Method for grafting of thin-skinned melon and application thereof

Abstract

The application belongs to the technical field of grafting planting, and particularly relates to a thin-skinned muskmelon grafting method and application thereof. The application adopts the grafting method, when the stock is grown to the 1-leaf 1-heart stage, the thin-skinned muskmelon is grown to the stage of cotyledon straightening to 45 DEG, the cotyledon node of the thin-skinned muskmelon is cut into an inclined surface at an angle of about 45 DEG downward at a position 0.5 cm below the cotyledon node, a thin-skinned muskmelon scion is obtained, and grafting is started; when grafting, the stock is hearted, true leaves are removed, and leaf stalks are reserved; the first true leaf of the stock is at an angle > 40 DEG with the ground surface. The application is simple in operation, reduces the pressure on the scion by using the leaf stalk of the stock, reduces the contact of the scion with the film, thereby improving the survival rate and seedling rate of grafting, reducing the loss of diseases, scion rotting and the like, is low in cost, and can improve the grafting seedling benefit.

Description

Technical Field

[0001] This invention belongs to the field of grafting cultivation technology, specifically relating to a grafting method for thin-skinned melons and its application. Background Technology

[0002] Muskmelon is a widely cultivated economic crop among cucurbits, with my country ranking first globally in both cultivation area and yield, playing a vital role in national economic development. However, continuous cropping obstacles caused by diseases like Fusarium wilt are a significant factor restricting the production of major cucurbit varieties. Grafting is one of the most economical and effective methods to address these obstacles. Currently, pumpkin rootstock is the primary grafting rootstock for muskmelon. During the healing process after grafting, the graft union is primarily maintained by covering the seedling with a thin film to retain warmth and moisture, ensuring proper healing. However, muskmelon, especially thin-skinned varieties, often has relatively thin and weak scions. The high temperature and humidity of the grafting environment increase the weight of the film due to the large amount of moisture inside, easily compressing the scion and causing it to bend. Furthermore, lifting the film during the healing stage can lead to misalignment at the graft union, preventing the rootstock and scion from forming a callus and thus reducing the grafting survival rate. Alternatively, an insufficiently small graft union can result in weak seedlings that survive, or die or grow poorly due to limitations in water and nutrient absorption and transport during field growth. In addition, the high temperature and humidity in the grafted seedling environment and the large-area contact between the film and the scion increase the risk of water droplets accumulating on the scion or flowing along the scion to the rootstock-scion junction, thereby increasing the risk of diseases and rot caused by water accumulation. Summary of the Invention

[0003] The purpose of this invention is to overcome the shortcomings of existing melon grafting methods and provide a simple, low-cost, high survival rate and high seedling vigor grafting method for thin-skinned melons.

[0004] This invention provides a method for grafting thin-skinned melons, comprising the following steps:

[0005] When the rootstock grows to the 1-leaf-1-heart stage and the thin-skinned melon grows to the point where the cotyledons are upright or spread at 45°, cut a slanted surface at about 45° downwards 0.5cm below the cotyledon node of the thin-skinned melon to obtain the thin-skinned melon scion, and begin grafting.

[0006] During grafting, the rootstock is pruned, the true leaves are removed, and the petioles are retained;

[0007] The grafting method includes the insertion grafting method;

[0008] The angle between the petiole of the first true leaf of the rootstock and the ground surface is greater than 40°.

[0009] Preferably, the rootstock variety includes pumpkin.

[0010] Preferably, the pumpkin includes Sizhuang No. 7 or Sizhuang No. 12.

[0011] Preferably, the method for obtaining the rootstock includes: soaking the rootstock seeds for 2-6 hours, germinating them at 25-30℃, and sowing and cultivating the rootstock seeds when they sprout.

[0012] Preferably, the method for obtaining the thin-skinned melon scions includes: soaking the thin-skinned melon seeds for 1-4 hours and then sowing them, and cultivating them at 25-30℃.

[0013] Preferably, the sowing method includes direct seeding;

[0014] After soaking, and before sowing, the thin-skinned melon seeds are germinated at 25–30°C.

[0015] Preferably, the grafting process also includes management before the graft survives.

[0016] Preferably, the management method includes: after grafting, placing the grafted seedlings in a seedbed or seedling rack for heat preservation and moisture retention treatment, with the temperature controlled at 25-30℃ and the humidity controlled at 80-95%.

[0017] This invention also provides the application of the thin-skinned melon grafting method described above in the cultivation of thin-skinned melons.

[0018] Beneficial effects:

[0019] This invention employs a grafting method. When the rootstock reaches the 1-leaf-1-heart stage and the thin-skinned melon grows to the point where the cotyledons are upright or spread at 45°, a slanted cut is made at approximately 45° angle downwards 0.5cm below the cotyledon node of the thin-skinned melon to obtain the thin-skinned melon scion, and grafting begins. During grafting, the rootstock is pruned, the true leaves are removed, and the petioles are retained. The angle between the petiole of the first true leaf of the rootstock and the ground surface is limited to >40°. The operation is simple, and the use of the rootstock petiole reduces the pressure on the scion and the contact between the scion and the film, thereby improving the survival rate and seedling vigor of grafting, reducing losses such as diseases, and having low cost, which can improve the efficiency of grafting seedling cultivation. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the accompanying drawings used in the embodiments will be briefly described below.

[0021] Figure 1 This is a schematic diagram of step 2.3 of Example 1, in which a toothpick is inserted at an angle of approximately 45° downwards at the base of the cotyledon on one side of the rootstock to form a toothpick hole.

[0022] Figure 2 The grafted seedlings obtained in step 2.3 of Example 1. Detailed Implementation

[0023] This invention provides a method for grafting thin-skinned melons, comprising the following steps:

[0024] When the rootstock grows to the 1-leaf-1-heart stage and the thin-skinned melon grows to the point where the cotyledons are upright or spread at 45°, cut a slanted surface at about 45° downwards 0.5cm below the cotyledon node of the thin-skinned melon to obtain the thin-skinned melon scion, and begin grafting.

[0025] During grafting, the rootstock is pruned, the true leaves are removed, and the petioles are retained;

[0026] The grafting method includes the insertion grafting method;

[0027] The angle between the petiole of the first true leaf of the rootstock and the ground surface is greater than 40°.

[0028] This invention preferably cultivates rootstock seeds to obtain rootstocks. The cultivation method includes: soaking rootstock seeds for 2-6 hours, germinating them at 25-30°C, and sowing and cultivating the germinated seeds. Preferably, the soaking time is 4 hours; the germination temperature is preferably 28°C. In this embodiment, preferably, when more than 85% of the rootstock seeds have germinated, the germinated seeds are selected for sowing and cultivated according to conventional methods until the 1-leaf-1-heart stage to obtain the rootstock. This invention does not have strict requirements on the cultivation method; conventional cultivation methods in the art are acceptable. The angle between the petiole of the first true leaf of the rootstock and the ground surface is preferably >40° and <90°. Preferably, the germinated rootstock seeds are sown in 50-cell trays filled with seedling substrate. This invention does not have strict requirements on the source of the seedling substrate; conventional purchase is acceptable. The seedling substrate used in this embodiment was purchased from Hangzhou Kangcheng Agricultural Technology Co., Ltd.

[0029] In this invention, the rootstock variety is preferably pumpkin, and more preferably Sizhuang No. 7 or Sizhuang No. 12.

[0030] This invention preferably cultivates thin-skinned melon seeds. The cultivation method includes soaking the thin-skinned melon seeds for 1-4 hours, then sowing them, and cultivating them at 25-30℃. Preferably, the soaking time is 2 hours; the cultivation temperature is preferably 28℃. This invention does not have strict requirements on the cultivation method; conventional methods in the art can be used to cultivate the thin-skinned melon seeds until the cotyledons are upright to about 45° fully expanded, preferably until the cotyledons are upright and about to expand.

[0031] In this invention, direct sowing is preferred. In this embodiment, seeds can be sown immediately after soaking, or they can be soaked at 25-30°C to germinate the thin-skinned melon seeds. When more than 85% of the thin-skinned melon seeds have germinated, the germinated seeds are selected for sowing. Preferably, the germinated thin-skinned melon seeds are sown in square trays filled with seedling substrate. This invention does not have strict requirements regarding the source of the seedling substrate; conventional purchases are acceptable. The seedling substrate used in this embodiment was purchased from Hangzhou Kangcheng Agricultural Technology Co., Ltd.

[0032] The cultivation process described in this invention is completed when the thin-skinned melon has grown to the point where the cotyledons are upright to about 45° fully expanded, preferably when the cotyledons are about to fully expand. At this point, a slanted cut is made at approximately 45° angle downwards, 0.5 cm below the cotyledon node, to obtain the thin-skinned melon scion. The hypocotyl length of the thin-skinned melon scion is preferably 1.0–3.0 cm, more preferably 2.0 cm; the hypocotyl thickness is preferably 0.2–0.4 cm, more preferably 0.3 cm. In this embodiment, Fengcui No. 1 is used as an example, but this should not be construed as representing the entire scope of protection of this invention.

[0033] After obtaining the rootstock and the thin-skinned melon scion, the present invention removes the terminal bud and true leaves from the rootstock, retaining the petioles. The thin-skinned melon scion is then grafted onto the cotyledon node of the rootstock using a grafting method to obtain a grafted seedling. Preferably, all petioles are retained. The grafting method is not strictly required; conventional procedures are sufficient.

[0034] After obtaining the grafted seedlings, the present invention preferably manages the grafted seedlings. The management method of the present invention preferably includes: placing the grafted seedlings in a seedbed or seedling rack and performing heat and moisture retention treatment; the heat and moisture retention treatment preferably controls the temperature at 25-30℃, more preferably 28℃; the heat and moisture retention treatment preferably controls the humidity at 80-95%, more preferably 85-90%. The heat and moisture retention treatment of the present invention preferably includes covering with a thin film.

[0035] This invention uses rootstock with an angle greater than 40° between the petiole of the first true leaf and the ground surface as material. When the rootstock grows to the 1-leaf-1-heart stage, the heart is removed, and the true leaves are removed, leaving only the petiole. The petiole is used to reduce the pressure on the thin-skinned melon scion and reduce the contact between the thin-skinned melon scion and the film, which can improve the grafting survival rate and seedling vigor rate, reduce the occurrence of diseases and weak seedlings (seedlings in a sub-healthy state), and is simple to operate, low in cost, and can improve the efficiency of grafting and seedling cultivation.

[0036] This invention also provides the application of the thin-skinned melon grafting method described above in the cultivation of thin-skinned melons. This invention does not impose strict requirements on the cultivation method; the surviving grafted seedlings obtained through the described thin-skinned melon grafting method are transplanted into the field and cultivated using conventional methods.

[0037] To further illustrate the present invention, the following detailed description of a thin-skinned melon grafting method and its application provided by the present invention is provided in conjunction with embodiments, but these should not be construed as limiting the scope of protection of the present invention.

[0038] Example 1

[0039] 1. Materials: Pumpkin rootstock variety Sizhuang No. 7, thin-skinned melon variety Fengcui No. 1, both of which are commercial varieties and available from Ningbo Fengdeng Seed Industry Technology Co., Ltd.

[0040] 2. Grafting method: The experiment was conducted in Ningbo High-tech Agricultural Technology Experimental Park, with a treatment group and a control group.

[0041] 2.1 Obtaining rootstock for grafting consists of the following steps:

[0042] Soak the seeds of Sizhuang No. 7 for 4 hours, germinate them at 28℃, and after germination, sow them in 50-cell trays filled with seedling substrate (purchased from Hangzhou Kangcheng Agricultural Technology Co., Ltd.), one seed per cell. About 10 days after sowing, select seedlings that have grown to one leaf and one heart, with the petiole of the first true leaf forming an angle greater than 40° with the ground surface (i.e., horizontal plane), as rootstocks for grafting, and keep them ready for use.

[0043] 2.2 Obtaining scions for grafting consists of the following steps:

[0044] After soaking the seeds of Fengcui No. 1 for 2 hours, germinate them at 26℃. After germination, sow them in square trays containing seedling substrate (purchased from Hangzhou Kangcheng Agricultural Technology Co., Ltd.). Seedlings will emerge about 5 days after sowing. Select seedlings that have grown to the point where the cotyledons are about to unfold, with a hypocotyl length of 1.0-3.0cm and a diameter of 0.2-0.4cm. Cut the seedlings at an angle of about 45° downwards 0.5cm below the cotyledon node to make scions for grafting.

[0045] 2.3 The grafting method consists of the following steps:

[0046] Treatment group: In step 2.1, use sterilized scissors to cut off the true leaves from the base of the rootstock, leaving all petioles, and remove the heart by hand; insert a bamboo skewer at an angle of about 45° downwards from the base of the cotyledons on one side of the rootstock, with the tip of the skewer protruding at the hypocotyl. Figure 1 Remove the bamboo skewer, and insert the scion obtained in step 2.2, with the slanted side facing down, into the hole where the bamboo skewer was inserted to obtain a grafted seedling. Figure 2 );

[0047] Control group: The rootstock obtained in step 2.1 was completely stripped of its true leaves, petioles, and heartwood using sterilized scissors, leaving only the hypocotyl and cotyledons. A bamboo skewer was inserted diagonally downwards at about a 45° angle from the base of the cotyledons on one side of the rootstock, with the tip of the skewer protruding at the hypocotyl. The skewer was then removed, and the scion obtained in step 2.2 was inserted diagonally downwards into the hole where the skewer was inserted to obtain a grafted seedling.

[0048] After grafting was completed in both the treatment and control groups, the grafted seedlings were placed in the seedbed and covered with a thin film to keep them warm at 25-30℃ and moist at over 85%. The remaining management was the same as that for conventional grafting seedling cultivation.

[0049] Example 2

[0050] 1. Materials: Pumpkin rootstock variety Sizhuang 12, thin-skinned melon variety Fengcui 1, both commercial varieties, available from Ningbo Fengdeng Seed Industry Technology Co., Ltd.;

[0051] Pumpkin rootstock variety LN0817 (“Screening of different types of salt-tolerant pumpkin materials, Chinese Vegetables, 2017, 30(6): 9-13”, is a material with an angle of about 30° between the petiole of the first true leaf and the ground surface).

[0052] 2. Grafting method: The experiment was conducted in Ningbo High-tech Agricultural Technology Experimental Park, with a treatment group, control group 1, and control group 2.

[0053] 2.1 Obtaining rootstocks for grafting of the treatment group consists of the following steps:

[0054] Sizhuang No. 7 seeds were soaked for 4 hours and germinated at 28℃. After germination, they were sown in 50-cell trays filled with seedling substrate (purchased from Hangzhou Kangcheng Agricultural Technology Co., Ltd., product number 1). One seed was sown in each cell. About 10 days after sowing, seedlings that had grown to one leaf and one heart, with the petiole of the first true leaf forming an angle greater than 40° with the ground surface, were selected as rootstocks for grafting in the treatment group and kept for later use.

[0055] 2.2 The acquisition of rootstocks for grafting in control group 1 and control group 2 consisted of the following steps:

[0056] LN0817 seeds were soaked for 4 hours and germinated at 28℃. After germination, they were sown in 50-cell trays filled with seedling substrate (purchased from Hangzhou Kangcheng Agricultural Technology Co., Ltd., product number 1). One seed was sown in each cell. About 10 days after sowing, seedlings that had grown to one leaf and one heart, with the petiole of the first true leaf forming an angle of about 30° with the ground surface, were selected as rootstocks for grafting in the control group.

[0057] 2.3 Obtaining scions for grafting consists of the following steps:

[0058] After soaking the seeds of Fengcui No. 1 for 2 hours, germinate them at 26℃. After germination, sow them in square trays containing seedling substrate (purchased from Hangzhou Kangcheng Agricultural Technology Co., Ltd., product number). Seedlings will emerge about 5 days after sowing. Select seedlings that have grown to the point where the cotyledons are about to unfold, with a hypocotyl length of 1.0-3.0cm and a diameter of 0.2-0.4cm. Cut the seedlings at an angle of about 45° downwards 0.5cm below the cotyledon node to make scions for grafting.

[0059] 2.4 The grafting method consists of the following steps:

[0060] Treatment group: In step 2.1, use sterilized scissors to cut off the leaves from the base of the true leaves of the rootstock, leaving all the petioles, and remove the heart by hand; insert a bamboo stick diagonally downward at about 45° from the base of the cotyledons on one side of the rootstock, with the tip of the bamboo stick protruding at the hypocotyl, pull out the bamboo stick, and insert the scion obtained in step 2.3 with the slanted side down into the hole inserted by the bamboo stick to obtain the grafted seedling;

[0061] Control Group 1: In step 2.2, the rootstock was cut off from the base of the true leaves using sterilized scissors, leaving all the petioles, and the heart was removed by hand; a bamboo stick was inserted diagonally downward at about 45° from the base of the cotyledons on one side of the rootstock, with the tip of the bamboo stick protruding at the hypocotyl, the bamboo stick was pulled out, and the scion obtained in step 2.3 was inserted into the hole of the bamboo stick with the slanted side facing down, to obtain the grafted seedling;

[0062] Control Group 2: In step 2.1, remove all the true leaves, petioles and heart of the rootstock by hand, leaving only the hypocotyl and cotyledons; insert a bamboo stick at an angle of about 45° downward from the base of the cotyledons on one side of the rootstock, with the tip of the bamboo stick protruding at the hypocotyl; remove the bamboo stick, and insert the scion obtained in step 2.3 with the slanted side down into the hole where the bamboo stick was inserted to obtain the grafted seedling.

[0063] After grafting was completed in the treatment group, control group 1, and control group 2, the grafted seedlings were placed in the seedbed and covered with a thin film to keep them warm and moist. The rest of the management was the same as that of conventional grafting seedling cultivation.

[0064] Test Example 1

[0065] In Examples 1 and 2, 20 days after grafting, the number and survival rate of grafted seedlings obtained from each treatment group were counted, as well as the number of diseased seedlings and strong seedlings after 20 days of grafting. The results are shown in Table 1 below.

[0066] Among them, the criteria for judging diseased seedlings are the presence of seedling diseases such as damping-off and blight; the criteria for judging strong seedlings are that grafted seedlings do not grow excessively, are free from diseases, grow steadily, and have no yellowing of leaves or other adverse symptoms.

[0067] Table 1. Growth of grafted seedlings obtained under different treatments

[0068]

[0069] As shown in Table 1, when grafting with Sizhuang No. 7 and Sizhuang No. 12 as rootstocks, the survival rate and robust seedling rate of the treatment group were higher than those of the control group, while the incidence of diseased and weak seedlings was lower. This indicates that the grafting method of removing the core and retaining the petiole of the present invention can significantly improve the grafting survival rate and robust seedling rate of thin-skinned melons, and reduce the incidence of diseases and weak seedlings. When the grafting method is the same, the growth of grafted seedlings is also different when the angle between the petiole of the first true leaf of the rootstock and the ground surface is different. When the angle is greater than 40°, the survival rate and robust seedling rate of grafted seedlings are higher than those obtained by grafting with rootstocks with an angle of less than 30°, and the incidence of diseases and weak seedlings is lower. This indicates that rootstocks with too small an angle between the first true leaf and the ground surface are not suitable for grafting using the petiole-retaining method. The present invention's limitation of the angle between the first true leaf and the ground surface can improve the grafting survival rate and robust seedling rate, and reduce the occurrence of diseases and the proportion of weak seedlings.

[0070] As can be seen from the above, the grafting method provided by this invention can improve the survival rate and seedling vigor rate of grafted seedlings, and reduce the incidence of diseases and rot in grafted seedlings.

[0071] Although the above embodiments have provided a detailed description of the present invention, they are only some embodiments of the present invention, and not all embodiments. People can obtain other embodiments based on these embodiments without creative effort, and these embodiments all fall within the protection scope of the present invention.

Claims

1. A method for grafting thin-skinned melons, characterized in that, It consists of the following steps: When the stock is grown to 1 leaf 1 heart stage, the thin-skinned melon is grown to cotyledon straight to unfold 45 ° between, the cotyledon node of thin-skinned melon is cut to be bevelled at 0.5 cm position under the cotyledon node, about 45 ° angle, get the thin-skinned melon scion, start grafting; During grafting, the rootstock is pruned, the true leaves are removed, and the petioles are retained; The grafting method is the insertion grafting method; The angle between the petiole of the first true leaf of the rootstock and the ground surface is >40°. ° and <90 ° ; The grafting process also includes management before the graft survives; The management method before survival is as follows: After grafting, place the grafted seedlings in a seedbed or seedling rack, and carry out heat preservation and moisture retention treatment, with the temperature controlled at 25~30℃ and the humidity controlled at 80~95%; The rootstock variety is pumpkin.

2. The method for grafting thin-skinned melons according to claim 1, characterized in that, The pumpkins mentioned include Sizhuang No. 7 or Sizhuang No.

12.

3. The method for grafting thin-skinned melons according to claim 1, characterized in that, The method for obtaining the rootstock includes: soaking the rootstock seeds for 2-6 hours, germinating them at 25-30℃, and sowing and cultivating them when the rootstock seeds sprout.

4. The method for grafting thin-skinned melons according to claim 1, characterized in that, The method for obtaining thin-skinned melon scions includes: soaking thin-skinned melon seeds for 1-4 hours before sowing and cultivating at 25-30℃.

5. The method for grafting thin-skinned melons according to claim 4, characterized in that, The sowing method includes direct seeding; After soaking, and before sowing, the thin-skinned melon seeds are germinated at 25-30℃.

6. The application of the thin-skinned melon grafting method according to any one of claims 1 to 5 in the cultivation of thin-skinned melons.

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