INFLUENCE OF WEATHER CONDITIONS ON GRAIN YIELD, OIL CONTENT AND OIL YIELD OF NEW OS SUNFLOWER HYBRIDS

Abstract

With the purpose of determining the influence of weather conditions on the yield components of sunflower, the results of three-year field trials are analysed in the paper. In the trials sown in Osijek in 2013, 2014 and 2015, there were 15 sunflower hybrids: two foreign hybrids and 13 hybrid combinations of the Agricultural Institute Osijek. In the period before sowing (January – March), the highest amount of precipitation was in 2013 (213.1 mm), then in 2015 (167.9 mm), and the lowest in 2014 (109.5 mm). In the growing period (April – September), the highest amount of precipitation (487.3 mm) was in 2014, 475.7 mm in 2013, and in 2015 it was the lowest (251.6 mm). In 2013, during the growing period, the mean monthly air temperature was 19.1°C, in 2015 19.9°C, and in 2014 18.6°C. Of these years, statistically significant at the P=0.05, the highest value of the analysed traits was recorded in 2013: grain yield of 6.47 t ha-1, oil content 51.69% and oil yield 3.05 t ha-1. Grain yield, oil content and oil yield were lower in 2015, and the lowest in 2014. Matej, a newly recognized sunflower hybrid of the Agricultural Institute Osijek had the highest values of grain and oil yield (6.95 and 3.39 t ha-1), and by its oil content of 53.44%, it was in the third place. For high grain and oil yields of sunflower, in addition to the optimal air temperature, the amount and distribution of precipitation before and also during the growing season are very important.