings]. The method for providing the strawberry seedlings according to this embodiment is not particularly limited, but they may be provided, for example, planted in a plastic pot filled with potting soil.

[0053] Businesses selling strawberry seedlings may prepare various product description materials such as catalogs, leaflets, and labels that describe (including electronic records) the relationship between the planting direction, the direction of fruit cluster formation, and the markings. Businesses selling strawberry seedlings may also prepare various product description materials such as catalogs, leaflets, and labels that describe (including electronic records) how to cultivate strawberries using these seedlings. The matters to be described in the product description materials are those described in section [1. Strawberry Cultivation Method], in particular, matters concerning the relationship between the direction in which strawberry seedlings are planted and the direction of elongation of their primary runners.

[0054] [4. Cultivation containers and cultivation equipment] A cultivation container according to one embodiment of the present invention is configured in which strawberry seedlings are planted aligned in a predetermined direction. In one example of a cultivation container, multiple strawberry seedlings are planted in a direction defined based on the direction of elongation of the primary runners. Furthermore, a cultivation device according to one embodiment of the present invention comprises a cultivation container in which strawberry seedlings are planted in a predetermined direction. The method for planting the strawberry seedlings is as described in the section [1. Strawberry Cultivation Method], and the cultivation container 31 shown in Figure 2 corresponds to a cultivation container according to one embodiment of the present invention.

[0055] An example of a cultivation apparatus may include a configuration that includes a bench used for elevated cultivation, as described in section [1. Strawberry Cultivation Method]. That is, a cultivation apparatus according to one embodiment of the present invention includes, for example, a steel elevated bench for elevated cultivation. The elevated bench has a height that facilitates management work, that is, a height that allows workers to work on the strawberry plants planted on the elevated bench while standing upright.

[0056] On the elevated bench, there are cultivation containers filled with a growing medium such as peat moss, and irrigation pipes, etc. Seedlings that have grown to a suitable size are planted in the cultivation containers, aligned in a predetermined direction. Here, the predetermined direction is, for example, the direction indicated by the markings on the seedlings when planting seedlings as described in section [3. Strawberry Seedlings]. Cultivation containers are usually arranged along the long side at both ends of the elevated bench, but by planting the seedlings aligned in the predetermined direction, for example, the fruit clusters can be formed aligned on the outside of both ends of the elevated bench, i.e., on the side of the walkway where workers pass. Note that the cultivation containers may also be those for hydroponics.

[0057] The cultivation apparatus according to this embodiment is expected to improve the harvesting efficiency of strawberries and avoid the occurrence of diseased fruit, even when using seedlings grown from seed in elevated cultivation.

[0058] [summary] In summary, the present invention can also be summarized as follows, based on the embodiments described above. (1) A method for cultivating strawberries, comprising the step of planting seedlings in a direction specified based on the direction of elongation of the primary runners. (2) The method according to (1), further comprising the step of marking the primary runners with an indicator of their elongation direction before planting the seedlings. (3) The method according to (1) or (2), wherein the primary runner is planted such that the opposite end of the runner, relative to the direction of elongation, is positioned relative to the space for accessing the strawberry. (4) The strawberry is a seed-propagated variety, according to any of the methods in (1) to (3). (5) A method for producing strawberry seedlings, comprising the step of marking a planting direction. (6) Strawberry seedlings with markings indicating the direction of planting. (7) The markings are defined based on the direction of elongation of the primary runner, as described in (6). (8) A cultivation container in which multiple strawberry seedlings are planted in orientations determined based on the direction of elongation of the primary runners. And a strawberry cultivation apparatus comprising the said cultivation container.

[0059] The present invention is not limited to the embodiments described above, and various modifications are possible within the scope of the claims. Embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included in the technical scope of the present invention. [Examples]

[0060] An embodiment of the present invention will be described below, but the scope of the present invention is not limited to this embodiment. In the following embodiment, the strawberry seed-propagated variety "Yotsuboshi" (a variety jointly developed by Mie Prefecture, Kagawa Prefecture, Chiba Prefecture, and the National Agriculture and Food Research Organization) was used in all tests.

[0061] (Example 1: Test using planter planting) "Yotsuboshi" seeds were sown in 200-cell seed trays, and after germination, the seedlings were allowed to continue growing in the seed trays for the first stage of seedling cultivation. 42 days after sowing, all seedlings were transplanted into 9cm diameter plastic pots filled with potting soil (organic horticultural soil) for the second stage of seedling cultivation. Approximately 70 days after sowing, primary runners were observed in each seedling. To mark these runners, when viewed from above, labels were inserted into the rim of the pot in the direction from which the primary runner had grown, relative to the center of the seedling. After marking, the primary runners were cut, leaving approximately 5cm from the base, and seedling cultivation continued. After the base of the seedlings had stabilized, the position marked with a label was made to finalize the direction of primary runner elongation. 158 days after sowing, a total of 30 marked seedlings were transplanted into 10 planters measuring 64cm x 22cm filled with potting soil (organic horticultural soil), with 3 seedlings in each planter. Cultivation continued until fruit formation. When transplanting, the direction marked during seedling cultivation was used as a guide, and all seedlings were transplanted in the same direction into the planters. Furthermore, all seedlings were transplanted perpendicular to the soil surface. After confirming that all seedlings were transplanted in the designated direction, the labels were removed from each seedling. 155 days after transplanting, after multiple fruit clusters had been confirmed in all seedlings, the relationship between the direction of primary runner elongation (i.e., the direction marked during seedling cultivation) and the direction of fruit cluster formation was investigated for each seedling.

[0062] Figure 3 shows one of the survey results. Figure 3 is a diagram showing the relationship between the elongation direction of the primary runner of a strawberry plant and the direction of fruit cluster formation in this embodiment. Specifically, the survey involved viewing each plant in the planter from above, defining the area in the elongation direction of the primary runner (hereinafter also referred to as the "elongation direction area") and the area in the opposite direction (hereinafter also referred to as the "opposite direction area") based on the planting position of the plant, and then confirming which area the fruit cluster was formed in for each plant. Here, based on the planting position of the plant, if the smaller of the angle between the line segment connecting the center of the fruit cluster and the planting position of the plant and the elongation direction of the primary runner was 0° or more and less than 90°, the fruit cluster was defined as being in the elongation direction area. If the smaller of the angle between the line segment connecting the center of the fruit cluster and the planting position of the plant and the elongation direction of the primary runner was greater than 90° and 180° or less, the fruit was defined as being in the opposite direction area. For example, in the plant shown in Figure 3, five fruit clusters formed, all of which were formed in the opposite direction area. A similar investigation was conducted on all 30 plants tested, resulting in a total of 111 fruit clusters being investigated. Of these, 91, or approximately 82%, were formed in the opposite direction area. Fruit clusters formed at the boundary between the growth direction area and the opposite direction area (fruit clusters where the smaller angle between the line segment connecting the center of the fruit cluster and the planting position of the plant and the growth direction of the primary runner is 90°) were excluded from the investigation.

[0063] In this embodiment, the "center of the fruit cluster" is defined as the part that is the center of gravity of the multiple fruits in the fruit cluster when viewed from above. An example of the "center of the fruit cluster" is specifically illustrated in Figure 4. For example, when viewing a fruit cluster 15 from above, where a fruit stalk 14 extends from the planting position of the plant, i.e., the base 11, and multiple fruits 151 are formed in a cluster at the end of the stalk, the center of gravity of the approximate curve C formed based on the multiple fruits 151 is considered to be the center of the fruit cluster 150.

[0064] (Example 2: Experiment using conventional soil cultivation) Seeds of the "Yotsuboshi" variety were sown in three batches at approximately two-week intervals, and seedlings were raised in the same manner as in Example 1. Primary runner development was confirmed, and the seedlings were marked. A total of 264 marked seedlings, 142 to 174 days after sowing, were moved half to each of two forced cultivation greenhouses. All seedlings were then transplanted into 30cm high ridges (main fields) for soil cultivation, which were formed inside the forced cultivation greenhouses, and cultivation continued until fruit cluster formation. When transplanting, the direction of the markings made during seedling development was used as a guide, and the seedlings were planted in a staggered two-row pattern so that the direction of primary runner growth was toward the center of the ridge, i.e., the side opposite to the direction in which the label was inserted faced the aisle. All seedlings were also planted perpendicular to the soil surface. After confirming that all seedlings were planted in the specified orientation, the labels were removed from each seedling. After 105 days following transplanting, when fruit cluster formation was confirmed in 72% of the plants, the relationship between the elongation direction of the primary runner and the direction of fruit cluster formation was investigated in each plant using the same method as in Example 1.

[0065] The results are shown in Table 1. In each of the two forced cultivation greenhouses, the planted plants were examined, and in both cases, 75-84% of the fruit clusters formed in the opposite direction area, i.e., the aisle side. Fruit clusters formed at the boundary between the elongation direction area and the opposite direction area were excluded from the study.

[0066] [Table 1]

[0067] These results demonstrate that even when seedlings are planted vertically to the soil surface without being tilted, fruit formation can be controlled with high accuracy in the desired direction by using the direction of primary runner elongation as an indicator. [Industrial applicability]

[0068] This invention can be used in the agricultural field. In particular, it is expected to contribute to improving the efficiency of strawberry production.

Claims

1. A method for cultivating strawberries, A method comprising the step of planting seedlings in a direction specified based on the direction of elongation of the primary runners.

2. The method according to claim 1, further comprising the step of marking the primary runners with an indicator of their elongation direction before planting the seedlings.

3. The method according to claim 1, wherein the primary runner is planted such that the opposite side of its elongation direction is positioned relative to the space for accessing the strawberry.

4. The method according to claim 1, wherein the strawberry is a seed-propagated variety.

5. A method for producing strawberry seedlings, A method comprising the step of marking to indicate the direction of planting.

6. Strawberry seedlings with markings indicating the direction of planting.

7. The seedling according to claim 6, wherein the marking is defined based on the elongation direction of the primary runner.

8. A cultivation container in which multiple strawberry seedlings are planted in a orientation determined based on the direction of elongation of the primary runners.

Images