Botany is an imprecise science. I was convinced of this more than once on my own experience. With Dioscorea of Nipponskaya, for example, this is the incident. All clever books claim that this herbaceous vine is a dioecious plant. Dioecious means heterosexual. There are male plants and there are female plants. One can grow without the other, but it cannot give seeds.
Note that at one time I received a single root from the Far East. Male or female - it was not clear. In general, there was nothing to count on getting seeds. For two decades, everything has been so. But in its third decade, the liana tied fruits, inside of which something like flat seeds, like small coins of seeds, could be traced. Not believing my eyes, and deeply doubting the success, I still sowed them. Fortunately, winter 2012/2013 was extremely favorable for wintering plants. The frosts are moderate, there is a lot of snow.
And now it’s spring, I’m waiting for the shoots, but they are in no hurry. May has passed, June has crossed the equator - there are no shoots, just like not. And suddenly, one fine morning, almost on the day of the summer solstice, I dreamed that some sprouts were making their way to the surface of the soil. I look, and for sure - in front of me are dozens of tiny, but already well-recognizable leaves. There is no doubt - this is Dioscorea! How much!
But how can this be? After all, I have only one plant.
Nippon riddle
Immediately, I note that Dioscorea is an extraordinary plant, like the Greco-Roman doctor Dioscorides, by whose name it is named. Everything in it speaks of a foreign origin. The leaves, although they cannot be called exotic, are unusual for central Russia. An experienced glance will notice the parallel venation, which is rare in our plants, but so characteristic of the entire family of Dioscoreae. The leaf shape is also typical and recognizable. And if you dig the soil, you will find a rather short tuberous thickened rhizome, also very characteristic of Dioscoreae.
Dioscorea has been present in our garden since about 1989-1990, and all this time it has been growing in one place. The site was chosen in accordance with the recommendations that were available in the literature - semi-shady, with permeable, humus-rich soil.
Liana took root without any problems, but was in no hurry to grow. At first, it developed without support, but then it found it in the person of actinidia growing nearby, and began to climb its lashes every year. At first, not higher than a meter, but with age, to a height of about 2.5 m. The fact that Dioscorea was developing could be judged by the number of shoots. At first it was only one, then, when the rhizome spread 70 cm in width, there were more than a dozen of them. By the way, they are very thin, with a match, grow in one thread, practically without branching, and winding around the supports clockwise.
From 10-12 years old, the liana began to bloom. Nondescript, greenish in color, and very small flowers, as one would expect, fell off without setting the fruit. This continued until the age of 17-18, from which the fruits appeared - three-lobed capsules. But they didn't ripen. From year to year, the boxes became larger, but as soon as they were opened, it was clear that nothing was tied inside. This continued until 2012, when the fruits reached unusually large - about 2 cm in length and size. And as already mentioned, they set up viable seeds.
But botanists, and this is not difficult to verify, (Life of Plants, Volume 6, p. 232) consider the vine to be dioecious. And where, one wonders, has gone to her dioeciousness ?! And was it even at all, maybe this plant is still monoecious? And if this plant was originally female, how was it fertilized? In general, here's to you, associate professors with candidates, a question to fill in: what happened?
Personally, I have two versions of the explanation for what happened. First, dioscorea is a polymorphic species, and can be both monoecious and dioecious. Second, in the absence of a pair, dioecious dioscorea can be reborn into monoecious, but this happens only at a sufficiently mature age of the vine. This phenomenon, by the way, is not uncommon. Also, for example, dioecious Arizems behave.
I myself, too, did not sit idly by and, armed with a 10x magnifying glass, undertook my own investigation. It was found that the flower (corolla) of my dioscorea has six microscoric petals, opposite each of them a stamen sticks out, and in the center there is one pistil. It turns out that this liana, after all, has a normal sexual orientation, or, more simply, is monoecious, like most flowering plants on earth?
After rummaging through the literature and thinking it over, I'm still more inclined towards the second version. And this is how it appears to me in its final form: - My Dioscorea was originally male. (It is known that in nature male plants are found much more often than female ones.) The structure of its inflorescence also indicates that the male plant is also racemose and rather long, while in female plants, according to descriptions, it should be compact. The flower of the male Dioscorea Nippon, in addition to the six stamens, has an underdeveloped pistil, or gynoecium. So, my Dioscorea's gynoecium developed into a full-fledged pistil with age, and she got the opportunity to fertilize and give ripe seeds.
So you know.
The genus Dioscorea of the Dioscorea family of the same name, according to botanists, contains more than 500 species. Dioscorea are very ancient plants, mainly tropical and mainly Asian. The center of their origin is somewhere in Indochina. Dioscorea are found on all continents, except, of course, Antarctica. But in America, Australia and Africa, they are relatively few in number. The northernmost representatives of the genus are three types of Dioscorea, which are found in the Russian Far East.
Almost all Dioscoreas are herbaceous plants, most often liana-like, although there are also shrubs. Dioeciousness is a mandatory sign of the genus.
Despite the abundance of species, Dioscorea are quite recognizable. To identify the genus, it is usually sufficient to look at the leaves of the plant. A typical leaf of Dioscorea is simple or weakly lobed, heart-shaped with a pointed tip. The leaf has a well-recognizable arcuate venation, with 3-9 primary veins and a dense network of small veins between them.
On vines, the leaves grow with their points straight down and, as it is believed, all together form an ordered mosaic, directing atmospheric precipitation to the area of occurrence of the rhizome. This, according to biologists, is a kind of adaptation to self-irrigation, because the roots of the dioscorea lie in the surface layer of the soil, which is rapidly losing moisture, and have few adventitious roots.
Compact, often tuberous, storage-type roots are also very characteristic of the genus. Sometimes they look like thick, fleshy rhizomes, similar to those of the kupena, and sometimes they resemble potato tubers. An example is several types of dioscorea with large edible tubers - yams, which have been cultivated since ancient times in the tropics of Africa and Asia.
And, finally, an interesting feature of the Dioscorea genus is the conspicuous discrepancy between the thickness of the shoots of the vines - often literally filamentous, rather large sizes of rhizomes and tubers.
Dioscorea Nippon (aka Japanese) (D. nipponica)- the only non-Red Book species of Dioscorea from the Russian flora. In Russia, the range of this herbaceous dioecious liana is the Primorsky Territory and the south of the Khabarovsk Territory, where it grows along the edges of deciduous forests and in tree-shrub copses.
The fruits of Dioscorea Nipponskaya have the appearance of three-winged capsules, with flat pterygoid seeds hidden in the valves, similar to the fruits of the elm and yarrot.
Dioscorea Nippon can be grown practically throughout the entire European part of Russia, but not to the north of the mixed forest zone. There is information that in the conditions of the Moscow region it is possible to cultivate other types of dioscorea, for example, the deltoid (D .deltoidea) - native to the Himalayan highlands of India.
Agrotechnics
Dioscorea nipponskaya is not a difficult plant in agricultural technology, but it has rather pronounced preferences. At the same time, it will also tolerate significant deviations from a favorable agricultural background. Only boggy or excessively lean and at the same time dry soil can lead to the death of a vine.
Dioscorea is shade-tolerant and drought-resistant enough. For example, the plant survived the catastrophic drought of summer 2010 without any noticeable changes in its appearance. And yet, the plant develops better on humus-rich, well-drained, and at the same time constantly moist soils.
Landing place. The location of the dioscorea rhizome should be in the shade or mesh penumbra, and the liana itself, that is, its leaves and fruits, in the sun. A completely open location, like a thick shade, although portable, is unfavorable.
The soil. The substrate should maximally combine fertility and permeability. It is easy to prepare it on the basis of turf, peat and sand, mixing in an approximate ratio of 1: 2: 2 or 1: 2: 1. The thickness of the cultivated layer is 10-15 cm.
Care. Fertilizer. Due to the roots close to the soil surface, it is impossible to dig up the foot of the vine. It is undesirable even to loosen. Weeds practically do not grow at the foot of the liana. All care comes down to fertilization, which is advisable to apply in the form of mulch. This can be done continuously, but in small doses, as it is assimilated by the soil. Well-rotted plant residues are especially useful as mulch: leaf humus of forest tree species (aspen, birch, maple, linden, etc.), high-moor peat, compost from rotted weeds.
Watering. Dioscorea takes root better and grows faster with sufficient and constant soil moisture. In the absence of precipitation, and especially in extreme heat, it is advisable to water it at least once a week. It is better to do this by sprinkling, with irrigation of the leaves.
Reproduction. The most effective way is seed, which has already been mentioned. Dioscorea blooms in our garden in mid-June. The cuttings reach their maximum size only in September. But practically until frost they remain green. Therefore, I cut off the fruits as late as possible. I do not extract the seeds from the boxes, I sow the boxes themselves, just as they are, sprinkling them with a layer of high peat about one centimeter. As it turned out, this method of sowing is effective. I give seedlings to grow at the sowing site for two to three years, after which they can be transplanted immediately to a permanent place.
Dioscorea can also be grafted. To do this, in mid-June, I cut the lianas and cut their ripe part into cuttings with two internodes. But, this method is less effective than seed.
Decorative and medicinal
Despite the lack of bright colors, Dioscorea is very decorative with its original leaves and the ordered mosaics that they form. It is very durable and obviously rivals our forest tree species in this. The slow growth of vines in the eyes of an experienced gardener is rather an advantage. After all, having reached maturity, a plant can grow for decades in one place practically maintenance-free, and within the same framework.
In landscaping, it makes sense to use dioscorea to decorate the walls of houses, gazebos, outbuildings. In this case, it is planted where the precipitation flows, and then the issue of watering by itself disappears.
In addition to decorativeness, its medicinal properties are highly valued in Dioscorea. It has a diuretic effect and lowers blood pressure. But its main indication is considered to be anti-sclerotic. It was found that dioscorea lowers blood cholesterol levels. By the way, you can take dioscorea preparations for a long time, since there are no negative side effects for it.
Dioscorea's medicinal raw materials are rhizomes. They can be harvested during the entire gardening season from April to late autumn. The dug roots are washed with water and dried under an iron roof or in an electrical cabinet, at temperatures up to 60-70 o C. Raw materials are considered suitable for up to three years.
This spectacular vine, belonging to the Dioskorei family, is interesting not only for its decorative properties. It is a medicinal plant and is valued as an agricultural crop.
Origin of the name
The plant is named after the Greek naturalist and physician Dioskoreus. Along with the official one, there are other, no less common, names. For example, yams or wild yams.
Where is found
The genus unites plants of the subtropics and tropics, and only a few of them grow in warm temperate zones. Today Dioscorea is rare, and therefore a protected plant, listed in the Red Book.
Application
Dioscorea has medicinal properties and is widely used in pharmacology. The greatest therapeutic effect is possessed by preparations prepared from the rhizomes of vines that have reached 25 years of age. Decoctions and infusions made from tubers have a powerful tonic, immunostimulating, urine and choleretic, calming effect.
The inhabitants of Africa and Asia have long been using the fleshy tubers of vines for food. In these regions, some types of Dioscorea grown asvaluable agricultural crop .
Many types of plants are decorative and are cultivated both outdoors and indoors.
Description
Dioscorea is a perennial vine that grows in length by several (from 2 to 12) meters. Most of the species have herbaceous shoots, but woody forms are also found.
All of them are united by a spectacular appearance: vines cover the ground with a thick carpet or rush up the support.
Vine shoots are covered with whole, petiolate, different shades of green, lobed or articulated, with a heart-shaped base leaves. They differ in shape and location on the shoot:
- in the upper third of the stem, the leaf blades are pointed and opposite;
- at the bottom - cordate or oval, whorled.
The underground part of the vines is a rhizome consisting of one or more fleshy tubers.
Dioscorea blooms in spring. However, this event is of little note. The buds are small and inconspicuous. The flowers are single or collected in small-sized inflorescences of various shapes: an ear, a brush or a half-umbel.
The corolla of the flowers consists of 6 petals, painted in greenish-yellow tones
Views
The genus includes about 600 plant species. In the gardens and premises, they grow those of them that we managed to acquire.
Dioscorea Caucasian
Occurs in the Krasnodar Territory (Adler District) and Abkhazia, on rocky soils, preferring mountain slopes and thickets of wormwood and bushes. It is an endemic listed in the Red Book. In order to restore its numbers, the species is cultivated.
Dioscorea opposite
It is distinguished by:
- long, up to 10 m, twisted or angular shoots;
- nodules located in the leaf axils;
- light flowers, collected in racemose inflorescences and having a pleasant smell, similar to that of cinnamon.
The roots and leaves of this vine are used for medicinal purposes.
Dioscorea of Nippon
It grows in East Asia and the Primorsky Territory, in China and Japan and is characterized by:
- thick horizontally located rhizome;
- long (up to 4 m) naked shoots with alternately located cordate or lobed leaves.
Dioscorea elephant
This species grows in South Africa and is rightfully considered exotic. Its uniqueness lies in the presence of a ground caudex, which has a spherical shape and is covered with cork growths in the shape of polygons.
From the top of the caudex, long curly shoots grow, bearing heart-shaped leaves with rounded lobes
The thickening is often impressive in size, growing to a record gigantic size: 3 m in height with 1 m in diameter and a weight of 400 kg.
Caudex pulp contains a large amount of starch. It is edible and tastes like a turnip.
This species is not used for medicinal purposes, but is valued as an exotic ornamental plant.
Dioscorea batatas (sweet potato)
This vine is distinguished by creeping pubescent shoots, stretching up to one and a half meters. They are decorated with bright glossy green leaves and blue flowers that develop in the axils of the leaves.
Growing
Lighting requirements and location
Dioscorea is photophilous, but prefers diffused light rather than direct sunlight, which can cause leaf burns. It grows slowly in the shade. The best place for the location of the creeper will be the western side of the site or room.
Air temperature
Dioscorea is not only light, but also thermophilic. In summer, lianas are comfortable at temperatures above 25 ° C. In winter, she prefers coolness - no more than 10 ° C.
When grown in open ground for the winter, Dioscorea is covered, after mulching the soil with fallen leaves.
Air humidity and watering
The humidity of the air is not significant for the plant, but the liana is demanding of the state of the soil. It must be constantly hydrated. This can only be achieved by frequent and not abundant watering.
The soil
Dioscorea thrives on light, nutritious, organic soils. When grown indoors, you should give preference to a mixture consisting of equal parts of humus, sand, heather earth and pine bark.
Top dressing
In spring and summer, once every two weeks, the plant is fed with a universal liquid organic fertilizer.
Dormant period
In the fall, having shortened too long shoots, the tubers of the vines are removed from the ground and sent to storage in a dark and cool place. In the spring they are re-planted. Indoor plants can also be sent to rest, right in the pot.
Transfer
Once a year, in the spring, on the eve of the active growing season, Dioscorea needs to be transplanted, making a complete replacement of the soil. At the same time, it is not necessary to change the capacity: the roots of this plant develop better in cramped conditions.
Reproduction
Dioscorea can be propagated vegetatively: by dividing the rhizome or by shoots.
- It is convenient to divide the rhizome during plant transplantation, placing each resulting area in a container corresponding to its size.
- In the spring, you can separate the shoots from the tubers. They will be rooted in water and then planted in open ground or pots.
Dioscorea also propagates by seeds. This method is more laborious, including the purchase of seed:
- Soil: Any universal composition of earth mixed with perlite will do.
- Seeds are placed on the surface of the soil, deepening by 1 cm.
- Greenhouse conditions are created for crops: 25 ° C heat with periodic slight soil moisture. After 3 weeks, the first shoots will appear. They will be provided with a backlight, otherwise the seedlings will become excessively stretched.
- Fortified young vines are planted in separate pots.
Diseases and pests
Dioscorea is disease resistant. Of the pests, liana is threatened only by the spider mite, which develops in very dry air.
Dioscorea is able to decorate any plant collection. As a long-liver, she will delight you for decades.
Enlarge text
Dioscorea Caucasian - perennial dioecious herb - liana. The stem of the dioscorea is thin, it develops up to 4 meters in height, needs support. The roots are directed horizontally, thick with many dormant buds. The aboveground part dies off for the winter. Dioscorea leaves are heart-shaped, green in color, arranged alternately. The flowers are small, collected in inflorescences-clusters of yellow color. The plant is resistant to low temperatures - tolerates up to -25 С, is rarely damaged by diseases and insects. Dioscorea Caucasian is an endangered species, so you can rarely meet it. Every year, the rhizome of Dioscorea grows by only 2-3 cm, so it slowly spreads into nature.
Planting conditions for Caucasian Dioscorea
It is necessary to plant dioscorea in neutral soil, if the acidity is increased, lime must be added. Also, the soil should contain humus and good drainage, it needs regular watering. It prefers to grow in a semi-shaded area where there is no strong blowing wind. Direct sunlight negatively affects the flower, and because of the full shade, the dioscorea will develop poorly. Before planting, the site should be cleaned of perennial rhizomes and weeds. When choosing a place for planting, it must be borne in mind that a young Dioscorea first needs protection for the winter, because may die due to frost. It is not recommended to dig up the soil, because the roots of the plant are close to the surface. Loosening is also not recommended.
Reproduction of Caucasian dioscorea by cuttings
This method is most often used for reproduction of Dioscorea. To do this, in the spring, it is necessary to cut the upper cuttings and place them in the peat soil, adding perlite. You can also root in sand with soil. Next, the planting must be covered with plastic wrap to create a greenhouse. Cuttings should germinate in diffused lighting in a warm room. Sometimes you need to air the planting and water a little. When the cuttings become stronger, you can grow a little more, and then transplant to a permanent place.
Reproduction of Caucasian dioscorea by dividing the bush
The strips should be cut into a length of about 15 cm and planted in the autumn, when the growing season is over.
Reproduction of Caucasian dioscorea seeds
Reproduction of dioscorea by seeds is a rather problematic and time-consuming process. You can sow outdoors or in indoor pots. For indoor cultivation, sowing seeds is carried out in April in sand mixed with leafy soil. It is recommended to germinate at 15 ° C and, if necessary, water it. When the seedlings sprout, they are kept in diffused light or in partial shade. Later, the seedlings need to be dived and after a while they should be trans-shipped into permanent pots.
For sowing seeds outdoors, cold stratification must first be done. Sowing is carried out in the fall in boxes. The soil is prepared from leafy soil and sand. It is recommended to grow in a semi-shaded place. Young seedlings will sprout simultaneously from early to mid-summer. At the same time, it is important to regularly clean the area of weeds and fertilize the plants with minerals. It is undesirable to feed manure. During the first year, only 4-5 leaves will form, because at this time the rhizome grows. In the fall, the plant will need to be transferred to the beds, placing them at a distance of 5-10 cm from each other. In this case, you need to update the substrate, add minerals. If the planting is correct, two small shoots will form after two years. After 3-4 years, the seedlings can be transferred to a permanent open area.
Care for dioscorea garden and room
Dioscorea is unpretentious and taking care of her in room conditions is simple. But it should be borne in mind that a plant in a room needs good bright, but diffused lighting. If the direct rays of the sun fall on the flower, the leaves will form sick or the already grown ones will get sick. It should be grown at 20 ° C in summer, and at 11-15 ° C in winter. The air should not be increased, because Dioscorea is drought tolerant. The soil should be light and well drained. For soil, sand, humus, turf and leafy soil are used in a ratio of 1: 1: 1: 1. Indoor dioscorea needs trimming to be shaped in the form of a grid or ladder.
- Watering. In the summer, dioscorea garden needs to be watered often and abundantly. If the weather is not rainy, it is recommended to water it a couple of times every 5-7 days by sprinkling and irrigation. In the fall, watering can be reduced, and when the dormant period comes, and the foliage becomes yellowish, watering should be completely reduced right before the arrival of spring. With the advent of foliage, watering is infrequent. In room conditions, watering should be done as needed. Given that Dioscorea is drought tolerant, the plant is sprayed and watered as the soil dries deeply.
- Top dressing. During the growing season from spring to autumn, fertilize with liquid minerals every 15-20 days. Such dressing is required for room and garden Caucasian vines. When grown outdoors, you can fertilize the plant in a different way. Mulch is used as the soil is assimilated. For mulching, you can take rotted aspen, birch, maple or linden. High-moor peat, compost, and rotting weeds are also good options.
- Transfer. It is necessary to transplant indoor dioscorea every year at the beginning of spring. In this case, it is not necessary to replace the container with another large one, the main thing is to refresh the substrate. In order for the plant to develop better, it is recommended to plant it in a tight container. Old Dioscorea can be transplanted infrequently, but it is important to add fresh soil to the pot every year.
- Diseases and pests. Dioscorea is resistant to diseases and pests, and is least often affected when grown indoors. A spider mite can harm the plant, which sucks out the juice from it, because of which the leaves are deformed and dry out. The symptom of the lesion is a characteristic thin cobweb on the foliage. To kill the pest, it is necessary to treat the leaves of dioscorea with soapy water or sprinkle the leaves with tincture of onion husks. If there are more insects, it is recommended to use Actellik. With a lack of lighting and watering, the leaves turn yellowish and crumble.
Dioscorea Caucasian in landscape design: creating a hedge
Dioscorea Caucasian is a climbing liana, which is always useful to a gardener for landscaping a plot. It is very versatile: if you add a vertical component to the landscape landscape, the dioscorea will hide the wall of a building, a garage, braid an arch, a pillar, a gazebo, etc. Open spaces will become more inviting and densely screened thanks to the plant's rich green textured leaves. Dioscorea also has sufficient resistance to shading that it can decorate a distant corner of the garden. In summer, Dioscorea will attract the eye with its green leaves, and by autumn - with gentle yellow tones. It looks beautiful next to conifers, vineyards, against a purple background. Dahlias, gladioli, etc. can be grown in the neighborhood.
