Variability of the growing season period in F₂-F₄ hybrids of cotton in different soil-climate zones of Uzbekistan

Tashkent State Agrarian University, 2, University street, Tashkent, 100140, Uzbekistan

^* Corresponding author: saida-68@mail.ru

Abstract

One of the most crucial topics in cotton breeding is the identification of plant reactions to the environment, including its stressful circumstances and the amount of plant responsiveness to biotic and abiotic stimuli. Plants continuously interact with their environment as they grow and develop; this interaction results in the organism's ability to adapt, or adaptation. For the duration of the plant's existence, the process of adaptation never comes to a stop. The most crucial evolutionary component that enables the adaptability of species and populations to changing environmental conditions is variability, a feature of an organism that represents the processes of its interaction with the environment. Variability is the foundation of adaptation. An assessment was made of the variability of the length of the growing season in four hybrid combinations of medium staple cotton in 2018-2020 in the Tashkent, Fergana and Kashkadarya regions of the Republic of Uzbekistan. It has been established that the duration of the growing season depends mainly on the geographical latitude and genotype of the plant: in the more northern growing zone (Tashkent region), both the average length of the growing season and the amplitude of the trait variability increase compared to the indicators in the Fergana and Kashkadarya regions.