Frost resistance of generative and vegetative buds in sour cherry varieties in Tatarstan

Sour cherry ( Prunus cerasus L.) is a valuable stone fruit crop in the Central Belt of Russia, the Volga Region, and the Republic of Tatarstan. It is very popular among the population due to its good-tasting fruits containing nutritious and biologically active substances. In terms of winter hardiness, it surpasses other types of stone fruit crops: plum, cherry plum, apricots. Not all varieties of sour cherry bred in Russia are adapted to the harsh winter conditions of Tatarstan. Unfavorable winter conditions often damage the generative buds of sour cherry plants. The purpose of the research is to determine the frost resistance of generative and vegetative buds in sour cherry varieties in Tatarstan. Freezing of generative and vegetative buds, productivity in sour cherry varieties were determined according to the methodology of the All-Russian Research Institute of Fruit Crop Breeding. As a result of the research, it was established that in 2023–2024, in the laboratory of fruit crop breeding of the Tatar Research Institute of Agriculture, there were no sour cherry varieties with highly frost-resistant, frost-resistant and moderately frost-resistant generative buds. According to the resistance of generative buds to frost of -38 °C, sour cherry varieties were divided into the following groups: IV — slightly frost-resistant Obilnaya (k.), Shakirovskaya (k.), Livenskaya, Shelangovskaya, Truzhenitsa Tatarii, Pamyat Sakharova, Volzhskaya, Zarya Tatarii, Novella; V — not frost-resistant Sevastyanovskaya, Tveritinovskaya, Rovesnitsa, Krasa Tatarii, Dessertnaya Morozova. Vegetative buds of sour cherry varieties showed higher resistance to frost of -38 °C than generative buds. In 2024, there were no sour cherry varieties with highly frost-resistant vegetative buds. The following sour cherry varieties were included in the II group of vegetative bud resistance (frost-resistant): Obilnaya (k.), Shelangovskaya, Truzhenitsa Tatarii, Livenskaya, Volzhskaya, Shakirovskaya (k.), Pamyat Sakharov, Zarya Tatarii.