Having learned to cultivate plants, man began to make attempts to improve them, preserve and reproduce the best quality forms. Even in ancient times, many varieties of wheat, grapes, and various fruit plants were created. This is how the science of breeding new varieties of plants arose - selection.
Separation of varieties by origin
Variety - what is it? A variety is a stable group of plants created by breeding methods and possessing hereditary characteristics within this group. Each plant variety is distinguished by a set of morphological, biological, economic features that determine its characteristics. The description of the variety includes several features. The origin testifies to the source material used to create it. There is a huge variety of cultivated and wild plants, from which the right specimens are selected for selection. According to this principle, such a capacious concept as a variety is divided into two types. What are its varieties - below.
1. Local - obtained through a multi-year selection conducted by the population in a particular area. They are well adapted 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:
- varieties-lines are obtained by individual selection of offspring from one self-pollinating crop, due to which they are characterized by similarity in characteristics and properties, but over time, due to mutations, they lose this uniformity;
- Population cultivars are usually local cultivars formed by mass cross-pollination crop breeding, which simultaneously occurs natural hybridization with other related plants;
- clone varieties are the offspring of a single vegetatively propagated culture and are highly uniform and stable;
- hybrid varieties are formed by crossing crops with a set of traits of several generations, selecting plants with the desired properties.
Biological signs
Breeding variety. What does it represent according to the following economic and biological characteristics?
1. Resistance to adverse natural factors:
- winter-hardy - crops resistant to low temperatures, suitable for growing in areas of the middle zone and more northern, depending on the variety;
- drought-tolerant – capable of withstanding significant lack of moisture with minimal yield loss.
2. The duration of the growing season is the period of time during which the plant must go through the entire cycle of its development. It depends on the type of crop, variety, thermophilicity or cold resistance, and many others.factors. This is an important biological indicator necessary for the correct zoning 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 per tree.
4. Self-fertility characterizes the ability of plants to produce ovaries during self-pollination. If this indicator is low or equal to zero, then there should be a plant nearby that will become a pollinator for him.
5. Taste qualities differ 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 the 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 features:
- flower color;
- shape and jagged edge of the leaves;
- plant height;
- for potatoes - the color of the skin and the shape of the tubers.
Over time, the new variety losesvaluable properties, and scientific and technological progress in agriculture places ever higher demands on the crops produced, so the process of creating and improving varieties should 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 Plant Breeds? It is provided to protect the interests of breeders and the possibility of reimbursement of the funds spent by them. To obtain legal protection, this variety must pass a technical examination, which includes three characteristics.
1. The criterion for the distinctness of a variety is a photo, its description must be clearly different from any other known at the moment.
2. Variety uniformity criterion – plants belonging to the proposed variety must be uniform under a given propagation method.
3. Stability criterion - all signs and properties must remain the same after repeated reproduction.
After a new plant variety passes all the tests in a special area, it is assigned a variety name and entered into the state register of breeding achievements.
The creation of new varieties provides humanity with more productive crops that are more resistant to many adverse environmental factors. Life puts forward a variety of new requirements for crops, so methods are now being developed to accelerate selection, which in the future will reduce the time for breeding new high-quality plant varieties.
