Agrology (Feb 2023)
Frost resistance and survival of winter wheat after spring rape in the conditions of the Northern Steppe of Ukraine
Abstract
Abstract. The gradual climate warming is leading to emergence of more intensive varieties of winter wheat and therefore urges scientists to improve the technology of its cultivation. Research of the reaction of winter wheat varieties to an atypical predecessor (winter rape), sowing dates and seed sowing rates is gaining relevance. The study was carried out on the research field of the Scientific and Educational Center of Practical Training of the Dnipro State Agrarian and Economic University in 2018–2020 on common low-humus medium-thick silty-medium loam black soil on the loess. Winter wheat plants that had been sown on 25th and 15th of September had the highest values of the frost resistance index. On average, over the years of research, when the plants were frozen at the temperature of –16 ºС for 72 hours, the frost resistance of the Zolotokolosa variety from these sowing dates was 98.1% and 96.7%, respectively. Highest tolerance to low temperatures was exerted by the Selianka variety, equaling 98.4% and 97.1%, and the tolerance of the Podolianka variety was the lowest, 98.1% and 96.3%, respectively. The maximum number of survived winter wheat plants was in the variants of the experiment where sowing was carried out in September 25–26 (97.1%). The survival of winter crops was lower if sown on October 5 (96.0%) and September 15–17 (95.1–96.1%), and the lowest if sown on September 5–7 (94.0–95.0%). The maximum yield (4.90 T/ha) was produced by the Selianka variety sown on 25th–26th of September, at the rate of 5.0 million intact seeds/ha. The Zolotokolosa variety produced the highest yield after being sown on 25th–26th of September at the rate of 5.0 million intact seeds/ha (4.20 t/ha) and sown on 5th–7th of October at the rate of 6.0 million intact seeds/ha (4.21 t/ha). The highest yield from the Podolyanka variety was obtained after sowing in the first decade of October, the sowing rate being 6.0 million seeds/ha (3.76 t/ha).
