Simulation of seed productivity of the rice varieties in the conditions of the South of Ukraine

The processes of simulation yields and water consumption of the rice varieties of domestic selection Ukraine-96, Premium, Viscount with the help of the FAO AquaCrop model are described. As experimental data, we used the results of research on improvement of growing technologies of rice seeds, which were conducted during 2016–2018 years at the Institute of Rice of National Academy of Agrarian Sciences of Ukraine. The research was carried out in accordance with the common requirements of the experiment work and the technique of state strain testing of agricultural crops. The data of the climatic conditions of the South of Ukraine, biometric and structural characteristics of the varieties of culture under investigation, agrotechnics, physical soil and water indicators were introduced into the information system regarding the proposed AquaCrop algorithm and its conceptual provisions. The most optimal for water saving and the amount of biomass received among other simulation scenarios was the option of formation of biologically optimal irrigation schedule with an irrigation interval of allowable depletion 78% of RAW (readily available groundwater in the root zone) and a depth of 20 mm. The summarized results of simulation show that the most effective on the amount of accumulated biomass and yield was the Viscount variety with the values, respectively, 21.11 t/ha, 9.50 t/ha – in 2016 year and 19.20 t/ha, 8.83 t/ha – in 2017 year. Calculated by the program rate of irrigation in 2016 year 860 mm (8,600 m3/ha) was lower than the rate in 2017 year (900 mm) with the same rate of irrigation 200 m3/ha. In 2018, the highest indicators of biomass (21.99 t/ha) and crop yield (10.12 t/ha) were obtained in the variety Ukraine-96 with the irrigation rate of 880 mm. The results of our research with using FAO AquaCrop agrotechnology demonstrate this system as a progressive tool with a future perspective for planning the rice production process in crop yield simulation with the aim of comparison of existing and future perspective varieties according to their properties, creating the most optimal irrigation strategies for water saving and less pressure on environment.