JP2021185763A - Method for promoting seed germination of poorly-germinated plant - Google Patents

Abstract

To provide a method for promoting the seed germination of poorly-germinated plants such as Viburnum dilatatum and Styrax japonica and shortening the time for raising seedlings, thereby achieving the stable supply of seedlings.SOLUTION: A seed of a poorly-germinated plant is subjected to warm stratification procedure under constant temperature conditions about room temperature with soil including humic matter as a medium; the seed after the warm stratification procedure is sown in a seedbed; the seedbed is subjected to light-dark procedure repeatedly up to its rooting under high temperature-light conditions and low temperature-dark conditions; the rooting seed is subjected to cold stratification procedure under constant temperature and dark conditions at low temperature about the winter temperature; the seed after the cold stratification procedure is cultured at temperatures from the spring to the early summer for germination.SELECTED DRAWING: Figure 6

Description

The present invention relates to a technique for plant cultivation methods. In particular, it relates to germination of seeds of plants that require a long period of time to germinate.

Plant seeds germinate depending on the germination process and environment. Seeds may have the property of dormancy, which does not germinate even under conditions suitable for germination, and some seeds do not germinate even when sown. In order to germinate the seeds of these plants, it is necessary to release the dormancy conditions peculiar to each plant. For example, in dormancy, seeds that should germinate in spring germinate in autumn, which is similar to the environment, and die during winter by processing so that seeds that should germinate in spring do not germinate until the low temperature in winter has passed even if they bear fruit in autumn. It has a defensive function of preventing germination, but it is an obstacle to controlling germination. Therefore, various dormancy breaks have been developed to artificially promote the use of plants.
In today's agricultural and other plant cultivation, dormancy hinders cultivation at any time, so varieties without dormancy or with a short dormancy period are also being cultivated. Methods have also been developed to break plant dormancy by applying artificial treatment.

Among the native trees, tree species such as viburnum and Styrax japonicum are a form of morphological and physiological dormancy and have the property of epicotyl dormancy, which is a very deep dormancy. It is known that seeds are formed while the embryos are immature, and the seeds are dormant until the embryos mature and are suitable for germination, and it takes a long time to germinate. For example, viburnum seeds are collected from October to December, but if they are carefully selected by removing the pulp and then sown outdoors, or if they are stored at low temperature and then sown in the nursery in the spring, they will germinate the following year. It will be spring (almost one and a half years after sowing). Plants with epicotyl dormancy include erythronium and Anemone nikoensis.
In general, a method called wet layer treatment is often used to promote the germination of deeply dormant seeds. It is a method of wrapping seeds in moistened cotton wool or sand, storing them at a cold temperature of 0 to 5 ° C for several months (cold / hot wet layer treatment), and then sowing. In addition, before applying the cold / hot / wet layer treatment, a warm / hot / wet layer treatment that heats at a temperature of about 15 to 35 ° C. for a certain period may be combined. However, in the case of viburnum dilatatum, it is reported that after 180 to 240 days of warm and warm wet layer treatment for rooting, and then 90 days of cold and warm wet layer treatment, germination finally occurs. That is, it takes 270 to 330 days for viburnum to germinate even if it is treated with a wet layer. Reference 1 Giersbach J. (1937) Germination and seedling production of species Viburnum. Contribution from Boyce Thompson Institute, 9: 79-90.
On the other hand, plant-derived compounds are known to promote seed germination. For example, it has been reported that humic acid, which dissolves in alkali and is insoluble at pH 2 or less, promotes germination of wheat seeds among the humus produced by the decomposition of organic matter derived from animals and plants accumulated in soil by microorganisms. Reference 2 Hassan Ali, et al. (2014) Effect of humic acid on root elongation and percent seed germination of wheat seeds. International Journal of Agriculture and Crop Sciences, 196-201.
Further, Patent Document 1 recognizes that an aqueous solution of a component produced in the process or a component eluted from the wood, that is, a so-called wood vinegar solution, which is heated at a temperature at which the wood is not carbonized, also promotes seed germination.
Patent Document 2 has developed a method for promoting germination of rice seeds by immersing or spraying rice seeds in water containing a compound such as anidine or thiamethoxam.
It is not stated whether these compounds break the dormancy of seeds with morphological and physiological dormancy and promote germination.

Giersbach J. (1937) Germination and seedling production of species Viburnum. Contribution from Boyce Thompson Institute, 9: 79-90. Hassan Ali, et al. (2014) Effect of humic acid on root elongation and percent seed germination of wheat seeds. International Journal of Agriculture and Crop Sciences, 196-201.

Japanese Unexamined Patent Publication No. 2003-146821 Japanese Unexamined Patent Publication No. 2014-1197

The present invention requires more than one and a half years from seed collection to germination without human intervention, and is suitable for epicotyl dormancy and germination-resistant turtles and egonoki. It provides a method for promoting seed germination and shortening the seedling raising period at any time, and aims at a stable supply of seedlings.

In the process of studying a method for promoting germination of caterpillars, the present inventors wrap it in Andosols or red soil containing a large amount of humus and treat it with a warm and warm wet layer, and the period required for rooting is longer than when it is wrapped in sand. It was clarified that the rooting promoting effect did not change even if sterilized Andosols were used. Based on the results, by wrapping the seeds in soil containing a large amount of humus or soil containing humic acid and treating them with a warm, warm and moist layer, the germination of tree seeds having morphological and physiological dormancy such as turtles is promoted. I came to develop a method.
The main configurations of the present invention are as follows.
1. 1. Seeds of plants that are difficult to germinate,
A warm and warm wet layer treatment using soil containing humus as a medium is performed under constant temperature conditions of about room temperature.
Seeds treated with a warm / warm / wet layer are sown in the nursery, and the nursery is repeatedly subjected to light-dark treatment under high-temperature / light conditions and low-temperature / dark conditions until rooting.
The rooted seeds are treated with a cold / hot wet layer under constant temperature and dark conditions at a low temperature of about the winter temperature.
A method for promoting germination, which comprises culturing seeds treated with a cold / hot and wet layer at a temperature of about spring to early summer to germinate them.
2. 2. The refractory plant is characterized by being a plant with epicotyl dormancy. The germination promotion method described.
3. 3. The soil containing humus is characterized by being mainly Andosols or red soil. Or 2. The germination promotion method described.
4. A method for promoting germination, which comprises promoting the germination of seeds of a difficult-to-germinate plant by the following steps.
First step: A step of drying the seeds from which the pulp has been removed from the collected fruits and storing them at a low temperature.
Second step: The stored seeds are buried in Andosols containing wet humus or red soil containing humus and sealed.
Third step: The sealed seeds are treated with a warm and warm wet layer at a constant temperature of 20 to 25 ° C. for 5 to 15 days under dark conditions.
Fourth step: After the warm / warm wet layer treatment, the seeds are taken out from Andosols or red soil, washed with water, and sown in the nursery as it is or after sterilization.
Fifth step: The seeded nursery is repeatedly cultured and rooted under high temperature (20 ° C. or higher) / light conditions and low temperature (20 ° C. or lower) dark conditions.
Sixth step: The seedbed of rooted seeds is treated with a cold / hot and wet layer for about one month under low temperature (0 to 10 ° C), high humidity and dark conditions.
Seventh step: The nursery bed treated with a cold / hot and wet layer is cultured under the temperature conditions of early summer to germinate.
5.1. ~ 4. A method for cultivating a difficult-to-germinate plant, which comprises transplanting seedlings germinated by any of the germination promoting methods described in the above into planting soil, raising seedlings, and cultivating the seedlings.

1. 1. By applying the present invention to gadgets, Styrax japonicum, Styrax japonicum, Anemone nikoensis, etc., which are considered to be difficult to germinate with epicotyl dormancy, the period required for germination and the period for raising seedlings can be shortened. Without treatment, a germination period of one and a half years or more is usually required, but in the present invention, the germination period can be halved to about 200 days.
2. 2. By applying the present invention to viburnum, Styrax japonicum, Styrax japonicum, Anemone nikoensis, etc., which are considered to be difficult to germinate, the germination rate is increased and the yield of seedling production is improved.
3. 3. By applying the present invention to seeds that have been dried and refrigerated after collection, germination can be induced at any time and seedling production can be started, so that the seedling supply can be stabilized.
4. When it is required to use native tree species and herbs for greening, seedlings can be grown in a short period of time from the seeds of native plants growing in the planned site and applied. In addition, when restoring natural vegetation over a large area, it is possible to carry out spray greening work using the seeds of the native plant treated by the present invention to promote germination, and to establish them at an early stage.
5. When conducting redevelopment projects in urban areas, there are many cases of greening using native plants for the purpose of preserving biodiversity in consideration of the surrounding natural environment. Saplings of native plants commonly used for greening are produced using seeds collected from trees that grow naturally by producers. However, native species include tree species and wildflowers, such as viburnum and Styrax japonicum, which have a low germination rate and take a long time to germinate after sowing. Therefore, it is difficult to constantly procure such plants, and it is possible to establish a system that can stably supply even plants that are difficult to germinate.

The figure which shows the seed which is dried and stored after collection. The figure which shows the preparation state of a warm-warm wet layer treatment. The figure which shows the state which sown in a petri dish. The figure which shows the rooting state. The figure which shows the germination state. The figure which shows the germination state. The figure which shows the rooting and germination state of the seed of Styrax japonicus. (A) Rooting state and (b) Germination state are shown. Diagram showing viburnum flowers and seeds. Diagram showing flowers and seeds of Styrax japonicus.

The present invention is a method for promoting germination of hard-to-germinate tree species such as Styrax japonicum and Styrax japonicum with epicotyl dormancy and seeds of wild grass.
The present invention mainly promotes germination by performing the following treatments.
Among plants, there are difficult-to-germinate plant species having the property of morphological and physiological dormancy in which seeds ripen while embryos are immature and embryo development and seed germination do not proceed unless temperature conditions are adjusted. In addition, plant species with morphological and physiological dormancy are divided into nine groups according to the temperature conditions leading to embryo development and rooting / germination. Among them, the temperature conditions that promote embryo development and the temperature that induces germination. Plants with epicotyl dormancy under different conditions are one of the groups that take longer to germinate.
The present invention is a method for germinating difficult-to-germinate seeds at any time in a short period of time against turtles, egonoki, katakuri, and anemone nikoensis, which are often used for greening among plant species having epicotyl dormancy. Is to provide. The present invention mainly promotes germination by performing the following treatments.
1. 1. Before sowing seeds stored at low temperature, the soil containing humus such as Andosols and red soil is used as a water-retaining material and heated under room temperature conditions (hereinafter referred to as "warm and warm wet layer treatment"). To do.
2. 2. Seeds treated with a warm / warm / wet layer are sown in the nursery, and the nursery is repeatedly subjected to light-dark treatment under high-temperature / light conditions and low-temperature / dark conditions until rooting.
3. 3. The rooted seeds should be treated with a cold / hot wet layer at a low temperature of about the winter temperature under high humidity and dark conditions.
4. Perform germination treatment by culturing the nursery bed treated with a cold / warm wet layer at a temperature of about spring to early summer to germinate.

Seeds of viburnum, Styrax japonicum, Erythronium japonicum, and Anemone nikoensis are not always sold, so they should be collected at the time when seeds are formed, the pulp should be removed, dried, and stored at a low temperature of about 0 to 7 ° C.
The stored seeds are treated with a warm / warm wet layer before sowing. The warm / warm / wet layer treatment is carried out in a moist state and kept at room temperature of about 20 to 25 ° C. for 5 days or more (about 5 days to 1 month) under dark conditions. A period of 1-2 weeks is sufficient. The temperature can be controlled using a constant temperature room. Use water-retaining materials to keep it moist. Cultivated soil or cotton is used as the water-retaining material, and it is stored in a container that can be sealed so that it will not dry out. As a water-retaining material, the treatment effect was confirmed with moistened cotton wool and sand, but in order to shorten the period until rooting, Andosols and red soil containing corrosive components are suitable. For Andosols, use soil that is weakly acidic and contains humus. The water-retaining material may be sterilized.

The seeds treated with the warm / warm / wet layer are then taken out from the water-retaining material, washed with water to remove the water-retaining material, and further subjected to sterilization treatment as necessary to sow in the nursery. For the nursery, use ordinary seedling raising materials such as sowing boxes and pots.
As the soil for the nursery, ordinary planting soil such as Akadama soil can be used. In addition to Akadama soil, sand, Andosols, peat moss, etc. can be mixed and adjusted as the planting soil. Common green soils such as prepared artificial lightweight soils can also be used.
Diluted benlate can be used as a disinfectant for sterilization.
The seedbed is repeatedly subjected to light-dark treatment under high-temperature / light conditions and low-temperature / dark conditions until rooting.
The light / dark condition is basically a 24-hour cycle, and is generally set to 12 hours for the bright condition and 12 hours for the dark condition, but it is also possible to make the time of the bright condition longer than that of the dark condition.
Under bright conditions, the temperature is about 20 to 30 ° C. Under dark conditions, the temperature is about 10 to 20 ° C. The temperature difference is set to about 5 to 15 ° C, preferably about 10 ° C.
Since the light / dark processing provides an environment in which temperature control and lighting control can be performed, the set temperature is set to a high temperature of 25 ° C., a low temperature of 15 ° C., a 12-hour cycle, or the like.
The period until rooting is affected by the warm / warm and wet layer treatment conditions and the light / dark treatment conditions, so it cannot be said unconditionally, but in the examples using viburnum, it was 3 to 4 months. After rooting, continue culturing under the same conditions for another month as the root growth period.

The rooted seeds (nursery) are treated with a cold / hot wet layer at a low temperature of about the winter temperature under high humidity and dark conditions.
If the nursery is small, the rooted seeds are transferred to a planting container (such as a seedling pot) filled with soil for cultivation and treated with a cold / hot wet layer.
The temperature is about 0 to 10 ° C, centered on 5 ° C. Further, 0 to 5 ° C. is suitable. Water the soil so that it does not dry out and keep it sufficiently humid. The low temperature and high humidity conditions are cultivated for about one month under dark conditions. If it is necessary to control the temperature, use a constant temperature room and set it to about 5 ° C.

After treatment with a cold / warm wet layer, the nursery is cultured at an appropriate temperature for germination from spring to early summer to perform germination treatment.
The temperature is about 15 to 25 ° C. When cultivated with appropriate water supply, it germinates in about one month. Continue raising seedlings after germination to grow seedlings.
By performing the above germination treatment, it is possible to shorten the time from the start of the warm / warm wet layer treatment to germination to about 200 days.

As the soil used in the present invention, ordinary cultivated soil can be used.
Basic soils for cultivation include Andosols (Kurosoil), Akadama soils, Kanuma soils, Hinata soils, Arakida soils, Keto soils, river sands, Fuji sands, Kiryu sands, and water moss. These include humus, compost, smoked charcoal, vermiculite, perlite, peat moss, zeolites, silicate clay, pumice and the like.
Moisturizing sphagnum moss and sand can be used as materials for warm and warm wet layer treatment, but humus soil and weakly acidic Andosols were found to be suitable. In addition, germination could be confirmed even in red soil containing humus.
Andosols are black volcanic ash soils, also known as black soils, which are fluffy and are often used as soil for fields. The soil is made of volcanic ash and dead plants, and the fertilizer component of the soil itself is low. It has good water retention and fertilizer retention, but poor breathability and drainage, and is weakly acidic. The soil becomes fluffy and suitable for root vegetable cultivation. In addition, because it has the property of adsorbing phosphoric acid, it is not suitable for plants that bear flowers and fruits and consume a large amount of phosphoric acid.
As the planting soil after the warm and warm wet layer treatment of constant temperature and room temperature with Andosols and red soil, ordinary cultivated soil can be used. For example, humus soil centered on Akadama soil, peat moss, andosols, etc. are mixed and adjusted.

<Regarding the germination process of viburnum>
Viburnum is a deciduous shrub that belongs to the genus Viburnum of the honeysuckle family and grows naturally in sunny mountains and forest edges, and is a native plant used as a greening material. Inflorescences are borne around May and June, and many white flowers are borne. It bears fruits in autumn and turns red in early winter, but it has a strong acidity. The fruit is a drupe, with a thin flesh and one large seed. The leaves turn red in late autumn, and after the leaves have fallen, red fruits stand out. It is also used for fruit wine. The flowers and fruits of viburnum are shown in FIG.
There is one seed covered with thin flesh in the fruit, but it is generally desirable to collect it in late autumn when the flesh begins to rot. After soaking the collected fruits in water for several days to remove the peel and pulp from the seeds, the seeds are left to dry in a well-ventilated room for several days in order to maintain the germination vigor without spoiling the seeds. In this process, viburnum seeds go dormant. Dried seeds can be placed in a sealable storage bag such as Ziplock® and stored in a refrigerator set at 0-5 ° C for a long period of time.

To germinate the stored viburnum seeds, put Andosols in a newly prepared storage bag, bury the seeds in it, and close the seal. At this time, it is desirable that the soil to be put in the storage bag is moist enough to allow water to seep out when grasped by hand. Next, the seeds are placed in an incubator set at 20 to 25 ° C. under dark conditions together with the storage bag, and the seeds are treated with a warm and warm wet layer for about 5 to 15 days (1 or 2 weeks). It is sufficient to heat for about 1 week to promote germination, but it is desirable to extend the treatment period to about 2 weeks.

After the treatment, the seeds are taken out from the Andosols, washed with water, and then sown in a nursery lined with planting soil such as Akadama soil. The soil used at this time is not limited to Akadama soil, but general greening soil such as sand, Andosols, and artificial lightweight soil containing soil conditioners such as peat moss may be used. Further, the seeds may be immersed in Benlate (a fungicide) diluted about 700 times to sterilize molds and the like on the seed surface. Further, when sowing, it is desirable to cover the soil with a thickness of about 5 to 10 mm so that the seeds do not float on the surface of the nursery.
Then, the nursery in which the seeds are sown is transferred to an incubator set to light conditions: 12 hours (25 ° C.) and dark conditions: 12 hours (15 ° C.), and the seeds are cultured. During the culture period, water should be supplied appropriately so that the nursery is always moist. Also, from time to time, dig up the seeds to see if they are rooted.

When viburnum seeds are wrapped in Andosols, treated with a warm and warm wet layer, and then sown in a nursery, rooting usually begins in about 100 days, but in order to fully grow the roots, it takes about one month after rooting. Continue culturing under the same conditions. After the roots have grown sufficiently, the nursery is transferred to an incubator and treated with a cold / hot wet layer at 0 to 5 ° C. under dark conditions for about one month. After that, if the nursery is moved to a greenhouse set to a temperature condition suitable for germination (15 to 25 ° C.) or outdoors and water is appropriately supplied, germination will occur in about one month.
By culturing viburnum seeds wrapped in Andosols and treated with warm and warm wet layers in the above process, it is possible to shorten the period from the start of treatment to germination to about 200 days. became.

<Regarding the germination process of Styrax japonicus>
Styrax is a deciduous tree belonging to the genus Styrax in the family Styracaceae. The trunk is not thick and is often found in bright forests. In early summer, neat white flowers bloom all over the branches, so the thickets during the rainy season become brighter for a while. The fruits are oval-shaped drupes and grayish white. When it ripens around October, the pericarp tears and the seeds fall. Since the pericarp contains a lot of egosaponin, it can be used as a substitute for soap, or because it is toxic to fish, it is said to have been ground and used for poisonous fishing. Varied tit is said to prefer seeds. The flowers and fruits of Styrax japonicum are shown in FIG.
Germination of Styrax japonicum seeds could be promoted by treating them in the same manner as Viburnum dilatatum.

In order to verify the effect of the present invention, a germination test was conducted using seeds collected in December from viburnum dilatatum growing in natural forests in Yokohama city.

The collected fruits were taken back to the laboratory and left in a bucket of water for about 3 days. The seeds were stripped from the soaked peels and fruits because they were soaked in water, spread on newspaper, and left indoors until they were dry. After drying, the seeds were placed in a bag, the seal was closed, and the seeds were stored in a refrigerator set at 0 to 5 ° C. until a germination test was conducted. The seeds of viburnum in storage are shown in FIG.

A germination test was conducted from November of the following year.
Before conducting the germination test, in order to confirm whether the germination rate decreased during the storage period, the germination rate was examined by the early germination ability test method outsourced to an external testing institution. As a result, the germination rate of viburnum seeds collected in December of the previous year was about 30%, which was not significantly different from the germination rate of viburnum seeds reported in previous studies. The early germination ability test method for woody plant seeds is introduced in Nichiryoku Kogyo 30 (1), pp. 261 to 264. It is also disclosed in Japanese Patent No. 3527210.

In verifying the effect of the present invention, 15 test categories were set as shown in Table 1.
As 12 test plots, the following 1. ~ 3. Test plots (test plots 1 to 12) subjected to the above treatment.
The following 4. 2 test plots (test plots 13 and 14) for which the above treatment is performed, the following 5. 1 test plot as an untreated control plot (test plot 15).
1. 1. Two types of media for wrapping seeds: Andosols, water The water medium is a state in which seeds are placed in an experimental tube (bin) of about 15 ml, water is added to it, and the water is soaked in water.
2. 2. Treatment temperature 3 Conditions: 15 ° C, 20 ° C, 25 ° C
3. 3. Treatment period 2 Conditions: 1 week, 2 weeks 4. 2. Warm at 20 ° C for 2 weeks using sand and sterilized Andosols. Untreated control group: Light and dark treatment is performed without heating treatment (warm and warm wet layer treatment).

Put different media for each test group in a bag, bury 30 viburnum seeds stored in the refrigerator, and set the temperature (15 ° C, 20 ° C, 25 ° C) and period (1 week, 1 week) for each test group. The warm and warm wet layer treatment was performed according to (2 weeks).
As for the Andosols to be put in the bag, the sterilized Andosols, and the sand, water was used so that the water content was the same. FIG. 2 shows a state in which processing is performed.

After the warm and warm wet layer treatment was completed, the seeds taken out from each test group were washed with water, a wet filter paper was laid on a petri dish having a diameter of 9 cm, and 10 seeds per test group were placed in 3 dishes. The petri dishes were placed in a small seedling raising device set under light conditions (12 hours, 25 ° C.) and dark conditions (12 hours, 15 ° C.), and the seeds were cultured. See Figure 3.
By observing regularly, the date when rooting was first observed in each petri dish was recorded, and the number of rooting in each petri dish was measured 4 months after the start of culturing with the seedling raising device. The results are shown in Table 1. The rooting state is shown in FIG. Rooting was done first and the buds have not grown yet.
In the test, 10 seeds were sown in 3 dishes in 1 test area, and the number of roots was measured 4 months after the date when rooting was first confirmed in each dish, and the average value of the 3 dishes was measured. Is converted into data and shown. Therefore, even if rooting is confirmed on one or two petri dishes after 4 months, if rooting is observed on the other petri dish after 120 days, it takes on average to take rooting. The number of days may exceed 120 days.
The number of roots in the test group 15 after 120 days was 0.

When the number of days from the start of culture to the confirmation of rooting was averaged for each test group, a significant difference was observed in the test section.
In the untreated plot (test plot 15), it took 150 days to root, whereas in the test plot in which the seeds were wrapped in Andosols and treated at 25 ° C for 2 weeks, it took 96.3 days. there were.
In addition, there was a difference in the number of days required for rooting depending on the medium that wraps the seeds. It took an average of 112.9 days for rooting in the 6 test plots in which the seeds were wrapped in andosols and heated, but it took 128.6 days in the 6 test plots in which the seeds were heated in water.
In the test plot where the seeds were wrapped in sand and heated at 20 ° C for 2 weeks, it took 139.0 days, whereas in the test plot using sterilized Andosols, the number of days required for rooting was 109. It was almost the same as the test plot using unsterilized Andosols.

Table 1 shows the results of measuring the number of roots in each test group 4 months after the start of culturing.
Similar to the number of days required for rooting, there was a significant difference in the number of rooting in the test section.
The largest number of roots was in the test plot where the seeds were wrapped in Andosols and heated at 25 ° C for 2 weeks, with 4.0 roots per chalet and the number of roots in the untreated plot (0 seeds). ) Was significantly higher.
In addition, the number of roots in the 6 test plots using Andosols was significantly higher than that in the 6 test plots using water as a medium.

From the above results, it was clarified that by wrapping viburnum seeds in soil and heating them at a temperature of 15 ° C or higher for about one week, the period until rooting is shortened and the number of seeds to be rooted increases. rice field.
Since rooting could be promoted even with sterilized Andosols, it was considered that some compound, not the microorganisms contained in the soil, affected the rooting.
In addition, after transplanting the rooted seeds to the planting soil and treating them with cold temperature for one month, they were transferred to a greenhouse to check the germination status. No influence was observed on the wrapping medium, heating temperature, or period. The germination state is shown in FIGS. 5 and 6.

For the Egonoki seeds stored in the refrigerator, bury the seeds in Andosols packed in a bag, treat them in a warm and humid layer at 20 ° C for 2 weeks in a dark place, and then put them in a pot filled with planting soil. The seeds were transplanted and cultured in a small seedling raising device set to light conditions: 12 hours and 25 ° C., dark conditions: 12 hours and 15 ° C., and rooting was achieved in about 120 days. In addition, the rooted seeds were subjected to cold treatment for one month and then transferred to a greenhouse, where they were able to germinate.

Claims (5)

Seeds of plants that are difficult to germinate,
A warm and warm wet layer treatment using soil containing humus as a medium is performed under constant temperature conditions of about room temperature.
Seeds treated with a warm / warm / wet layer are sown in the nursery, and the nursery is repeatedly subjected to light-dark treatment under high-temperature / light conditions and low-temperature / dark conditions until rooting.
The rooted seeds are treated with a cold / hot wet layer under constant temperature and dark conditions at a low temperature of about the winter temperature.
A method for promoting germination, which comprises culturing seeds treated with a cold / hot and wet layer at a temperature of about spring to early summer to germinate them. The method for promoting germination according to claim 1, wherein the difficult-to-germinate plant is a plant having epicotyl dormancy. The germination promoting method according to claim 1 or 2, wherein the soil containing humus is mainly Andosols or red soil. A method for promoting germination, which comprises promoting the germination of seeds of a difficult-to-germinate plant by the following steps.
First step: A step of drying the seeds from which the pulp has been removed from the collected fruits and storing them at a low temperature.
Second step: The stored seeds are buried in Andosols containing wet humus or red soil containing humus and sealed.
Third step: The sealed seeds are treated with a warm and warm wet layer at a constant temperature of 20 to 25 ° C. for 5 to 15 days under dark conditions.
Fourth step: After the warm / warm wet layer treatment, the seeds are taken out from Andosols or red soil, washed with water, and sown in the nursery as it is or after sterilization.
Fifth step: The seeded nursery is repeatedly cultured and rooted under high temperature (20 ° C. or higher) / light conditions and low temperature (20 ° C. or lower) dark conditions.
Sixth step: The seedbed of rooted seeds is treated with a cold / hot and wet layer for about one month under low temperature (0 to 10 ° C), high humidity and dark conditions.
Seventh step: The nursery bed treated with a cold / hot and wet layer is cultured under the temperature conditions of early summer to germinate. A method for cultivating a resistant plant, which comprises transplanting seedlings germinated by any of the germination promoting methods according to claims 1 to 4 into planting soil, raising seedlings, and cultivating the seedlings.

Images