Impactul precipitațiilor atmosferice asupra productivității culturii de floarea-soarelui

The regime of atmospheric precipitation is one of the most important factors in determining sunflower harvest. Besides the sum of precipitation, an important role in sunflower development is also played by the annual distribution of precipitation amounts. The purpose of this study is to determine the impact of atmospheric precipitation on the sunflower productivity. Research objectives consist in identifying the correlations between sunflower harvest and precipitation, as well as identifying the period of the year when the recorded precipitation has a greater impact on crop productivity. In order to identify the periods when precipitation influences the production of sunflower seeds, the data on harvest and precipitation in 2015-2020 for 21 hybrids from five stations of the State Commission for Plant Variety Testing, located in different regions of the country were analyzed. Based on the correlation degree between the two variables, it was established that the precipitation recorded in the growing season (April - September) explains over 55% of the yield variability, while the precipitation recorded in the period June-July explains over 57% of the variability. Territorial distribution of precipitation in summer is very fragmentary. Although, as a rule, higher yields were recorded in the north and center of the country, there were also recorded situations when the distribution of precipitation during the year resulted in higher yield values in the south of the country.