Dioscorea opposita rejuvenation seedling culture method without bulbil

Abstract

The invention discloses a method for culturing yam rejuvenation seedlings without bulbil. The method comprises the following steps: rejuvenation seedling culture required stem and branch types and specifications, stem and branch rooting and germination induced by a plant growth regulator, seedling culture and a large-scale transplanting technology. According to the method, the plant growth regulator is used for inducing the Chinese yam stems and branches to root and germinate, and then the Chinese yam rejuvenated seedlings are cultured. According to the rejuvenated seedlings cultivated through the method, root-knot nematodes and soil-borne pathogenic bacteria carried by the yam seeds are removed, and the technical problem of rejuvenation of the yam without bulbil is solved; the honeycomb type seedling cup is used for seedling transplanting, secondary transplanting is not needed, the transplanting cost is low, the survival rate reaches up to 89.50%, the labor efficiency is improved, meanwhile, the problem that the survival rate of rejuvenation transplanting of the Chinese yam tissue culture seedlings is low is solved, and large-scale seedling planting is achieved; after the seedlings are transplanted, rejuvenated commercial potatoes are formed in the same year, the problem that the rejuvenation period of bulbil is long is solved, and the rejuvenation period is effectively shortened.

Description

Technical Field

[0001] The invention belongs to the technical field of yam seedling cultivation, and in particular relates to a method for cultivating yam seedlings that do not produce any fruit. Background Art

[0002] Chinese yam is the rhizome of Dioscoreaceae and Dioscorea Linn. It is rich in saponins, mucilage, starch, glycoprotein, amino acids, vitamins and various trace elements. It has the effects of nourishing essence and beauty, anti-tumor, anti-aging, enhancing immune function and regulating endocrine. Most varieties of Chinese yam can be propagated by zero-seedling, while a few varieties cannot form zero-seedling and can only rely on tuber propagation. After years of tuber propagation, the varieties have seriously degenerated, the stress resistance and disease resistance of the varieties have decreased, and the excellent characteristics of the varieties have gradually been lost. The rapid propagation technology of Chinese yam tissue culture is the main technology to solve the degeneration of Chinese yam varieties that do not produce zero-seedlings. However, there are problems such as the difficulty of transplanting survival of Chinese yam tissue culture seedlings, the small size of tissue culture seed potatoes, and the high mutation rate of tissue offspring, which seriously restricts the large-scale and industrialized breeding of Chinese yam seedlings.

[0003] The invention patent with the publication number CN1 16326484A discloses "a method for in vitro cultivation of yam regenerated seedlings from stem segments with axillary buds of yam", which solves the technical problem that the in vitro culture of stem segments of yam with axillary buds directly forms axillary buds instead of a regenerated seedling. However, for yam varieties that do not produce axillary buds, neither axillary buds nor regenerated seedlings are formed when the stem segments are cultured in vitro, let alone commercial potatoes that year. What type of stem branches to choose and how to induce the stem segments with axillary buds to germinate are the problems that need to be solved first. Stems and branches in different parts, stem segments in different parts, and the number of nodes in the stem segments may affect the germination rate and rooting rate of the stem segments. Moreover, the yam that does not produce axillary buds belongs to a different variety, and the cultivation method cannot be directly copied from the method of the yam that produces axillary buds.

[0004] Gibberellic acid synthesis inhibitors (PAC) usually have the effect of inhibiting the formation of yam spores and promoting the germination of stem segments. Naphthaleneacetic acid (NAA) generally has the effect of promoting the rooting of yam stem segments. The combination of the two may promote the germination and rooting of stem segments. How to improve the efficiency of transplanting is also a problem to be solved. If commercial potatoes are to be formed, plug tray transplanting requires secondary transplanting; transplanting in seedbeds and nutrient pots has high transplanting costs and is labor-intensive and time-consuming. Therefore, we improved the existing yam seedling culture method for yam varieties that do not produce spores. Summary of the invention

[0005] The purpose of the present invention is to provide a method for culturing seedlings of non-fruiting yam to be rejuvenated. The present invention clarifies the stem and branch types and transplanting methods for culturing seedlings of non-fruiting yam to be rejuvenated, providing a new approach for rejuvenating non-fruiting yam.

[0006] To achieve the above object, the technical solution of the present invention is as follows:

[0007] A method for culturing rejuvenated seedlings of non-tuberous yam, comprising the following steps:

[0008] (1) Stem branch type and specifications: Select yam branches different from the main stem. The branches are cut into stem segments with axillary buds using scissors, and the axillary buds are healthy and disease-free;

[0009] (2) Inducing rooting and germination of stem segments with plant growth regulators: Immerse the stem segments in step (1) in a plant growth regulator for treatment;

[0010] (3) Seedling cultivation: Suspend the stem segments treated in step (2) in a culture tank filled with 6 - 8 cm of tap water. When the stem segments are planted, the immersion depth of the stem segments in the water surface is 2 - 3 cm, the stem nodes are flush with the water surface, and the leaves of each stem segment do not shade each other; Cultivate to form seedlings with more than 5 roots and germinated axillary buds;

[0011] (4) Seedling transplantation: Prepare a seedbed 1 m wide, apply sufficient base fertilizer to the seedbed, deeply plow and finely harrow, dig the seedbed to a depth of 5 - 7 cm, and break up the soil; Pull the honeycomb-shaped seedling cups while filling them with substrate until the seedling cups are fully unfolded; Plant the seedlings in step (3) in the honeycomb-shaped seedling cups; Water with root-fixing water on the day of transplantation, and then water once every 2 - 3 days. Water in a timely manner after the seedlings survive.

[0012] Preferably, in step (1), the stem segments are selected from the 3rd to 7th nodes from the bottom of the stem branch. The stem segments have 2 nodes, a length of 8 - 9 cm, a length of 2 - 3 cm reserved at the lower part of the stem node, and at least 1 leaf.

[0013] Preferably, the method for treating the plant growth regulator in step (2) is: First immerse the stem segments in a PAC (gibberellin synthesis inhibitor) solution with a concentration of 100 mg / L for 60 minutes, and then immerse them in a NAA (naphthaleneacetic acid) solution with a concentration of 20 mg / L for 10 minutes.

[0014] Preferably, the culture tank is 8 - 10 cm deep and 1 m wide. The temperature for seedling cultivation is controlled at 18 - 32 °C, and the light is mainly diffused light.

[0015] Preferably, the width of the honeycomb-shaped seedling cups in step (4) should be 10 - 12 cm, and the height should be 8 - 10 cm. Advantages of the present invention:

[0016] (1) By improving the number of stem segments, the types and concentrations of plant growth regulators, and the transplanting method, the present invention explores a method for cultivating rejuvenated seedlings of non-tuber-bearing Chinese yams and large-scale transplanting, solves the technical problem of rejuvenating non-tuber-bearing Chinese yams, and provides a new way for rejuvenating non-tuber-bearing Chinese yams. This technology has the advantages of low seedling cultivation cost, high efficiency, simple transplanting, and high survival rate, and provides technical support for the degradation of Chinese yam varieties and the standardized production of healthy seed potatoes.

[0017] (2) Applying honeycomb-shaped seedling cups for large-scale transplanting of seedlings has low transplanting cost, convenient management after transplanting, and does not require secondary transplanting, improving labor efficiency.

[0018] (3) The rejuvenated seedlings cultivated from the stems of non-tuber-bearing Chinese yams can form commercial tubers in the same year after being planted at the appropriate time. The cultivation efficiency is high, the cost is low, and the survival rate is high, solving the problem of the long rejuvenation cycle of tubers and effectively shortening the rejuvenation cycle.

[0019] (4) This technology is easy to operate, overcomes the problem of non-survival of rejuvenated transplanting of Chinese yam tissue seedlings, has no slow seedling after transplanting, and has a high survival rate, providing technical support for the degradation of Chinese yam varieties and the standardized production of healthy seed potatoes. Description of the Drawings

[0020] Figure 1 is the rejuvenated seedling using stem rejuvenation in the embodiment of the present invention. Detailed Embodiments

[0021] The present invention will be further described below in conjunction with specific embodiments, and the advantages and features of the present invention will become clearer as the description progresses. However, the specific experimental methods involved in the following embodiments are all conventional methods or are implemented according to the conditions recommended in the manufacturer's instructions unless otherwise specified.

[0022] Unless otherwise specified, the technical means used in the embodiments are conventional means well known to those skilled in the art. The test methods in the following embodiments are all conventional methods unless otherwise specified. Unless otherwise specified, the reagents and materials used can be obtained from the market.

[0023] Unless otherwise defined, all professional and scientific terms used herein have the same meaning as those familiar to those skilled in the art. In addition, any methods and materials similar or equivalent to the described content can be applied to the present invention. The preferred implementation methods and materials described herein are for illustrative purposes only.

[0024] 1. Test Materials

[0025] The test material is water Chinese yam.

[0026] 2. Test Methods

[0027] 2.1 Effects of Different Types of Stem Branches on the Seedling Establishment Rate of Rejuvenated Seedlings

[0028] Select the branches and main stems of yam vines, cut off the tender tips, cut them into sections by node, each stem section retains 1 node, and each stem node retains 1 or 2 leaves. The stem sections are soaked in 20 mg / L NAA for 10 min for in vitro culture, with water as the control. There are 40 stem sections for each treatment. The rooting rate of the stem sections is investigated every 7 days, and the germination rate of the stem sections is investigated after 28 days.

[0029] 2.2 Effects of Stem Section Positions on the Seedling Establishment Rate of Rejuvenated Seedlings

[0030] Select yam branches, and divide them into tender stems (the second to third nodes from the bottom), middle stem sections (the third to fifth nodes from the bottom), and lower stem sections (the fifth to seventh nodes from the bottom) according to the stem section positions. The second to third nodes of the tender stems are not segmented, and the remaining stem sections are cultured by separating them into single-stem sections. Each stem node retains 1 or 2 leaves, and they are soaked in rooting powder and 20 mg / L NAA for 10 min respectively for in vitro culture, with water as the control. There are 40 stem sections for each treatment. The rooting rate of the stem sections is investigated every 7 days, and the germination rate of the stem sections is investigated after 28 days.

[0031] 2.3 Effects of the Number of Stem Nodes on the Seedling Establishment Rate of Rejuvenated Seedlings

[0032] Select yam branches, after cutting off the second to third nodes from the bottom, cut the stem branches into single-node and double-node sections respectively, and then soak them in 20 mg / L NAA for 10 min for in vitro culture. There are 40 stem sections for each treatment. The rooting rate of the stem sections is investigated every 7 days, and the germination rate of the stem sections is investigated after 28 days.

[0033] 2.4 Effects of the Number of Stem Nodes on the Transplanting Survival Rate of Rejuvenated Seedlings

[0034] The rejuvenated seedlings are transplanted into the seedbed according to the second to third nodes from the bottom, single-node and double-node. There are 30 stem sections for each treatment, and the transplanting survival rate is calculated 14 days after transplantation.

[0035] 2.5 Effects of the Treatment Concentration and Time of Plant Growth Regulator NAA on the Seedling Establishment Rate of Rejuvenated Seedlings

[0036] Select yam branches, after cutting off the second to third nodes from the bottom, cut the remaining stem sections into sections with 2 stem nodes, and each stem node retains 1 or 2 leaves. The stem sections are soaked in NAA treatment solutions with different concentrations and times for in vitro culture. There are 40 stem sections for each treatment. The rooting rate of the stem sections is investigated every 7 days, and the germination rate of the stem sections is investigated after 28 days. The specific treatments are as follows:

[0037] ck: The stem sections are not soaked;

[0038] Treatment 1: The stem sections are soaked in 20 mg / L NAA for 10 min;

[0039] Treatment 2: The stem sections are soaked in 20 mg / L NAA for 20 min;

[0040] Treatment 3: The stem segments were soaked in 40 mg / L NAA for 10 min.

[0041] 2.6 Effect of Plant Growth Regulator Types on the Seedling Establishment Rate of Rejuvenated Seedlings

[0042] Select yam branches, take every two nodes as one stem segment for in vitro culture, and retain 1 or 2 leaves on each stem node. After the stem segments were soaked in different types of growth regulators, they were subjected to in vitro culture. There were 65 stem segments for each treatment. The rooting rate of the stem segments was investigated every 7 days, and the germination rate of the stem segments was investigated after 28 days. The specific treatments were as follows:

[0043] Treatment 1: The stem segments were soaked in 20 mg / L NAA for 10 min;

[0044] Treatment 2: The stem segments were soaked in 100 mg / L PAC for 60 min;

[0045] Treatment 3: The stem segments were soaked in 100 mg / L PAC for 60 min and then soaked in 20 mg / L NAA for 10 min.

[0046] 2.7 Cost Accounting of Different Transplanting Methods

[0047] The rejuvenated seedlings were transplanted using honeycomb-shaped seedling cups and nutrient pots respectively. The transplanting survival rate was calculated after 30 days of transplanting, and the transplanting cost was accounted.

[0048] 3. Experimental Results

[0049] 3.1 Effect of Different Types of Stem Branches on the Seedling Establishment Rate of Rejuvenated Stem Segment Seedlings

[0050] The results showed (Table 1) that for the stem segments cut from yam branches, the rooting rate and germination rate were both higher than those of the main yam stem. It is advisable to use yam branches for cultivating rejuvenated seedlings.

[0051] Table 1 Effect of Different Types of Stem Branches on the Seedling Establishment Rate of Rejuvenated Seedlings

[0052]

[0053] 3.2 Effect of Different Stem Segment Positions on the Seedling Establishment Rate of Rejuvenated Seedlings

[0054] The results showed (Table 2) that when cultured for 7 days, adventitious roots began to grow on the tender stems and middle stem segments. When cultured for 21 days, for the treatment with 20 mg / L NAA, the control with the 2nd - 3rd inverted nodes had the highest rooting rate and germination rate, which were 93.33% and 46.15% respectively. The rooting rate and germination rate of the 3rd - 5th inverted nodes were higher than those of the 2nd - 3rd inverted nodes. For the treatment with 20 mg / L NAA, the rooting rate of the 3rd - 5th inverted nodes was 72.73% and the germination rate was 33.33%. Since the number of the 2nd - 3rd inverted nodes is small and they are prone to death, the stem segments of the 3rd - 7th inverted nodes should be selected for seedling cultivation after being soaked in NAA for 10 minutes.

[0055] Table 2 Effect of Different Stem Segment Positions on the Seedling Establishment Rate of Rejuvenated Seedlings

[0056]

[0057] 3.3 Effect of the Number of Stem Segment Nodes on the Seedling Establishment Rate of Rejuvenated Seedlings

[0058] The results showed (Table 3) that when cultured for 21 days, there was little difference in the rooting rate between the double - node stem segments and the single - node stem segments. When cultured for 28 days, the germination rate of the double - node stem segments was higher than that of the single - node stem segments, and the germination rate was 50.00%.

[0059] Table 3 Effect of the Number of Stem Segment Nodes on the Seedling Establishment Rate of Rejuvenated Seedlings

[0060]

[0061] 3.4 Effect of the Number of Stem Segment Nodes on the Transplanting Survival Rate of Rejuvenated Seedlings

[0062] The results of transplanting for 14 days showed (Table 4) that the double - node rejuvenated seedlings had the highest transplanting survival rate, which was 89.50%. Therefore, double - node stem segments should be selected for the cultivation of rejuvenated seedlings of water yam.

[0063] Table 4 Transplanting of Rejuvenated Seedlings

[0064]

[0065] 3.5 Effect of the Treatment Concentration and Time of Plant Growth Regulator NAA on the Seedling Establishment Rate of Stem Segment Rejuvenated Seedlings

[0066] The results showed (Table 5) that when cultured for 28 days, the stem segments were soaked in 20 mg / L NAA for 10 minutes, and the rooting rate and germination rate of the stem segments were the highest, which were 62.50% and 52.50% respectively. Increasing the NAA concentration and soaking time had little effect on the seedling establishment rate of the seedlings.

[0067] Table 5 Effect of the Treatment Concentration and Time of Plant Growth Regulator NAA on the Seedling Establishment Rate of Stem Segment Rejuvenated Seedlings

[0068]

[0069] 3.6 Effects of Types of Plant Growth Regulators on the Seedling Establishment Rate of Rejuvenated Seedlings

[0070] The results after 28 days of culture showed (Table 6) that when the stem segments were soaked in PAC for 60 min and then in NAA for 10 min, the rooting rate and germination rate of the stem segments were the highest, reaching 89.23% and 64.46% respectively.

[0071] Table 6 Effects of Types of Plant Growth Regulators on the Seedling Establishment Rate of Rejuvenated Seedlings

[0072]

[0073] 3.7 Cost Accounting of Different Transplanting Methods

[0074] When rejuvenated seedlings were transplanted using honeycomb-shaped seedling cups and nutrient pots respectively, at 30 days after transplantation, the seedling survival rates were 89.50 and 69.23% respectively (Table 7). Transplanting with honeycomb-shaped seedling cups was convenient for later management and could improve the seedling survival rate. When other management and planting costs remained unchanged, 20,000 honeycomb-shaped seedling cups could be filled per person per day, while only 2,000 nutrient pots of the same size could be filled, which could save a large amount of labor costs. The total savings in consumables and labor costs was approximately 19.23%.

[0075] Table 7 Effects of Types of Plant Growth Regulators on the Seedling Establishment Rate of Rejuvenated Seedlings

[0076]

[0077] The above-described embodiments are only preferred embodiments of the present invention, which are only used to explain the present invention and do not limit the scope of implementation of the present invention. For those skilled in the art of this technology, other implementation methods can of course be easily made by means of substitution or change according to the technical content disclosed in this specification. Therefore, all changes and improvements made on the principle of the present invention should be included within the scope of the patent application of the present invention.

Claims

1. A method for rejuvenating seedlings of non-fruiting yam, characterized in that: The method comprises the following steps: (1) Stem and branch type and specifications: Select yam branches that are different from the main stem, and the branches are cut into stem segments with axillary buds using scissors. The axillary buds are healthy and disease-free. (2) inducing the stem segments to root and sprout with plant growth regulators: soaking the stem segments obtained in step (1) in a plant growth regulator; (3) seedling cultivation: the stem segments treated in step (2) are suspended and cultivated in a cultivation tank, wherein tap water is placed 6 to 8 cm in the cultivation tank; when the stem segments are planted, the stem segments are immersed in the water surface to a depth of 2 to 3 cm, the stem nodes are flush with the horizontal plane, and the leaves of each stem segment do not block light from each other; and the cultivation forms seedlings with more than 5 root systems and axillary buds; (4) Transplanting seedlings: prepare a 1m wide seedbed, apply sufficient basal fertilizer to the seedbed, deep plow and harrow, dig the seedbed to a depth of 5 to 7cm, and break up the soil; pull the honeycomb seedling cup while filling it with substrate until the seedling cup is fully expanded; plant the seedlings from step (3) in the honeycomb seedling cup; water the seedlings on the day of transplanting to establish roots, and water them every 2 to 3 days thereafter. Water the seedlings in time after they are established.

2. The method for culturing seedlings of non-fruiting yam according to claim 1, characterized in that: The stem segment of step (1) is selected from the 3rd to 7th nodes of the stem branch, the stem segment has 2 nodes, a length of 8 to 9 cm, a length of 2 to 3 cm is retained below the node, and the stem segment has at least one leaf.

3. The method for culturing seedlings of non-fruiting yam according to claim 1, characterized in that: The specific method of the plant growth regulator treatment in step (2) is: firstly soaking the stem segment in a 100 mg / L PAC solution for 60 min, and then soaking it in a 20 mg / L NAA solution for 10 min.

4. The method for culturing seedlings of non-fruiting yam according to claim 1, characterized in that: The culture tank is 8 to 10 cm deep and 1 m wide.

5. The method for culturing seedlings of non-fruiting yam according to claim 1 or 4, characterized in that: The temperature for seedling cultivation is controlled at 18-32℃, and the light is mainly scattered light.

6. The method for culturing seedlings of non-fruiting yam according to claim 1, characterized in that: The honeycomb seedling raising cup in step (4) has a width of 10 to 12 cm and a height of 8 to 10 cm.

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