Breeding is the science and process of developing or selecting new varieties and cultivars of cultivated plants in relation to specific environmental conditions and in accordance with production requirements. The goal of breeding is to create varieties that surpass the best local standards in yield and quality or meet new economic demands, including the expansion of crops into new regions.

The term originates from the Latin selectio (selection). In this context, breeding is understood as artificial selection carried out by humans, as opposed to natural selection. Natural selection occurs in nature without active human intervention as an interaction between the variability of living matter and the environment, directing evolution. Breeding is a form of active intervention in nature that directs its processes. According to N. I. Vavilov's definition (1915), breeding is "evolution directed by the will of man."

The development of breeding is linked to the history of humanity, science, and technology. At early stages, the process was limited to selecting the best wild forms. Later, new forms were obtained by sowing seeds from natural pollination, hybridization, and selecting mutations.

The modern breeding process includes the following stages:

  • Studying the breeding task in accordance with economic orders and the conditions of a specific region.
  • Selecting parent material based on the study of local varieties and the global diversity of forms.
  • Biological study of the plant.
  • Applying methods for the artificial modification of heredity (obtaining polyploids and mutations).
  • Creating specific environmental conditions at various stages of plant development.
  • Culling and selecting new created forms based on various characteristics for further work or comparative trials against local standards.

The timeframe for developing a variety ranges from 2 to 15 years, depending on the biology of the plant, the complexity of the task, and the organization of work. Grape breeding relies on the methods of I. V. Michurin, which include harsh environmental conditions for growing hybrid seedlings that correspond to the goals of breeding, as well as specific culling techniques.

Origin of the Cultivated Grape

Grapes entered cultivation more than 6,000 years ago, as evidenced by monuments confirming their use for food and processing into wine. The centers of diversity for the wild grape Vitis vinifera coincide with the ancient hearths of human culture in Asia Minor and Northern Iran.

There are three main theories regarding the origin of the European cultivated grape:

  1. Theory of Alphonse de Candolle and N. I. Vavilov: grapes entered cultivation in Transcaucasia, Northern Iran, and Asia Minor, from where they spread throughout Europe.
  2. Theory of S. I. Korzhinsky and Chetolini: grapes were introduced into cultivation independently in many places along the Mediterranean coast, in Transcaucasia, and Asia Minor from local wild forms of Vitis silvestris Gmel.
  3. Theory of M. G. Popov: table grape varieties were introduced into cultivation from local wild forms (Vitis vinifera spontanea Pop.) in Central Asia. They subsequently penetrated into the Caucasus and Europe, where crossbreeding with local Vitis silvestris gave rise to wine varieties.

The centuries-long process of transitioning from artificial selection to introduction, natural hybridization of cultivated and wild forms, and repeated artificial selection accounts for the high polymorphism of the grape.

Historical Types of Grape Breeding

The development of grape breeding is divided into four main types:

The first type (selection from the wild). Consists of searching wild thickets for plants with the best fruit and moving them closer to human habitations. This method is still applied today in areas where wild grapes grow. In this manner, the varieties Dag-memidon, Dag-kara-uzyum, and Ali-shaytan were introduced into cultivation in the Western Kopet Dag (Turkmenistan); in Transcaucasia (Kakheti, Imereti, Abkhazia, Azerbaijan, Armenia), most local varieties originated from the forest. In the USA, old varieties of the southern Atlantic states (Carolina, Florida) were introduced into cultivation from wild forms of Vitis rotundifolia, while other North American varieties derived from Vitis riparia, Vitis labrusca, and Vitis aestivalis.

The second type (sowing seeds from natural pollination). Appeared later and is based on obtaining new varieties by sowing seeds from open cross-pollination, followed by vegetative propagation of the selected best forms. Grapes cross-pollinate easily, causing seeds from a single plant to yield a wide segregation of traits in the seedlings. The method is mentioned by Theophrastus in the 3rd century BC. The bulk of currently cultivated varieties was obtained by this method. In the 18th and 19th centuries, originators such as Jacques Vibert, Malingre, Courtiller, Bouchet, Salomon, Foster, Pirovano, and Van Mons obtained hundreds of varieties this way.

The third type (clonal selection). Consists of improving varieties by selecting the most productive and high-quality vines (bushes) and shoots on them for vegetative propagation. The necessity of such selection was described by Columella and Palladius. This method is widely distributed in modern viticulture systems.

The fourth type (hybridization). Began to be applied later than the others and went through two stages of development:

  1. Intraspecific hybridization: crossbreeding European varieties to improve their quality (varieties by originators Müller-Thurgau, Pirovano, Bouchet, Rasche, etc.).
  2. Interspecific hybridization: crossbreeding Vitis vinifera with American grape species to obtain varieties (direct producers) resistant to phylloxera, fungal diseases, and cold, or to develop phylloxera- and lime-resistant rootstocks (the work of originators Couderc, Seibel, de Grasset, Foëx, Hansen, Baco, Munson, Michurin, etc.).