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Methods of preliminary cultivar research and testing of grape cultivars

For agronomists

5 min read

VITICULTURE V

Preliminary study: how to identify a promising grapevine on-site

Selecting grapevines using the climatic analogue method is only the first theoretical step. For a cultivar to produce a stable harvest in a specific micro-district, it must be tested under local conditions. To this end, preliminary cultivar study and cultivar testing are conducted, which help determine the real quality of the berry and the intended use of the harvest.

The preliminary study begins with an expeditionary survey of existing plantings directly on farms. This method allows for the identification of valuable indigenous cultivars that may be growing in plots as admixtures to the main cultivar mix. Fieldwork is based on a clear algorithm.

  1. Examine vineyards during the harvest ripening period.
  2. Determine the morphological and economic-technological traits of the bushes.
  3. Verify the identified admixtures for identity with known cultivars.
  4. Prepare cuttings for propagation and stationary study.

Before propagating the found bush, be sure to check it against ampelographic reference books. It may turn out to be a previously studied cultivar that was introduced earlier under a different local name.

Identified promising forms are sent to stationary plots for detailed study. Here, the bushes are planted in collections, and a complete ampelographic description is compiled. Specialists pay particular attention to the behavior of the plants in specific soil and climatic conditions.

When assessing the agrobiological traits of grapevines in the field, key parameters of survival and productivity are monitored. It is important for the agronomist to evaluate the vine's response to limiting environmental factors and the cultivar-specific cultivation technology. Observations are conducted systematically throughout the entire growing season.

  • Resistance to drought, frost, and other adverse environmental factors;
  • Plant resistance to local diseases and pests;
  • The nature of the progression of development phases in the small annual cycle;
  • Indicators of fruitfulness and total productivity of the bushes;
  • Response of the grapevine to elements of cultivar-specific agrotechnics.

Cultivar testing: from small plots to industrial scales

Cultivar testing is divided into three sequential stages: small-scale, competitive, and production. They allow for a comprehensive assessment of the crop before mass introduction into production. Each stage solves its own tasks — from point-based assessment of clones to bringing the cultivar to large areas.

Test type When applied Which cultivars are included
Small-scale In areas with an existing cultivar mix to improve it or refine its specialization New breeding cultivars, improved clones, valuable introduced cultivars. Comparison is made against a standard.
Competitive In new viticulture areas or for new directions of use in the absence of standards Cultivars based on climatic analogues, new and well-proven forms.
Production For evaluating cultivars on large areas on farms and experimental bases Cultivars after small-scale or competitive testing, from collections and breeding plots.

After the preliminary stages, the best cultivars are sent for state cultivar testing. It is conducted according to a unified methodology at special state cultivar testing sites and collection bases of research institutions. This allows for obtaining objective data for including cultivars in the registry and replacing low-value plantings.

All state cultivar testing sites operate according to a unified methodology and reporting forms, which ensures the comparability of results in different climatic zones.

  • Number of testing regions — 11
  • Number of state cultivar testing sites — about 100
  • Cultivars at one site — from 10 to 50 or more
Indicator Value
Number of tested cultivars 10–50 and more

To objectively evaluate a new grapevine cultivar, it is compared with a reference standard. Only those cultivars that are already regionalized in your area, match the new one in terms of the intended use and ripening dates, are chosen as the control. All observations and records are kept strictly according to the methodology of the State Commission for Cultivar Testing of Agricultural Crops.

The cultivars being compared must be in absolutely identical conditions. Cultivation technology is maintained at the level of the region's leading farms, while the care must be identical for each group of cultivars and fully comply with their biological characteristics.

Observation data is collected and summarized over several years. Based on these materials, a conclusion is drawn about the economic value of the studied grapevine. If a new cultivar surpasses the standards in key indicators or provides unique product quality, documents are sent to the inspectorate of the State Commission for its inclusion among the regionalized ones.

How the state cultivar selection system works

Every year, the State Commission for Cultivar Testing of Agricultural Crops convenes a plenum. At these meetings, experts analyze the results of the work of state cultivar testing sites and form cultivar policy. Plenum participants perform the following functions:

  • review testing results, proposals from state cultivar testing sites and inspectorates on the regionalization of new cultivars, as well as on the exclusion of obsolete and low-value ones;
  • make decisions on including new, promising cultivars in state cultivar testing;
  • approve changes and additions to the methodology of state cultivar testing;
  • review proposals regarding authorship for new cultivars.

The decisions of the State Commission plenum on cultivar zoning do not come into force automatically. This is a regulated procedure for executive authorities. These decisions are finally approved by the Councils of Ministers of the Union Republics.

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