Having learned to cultivate plants, a man began to make attempts to improve them, preserve and reproduce the highest quality forms. Even in ancient times, many varieties of wheat, grapes, and various fruit plants were created . So the science of breeding new varieties of plants - selection.
Separation of varieties by origin
Variety - what is it? A variety is a stable group of plants created by selection methods and having hereditary traits within this group. Each plant variety is distinguished by a combination of morphological, biological, economic characteristics that determine its characteristics. The variety description includes several characteristics. The origin indicates the source material used to create it. There is a huge variety of cultivated and wild plants, from which the necessary specimens are selected for selection. According to this principle, such a broad concept as a variety is divided into two types. What are its varieties - below.
1. Local - obtained through years of selection conducted by the population in a specific area. They are distinguished by good adaptability to the natural conditions of the region.
2. Breeding - created on the basis of scientific methods and, depending on the method of breeding, in turn, are divided into several groups:
- line varieties are obtained by individual selection of offspring from one self-pollinating crop, due to which they are characterized by the similarity of characters and properties, however, over time, due to mutations, they lose this uniformity;
- population varieties are usually local varieties formed by the method of mass selection of cross-pollinating crops, in which natural hybridization with other related plants occurs simultaneously;
- clone varieties are the offspring of one vegetatively propagated crop and are highly uniform and stable;
- hybrid varieties are formed by crossing cultures with a set of traits of several generations, selecting plants with the desired properties.
Biological signs
Breeding grade. What does he represent by the following economic and biological features?
1. Resistance to adverse environmental factors:
- winter-hardy - crops resistant to low temperatures, suitable for cultivation in areas of the middle band and more northern, depending on the variety;
- drought tolerant - able to tolerate a significant lack of moisture with minimal yield loss.
2. The duration of the growing season - the period of time for which the plant must go through the entire cycle of its development. It depends on the type of culture, variety, thermophilic or cold hardiness and many other factors. This is an important biological indicator necessary for the correct regionalization of crops.
3. Productivity is determined by the product of productivity, that is, the average yield of one plant and the average number of plants located per unit area. For perennial woody plants, it is estimated already in adulthood, usually in kilograms from one tree.
4. Self-fertility characterizes the ability of plants to make ovaries during self-pollination. If this indicator is low or equal to zero, then there must be a plant nearby, which will become a pollinator for it.
5. Taste qualities vary depending on the content of acids and sugars in fruits and berries.
6. Resistance to pests and diseases is a very important quality for obtaining environmentally friendly products, since treatment with pesticides leads to their accumulation in plants and in the environment. This direction in breeding is not only one of the main, but also the most difficult, since the potential for variability and the ability to reproduce in pests and pathogenic microorganisms is very high.
7. The ability of shoots to root is important mainly for berry bushes.
External characteristics
Varieties differ in morphological characters:
- coloring flowers;
- the shape and rugged edge of the leaves;
- plant height;
- for potatoes - skin color and shape of tubers.
Over time, the new variety loses its valuable properties, and scientific and technological progress in agriculture places higher demands on produced crops, so the process of creating and improving varieties must be permanent.
Examination of a new variety
So, a new variety has been bred. What is the legal protection of the International Union for the Protection of Breeding Achievements? It is provided to protect the interests of breeders and the possibility of reimbursing the funds spent by them. To obtain legal protection, this variety must undergo a technical examination, which includes three characteristics.
1. The criterion for the distinguishability of the variety is a photo, its description should clearly differ from any other known at this time.
2. The criterion for the uniformity of the variety - plants belonging to the proposed variety must be the same with this method of propagation.
3. Stability criterion - all signs and properties should remain the same after repeated reproduction.
After a new plant variety passes all the tests in a special area, it is assigned a varietal name and entered into the state registry of selection achievements.
The creation of new varieties provides mankind with more productive crops that are more resistant to many adverse environmental factors. Life puts forward new diverse requirements for crops, therefore, methods are currently being developed to accelerate selection, which in the future will shorten the time for breeding new high-quality plant varieties.