Patterns for changes in climatic factors in the hop growing zone of Ukraine and their impact on hop genotypes

Abstract

Purpose. Analysis of the directions and trends of changes in climatic factors in the hop growing zone in Ukraine and the determination of the features and level of their impact on plants. Methods: field, laboratory, statistical, analytical, computational and comparative. Results. It was determined that the increase in the average temperatures in the Polissia zone in the last decade has already been more than 1.5 °С, and by 2050 the increase will be about 3.2 °С. In the course of conducting research, the analysis of the temperature regime of the climate showed that since 2004 there has been a clear trend towards an increase in average monthly temperatures with an increase in the frequency and dynamics of air temperatures, especially in a cold season. The dynamics of precipitation stage during the vegetation period 2004-2024 shows some trends towards its gradual decrease. Under the average long-term indicator (climatic norm) of 351 mm per 6 months of vegetation, over the last 20 years of observation, the average precipitation was 329 mm. Analysis of the results (Global ETО_v3) showed that currently the calculated global GED for the area of out research is 0,6–0,8 as the amount of annual precipitation decreased to 450–550 mm. The results of the research show that with a summer rainfall close to the multi-year norm (150–210 mm) the average yield of genotype sample fluctuated within 1,6–1,8 t/ha. With a rainfall of more than 220 mm, the indicators were close to 2,0 t/ha. The determining factor is not so much the amount of precipitation as its distribution during the summer months. It was established that the ambient temperature within the current limits does not have a decisive influence on the accumulation of alfa-acids in the cones of hop plants. Conclusions. According to the results of the analysis based on on publicly available global climate change models (GCM), it was determined that the increase in the average temperatures in the research area in the last decade was more than 1,5 °С, and is projected to increase further. The frequency of duration of the positive critical temperatures, which significantly exceed climatic norms, are also increasing. It was established that the total level of precipitation in the area is decreasing, especially in the second part of the growing season. The obtained experimantal data also made it possible to characterize the main patterns of the influence of changes in air moisture availability and temperature on the productivity and quality indicators of the hop genotype of the working selection collection.