STUDYING THE HEAT RESISTANCE OF GOLDEN PINE VARIETIES

Abstract

The article presents the results of a scientific study conducted in 2022-2024 to assess the tolerance of golden currant (Ribes aureum) varieties (Siyuma, Elixir, Yadgor, Rukhshona, Lyovushka, Podarok Ariadne and Valentin) to high temperature factors in the sharply continental and dry-hot climate of Uzbekistan. During the study, the degree of tissue damage to leaves under the influence of various critical temperatures (+40°C to +60°C) using a water bath in laboratory conditions and the difference in leaf temperature from the ambient temperature due to the transpiration process in natural field conditions (thermoregulation properties) were comparatively studied. The analyzes showed that at temperatures of +40...+45°C, leaf damage was minimal (4.5- 18.5%), while damage increased sharply when the temperature reached +55...+60°C. Among the varieties studied, the variety "Elixir" was the most resistant to high temperatures, and the level of damage was significantly lower. It was also found that in field conditions, the leaf temperature of the variety “Elixir” was up to 7.9°C cooler than the outside air temperature, demonstrating strong thermoregulation capabilities. This variety “Elixir” is recommended as a valuable primary source for the establishment of plantations with consistently high yields in arid and hot regions and for breeding. The analyzes showed that at temperatures of +40...+45°C, leaf damage was minimal (4.5-18.5%), while when the temperature reached +55...+60°C, damage increased sharply. Among the varieties studied, the varieties “Elixir” and “Podarok Ariadne” were the most resistant to high temperatures, and the level of damage was significantly lower. Also, in field conditions, the leaf temperature of the “Elixir” variety was cooler than the outdoor air temperature by 7.9°С, and it showed a strong ability of thermoregulation. These cultivars are recommended as valuable primary sources for establishment and breeding of regular high yielding plantations in arid and hot regions.