Abstract
The article presents the results of a study on the duration of the vegetation period of rapeseed, one of the valuable and promising oilseed crops, in the conditions of Abay region. The aim of the study is to assess the ripening potential of rapeseed varieties of foreign selection in the soil and climatic conditions of the region. Rapeseed is a crop that can grow in a wide range of soil conditions, except for marshy, very light and sandy soils. Currently, research on rapeseed cultivation is actively underway. The soils of the area where the study was conducted belong to the light chestnut type. The climate is sharply continental, with a large daily and annual temperature range. Winters are harsh, summers are hot. The study used the ХNА, ХNB, and ХNC varieties of foreign (PRC) selection. In recent years, a large number of rapeseed varieties of domestic and foreign selection have been recommended for production. Determining the duration of the rapeseed vegetation period is important for determining the optimal sowing and harvesting times. Phenological observations were conducted in the first half of the day. The duration of the vegetation period for the ХNB and ХNC varieties was 89-92 days. The ХNA variety did not mature in the conditions of the region. The timing of the onset of rapeseed variety development phases was determined. It was found that the timing of development phases depends on weather conditions and the genetic characteristics of the varieties.