Effect of some meteorological parameters on yields and the content of macroelements in winter wheat grain.

The volume and quality of cereal yields are largely determined by the course of climatic conditions, mainly air temperature and precipitation. The objective of this paper was to determine the impact of meteorological conditions during the spring and summer growing season of winter wheat on grain yields (in 1993-2012) and on the content of nutrients in grain (in 19942009). The study was based on a field experiment conducted at the Research Station located in Tomaszkowo near Olsztyn, which belongs to the University of Warmia and Mazury in Olsztyn. The impact of meteorological parameters during the spring and summer season on winter wheat yields and the content of elements was investigated by correlation analysis and multiple regression analysis. The examined weather conditions in the spring and summer did not produce any significant impact on the yields. However, some tendencies were noted, indicating that the average minimum temperature had the highest negative impact and the number of days with precipitation produced the highest positive impact on winter wheat yielding. Among the tested macroelements (N, P, K, Mg, Ca), the analyzed meteorological parameters significantly affected the content of nitrogen and phosphorus in winter wheat grain. The accumulation of nitrogen was positively influenced by precipitation, yet significantly negatively affected by the minimum temperature during the spring and summer growing season. The mean daily air temperature during that time had a significant negative impact on the concentration of phosphorus in wheat grain, which was significantly positively raised by the average minimum daily air temperature during the growing season.