Adaptation

Adaptation of an organism determines the possibility to exist in this environment. Any adaptation of a specific historical stage will accommodate, the process – adaptatsiogeneza flowing in certain geographical areas (Habitats) with their usual set of external environmental conditions (adaptive zones) and meet certain communities of living organisms inhabiting them (biocenoses). Adaptation is always emerges and develops a influence of three main factors is organic. evolution – variation, heredity and selection (natural and artificial). Adaptation may be ontogenetic – the body's ability to adapt to its individual development to changing external conditions. The plant can adapt to both constantly and systematically acting within the individual life environmental factors, and to the fluctuating.

Ontogenetic adaptation can be genotypic, if there is a selection of hereditarily determined (the change of the genotype) higher adaptability to changed conditions, or phenotypic, when volatility limited response rate, defined a stable genotype. In plants, the source of adaptation may be non-hereditary and adaptive responses – the modifications. If there are signs of plants that have no value to them life in this environment, but are adaptive B changed with time conditions, adaptation is a prospective, or preadaptation. Adaptation can be behavioral or physiological (the set physiological. reactions that underlie the organism's adaptation to changing environmental conditions and to preserve the relative constancy of its internal environment – homeostasis). These forms of adaptation are not mutually exclusive other. The fitness of the organism as a whole is determined by the weakest link in the chain of environmental his needs.

The limits of a species are determined by the developmental stage of individuals for which they tolerance (endurance) is minimal. Each of the environmental factors that act which undergoes this kind has the limiting values (maximum and minimum), corresponding to the boundaries of tolerance of organisms form (law Shelford tolerance). Type of grape variety, or even may have a high tolerance towards one factor, such as temperature, but low for another, such as salinity or pH of the soil. Miscellaneous tolerance in the species of grapes in relation to k.-l. factor explains their evolution. Thus, the species Vitis vinifera varieties resistant to mildew weakly, oidium and phylloxera, and wild American species – are resistant. Homeland phylloxera, downy mildew and oidium The south-east. part of the North. America, where they adapted to feeding on grapes. As a result of a long evolution in constant contact parasites and grape plants are mutually adapted and changed. At natural selection survival of the adapted plants, and thus created resistant strains of grapes. European varieties, which existed outside the area of origin of these parasites could not adapt to them and proved to be unstable. This phenomenon, when one of the ancestral form is a wide variety of forms or species occupying different habitats and the evolution of acquiring different adaptive features, is called adaptive radiation. Tolerance of different types of grapes with respect to temperature is also different. Some species, such as the Amur grape, and wild American species, stand temperatures down to -40 C, and many European species are damaged even at -15 C. In the selection of grapes to create a stable heterogeneous population, in which adaptive morpho-physiological. organization is not based on mutation and in combination. That is, mutations, and their combination under the control of the selection of a source of adaptation, while selection becomes important leading factor of the adaptive organization of plants.