Authors: E. O. SHESTAKOVA, postgraduate student of the plant physiology department, F. V. EROSHENKO, doctor of biological sciences, head of the plant physiology department, I. G. STORCHAK, candidate of agricultural sciences, senior researcher of department of plant physiology, North-Caucasian Federal Scientific Agrarian Center (49 Nikonova Str., 356241, Mikhailovsk, Stavropol Krai; phone: 8 988 858-18-85, 8 962 454-14-96, 8 918 747-02-56; e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it., This email address is being protected from spambots. You need JavaScript enabled to view it., This email address is being protected from spambots. You need JavaScript enabled to view it.)
Keywords: radiation sowing mode, photosynthetically active radiation (PAR), winter wheat, elements of cultivation technol- ogy, variety, predecessor, level of mineral nutrition, sowing terms, seeding rates.
Abstract: The study of the influence of various elements of the cultivation of wheat wheat on the radiation regime of crops is an urgent task, the solution of which will provide a scientific justification for the development of technological methods of cultivation that affect the efficiency of use of photosynthetically active radiation by crops. The aim of the research was: to study the effect of predecessors, the level of mineral nutrition, the timing and seeding rates on the radiation regime of winter wheat sowing of various varieties. On average, for the studied variants during the period of grain loading, the upper half of winter wheat sowing absorbs only 33.9 % of the incoming photosynthetically active radiation, and the lower half – 66.1 %. Varietal features have a great influence on the radiation regime of crops. Thus, the smallest difference in the absorption of incoming PAR by the up- per and lower parts of sowing is observed in the “Zustrich” variety – о40.2 and 59.8 %, and in the “Anisimovka” variety, these figures are 29.2 % and 70.8 %, respectively. The seeding rates have a significant effect on the absorption coefficient of photo- synthetically active radiation. Thus, on average, over the years of research, the minimum value was observed at 4 million viable seeds per hectare and was less than at 5 and 6 million by 6.8 and 7.5 %, respectively. In the arid 2018, the ear predecessor on the version without fertilizers noted the maximum value of the absorption coefficient – 80 %, which is 11.1 % and 4.5 % more than in 2016 and 2017, respectively. In 2018, at the early time of sowing, the minimum values of the PAR absorption coefficient were obtained - 69.44 %, which is less than in 2016 and 2017 by 9.3 and 11.3 %, respectively. Thus, various technological methods of growing winter wheat, such as variety, precursor, mineral fertilizers, sowing dates and seeding rates, have a significant impact on the radiation regime of sowing.
