The study was conducted to assess the effect of sowing dates on the autumn development and overwintering of winter wheat plants in Novosibirsk Oblast. The research was carried out in 2018–2022 on five varieties of winter soft wheat at three sowing dates (the first on August 20, the second on September 1, and the third on September 10). Plant overwintering has been significantly influenced by the following factors: year (18.6%), sowing date (7.7%), variety (19.5%), and interaction between them (24.3%). The sugar content in the tillering node has been significantly influenced by sowing date (22.6%), year (22.8%), and their interaction (17.7%). The highest sugar accumulation in the tillering node has been observed in plants sown at the third sowing date (29.7%). A significant correlation has been found between winter wheat overwintering and sugar content in the tillering node (r = 0.37), hydrothermal coefficient (r = 0.36), and average daily air temperature during the autumn growing season (r = –0.47). Sugar content in the tillering node has also been significantly correlated with plant height (r = –0.60), tillering coefficient (r = –0.58), hydrothermal coefficient (r = 0.34), mean daily air temperature (r = –0.66), and duration of vegetation (r = –0.57). The results of the study indicate the need to optimize the sowing dates of winter wheat to increase its winter hardiness under the conditions of Novosibirsk Oblast. For good overwintering of crop plants under the conditions of Western Siberia, it is advisable to sow them at a later date.
Musinov et al. (Sun,) studied this question.