Contents of the article:
In its wild form, potatoes are a perennial plant of the family Solanaceae, originating from South America. For tubers, potatoes have been cultivated for more than two and a half thousand years. And modern breeders and biologists are tirelessly working on new varieties.
Wild predecessors of all cultivated potato varieties
As a crop, potatoes are grown as an annual plant, and two closely related potato species are spread throughout the world:
- Komb or Chilean potatoes, originally from Peru and Bolivia, are widely distributed in 130 regions of the world with moderateclimate. The spread of this type of potato began in the XVI century, and by the 19th century, the culture became widespread, becoming the fifth in the ranking of agricultural plants.
- Andean potato, natively grown on the South American continent, has been decisive for creating many modern varieties and hybrids due to polymorphism.
Tubers, for which potatoes are cultivated, begin to form with the appearance of the first buds on the bushes. From a biological point of view, a tuber is a hypertrophied rhizome that becomes a kind of storage for nutrients.
Classification of potatoes by purpose
Today, depending on the content in potato tubers, sugars, vitamins, proteins and starch are divided into four groups.
- Table potatoes is a vegetable that occupies one of the first places in the diet of many nations. Tubers of these varieties differ in large or medium size. They are round, with thin skinned and not too deep eyes. When creating table varieties, particular attention is paid to the content in tubers of vitamin C and starch, which should not be more than 12-18%.
- Technical potatoes are the raw material for the production of alcohol and starch, therefore an increased, more than 16%, content of this component in such varieties is welcome. But protein technical potato is poor.
- Feed potatoes produce large starchy, protein-rich tubers. Since the importance of potatoes as a fodder crop has been growing recently, the high yield of varieties is extremely important.
- Universal varieties can combine the properties of all listed groups.
For many years, the presence on the summer cottages and farm plantations of potatoes, everyone is used to the fact that the external color of tubers can be almost white, and brown-yellow, pink or almost violet. But on the cut, until recently, the potatoes remained white or slightly yellow.
Where does the purple and red potato have an unusual color?
But today breeders offer to plant quite unusual types of potatoes with multi-colored flesh. An amazing color gamut of potatoes is obliged to the biochemical composition, and more specifically, to anthocyanins and carotenoids. If tubers with traditional white pulp of provitamin A contain no more than 100 mg per 100 grams of potatoes, in varieties with a yellow core of this substance is already twice as much. And the brighter the color of the tuber, the greater the concentration of provitamin A. In orange and red potatoes its content reaches 500-2000 mg.
The concentration of anthocyanins, which provide purple, purple or purple color of the flesh and peel, in brightly colored tubers is two dozen times higher than in light-colored table varieties. Per 100 grams of purple or blue potatoes can be from 9 to 40 mg of anthocyanins. Moreover, the concentration of this natural dye and carotene is always higher at the peel. But inside the pulp, these substances can be distributed unevenly, which allowed breeders to obtain plants with variegated both outside and inside tubers.
In addition, there are more bioflavonoids in red, blue or purple potatoes than in traditional varieties with a light colored flesh. But the starch in colored tubers is much smaller, so they can be used for dietary and medical nutrition, and sometimes even raw. The active selection of all new colored varieties and their growing popularity among gardeners suggests that not all the useful aspects of potatoes have been studied and used. Conducted by biologists and physicians of Korea and the United States, studies have shown that the introduction of violet and red coloration into tubers helps the body resist atherosclerosis and oncological diseases.
Substances in the composition of red and purple potatoes have a beneficial effect on the state of the organs of vision and vessels, prevent premature aging and help fight heart diseases.
Red and Blue Potatoes from CIS Breeders
Not only Western breeders, but also scientists from Belarus and Russia are engaged in breeding varieties that give tubers with colored pulp. Employees of the Research Institute of Plant Industry of the Russian Federation obtained high-yielding hybrids of purple and red potatoes, which were successfully zoned in the middle zone of the country.
But the first colored potatoes in Russia were obtained in the Tomsk region. Since 2007, the cultivation of orange, pink purple and blue potatoes has been underway. Siberian scientists have zoned and several interesting types of potatoes with a high content of carotene and anthocyanins are already massively grown.
Thanks to the seed material obtained from the Peruvian Potato Center, the Research Institute of Crop. Vavilov, as well as from research centers in the USA and Germany, Belarusian researchers engaged in promising developments managed to create more than seventy hybrids, which are as bright as world analogues.
Conventionally useful types of potatoes
The demand for brightly colored types of potatoes, most often obtained from interspecific crossing and careful selection, is steadily growing in the world, which is facilitated by the curiosity of gardeners and the pronounced beneficial properties of such tubers. Biological research is not limited to such a selection.
Genetically modified cultivar Russet Burbank New Leaf was created on the basis of potato with red-brown skin distributed in the USA, one of the largest companies engaged in plant genetics.
- Externally, such potatoes are little different from the usual yellow or white.
- It has yellowish friable pulp and leathery dense skin.
- When grown, the variety shows high yield and resistance to diseases and damage to the Colorado potato beetle.
- It uses a number of the largest fast food chains in the world.
- This variety, which dominates plantings in the USA and Australia, is used as food and feed potatoes.
But as a result of studies conducted in 2009 by Russian physicians, agricultural plants with altered genetics, including similar types of potatoes, were not recognized as beneficial to humans. In experimental animals that ate such tubers, pathological changes in the internal organs were detected, therefore, genetically modified potatoes are not allowed for distribution and cultivation in Russia.
No matter how popular the colored tubers are, there is one type of potato of unusual color that only harms a person. It is well known to gardeners green potatoes, which became such after a long stay in the light.
Under the influence of illumination in the tubers, the natural alkaloid, solanine, begins to accumulate. So the plant protects the tubers from the effects of the environment and diseases, but solanine is not at all beneficial for humans.
Edible Sweet Potato, Sweet Potato
If a real potato is a vegetable related to nightshade, peppers and tomatoes, then for a sweet potato, which gives large starchy tubers, the closest relatives will be wild-growing bindweeds and garden hypoma.
Sweet potato yam is cultivated today in many Asian countries, in Africa and the United States, because of its nutritional and beneficial qualities. This is a worldwide popular food culture, whose birthplace is in the mountainous regions of Colombia and Peru. Like ordinary potatoes, sweet potatoes, depending on the variety, can produce tubers of not very different colors.
Long-known varieties, so rich in carotene, that their orange tubers outperformed carrots. Yams containing a large number of anthocyanins, showing similar properties to traditional violet potatoes, are successfully grown. But in terms of calcium, carbohydrates and iron content, potatoes are inferior to sweet potatoes, which, moreover, are one and a half times more nutritious.
- In the tropics and subtropics zone, sweet potato sweet potatoes are grown as a perennial crop, and in this case the tubers even reach 10 kg weight.
- In temperate climate conditions in the annual crop, it is possible to grow the earliest ripening varieties, whose tubers weigh about 3 kg. Russia has a successful experience in cultivating sweet potatoes with a growing season of up to 110 days.
In the world, however, many varieties of high-yielding sweet potatoes, differing not only in terms of ripening, coloring of the flesh and rind of tubers, but also in their taste, are bred. If some sweet potatoes really have a sweet taste, others cannot be distinguished from traditional potatoes. There are varieties with a creamy and nutty flavor on the palate.
