Department of Plant Production, Faculty of Manufacturing Engineering and Technologies, Technical University of Varna, 1 Studentska str., 9010 Varna, Bulgaria
(Manuscript received 5 September 2020; accepted for publication 16 January 2021)
Abstract. The main purpose of sunflower breeding requires the developing of high-yielding hybrid varieties with broad ecological plasticity that would guarantee the stability of the yield and the quality of the production from them. This investigation involved 10 experimental F1 hybrid combinations developed with the participation of double haploid fertility restorer lines (DHR) obtained through the method of gamma-induced parthenogenesis in combination with embryo culture. The aim of the investigation was to study the productivity and quality of the seeds from the new experimental sunflower hybrid varieties with a view of their future use in practice. The experimental work included years 2014 and 2015, which were significantly different with regard to the climatic conditions. The experiments were carried out in the experimental field and the laboratory of the Technical University in Varna. The hybrid combinations were assessed according to the main parameters of sunflower productivity, namely seed yield (kg/ha) and oil yield (kg/ha), as well as according to the main quality parameter of sunflower seeds – oil percent in seed. Under the conditions of this investigation, the analysis of the results showed that the genotype potential of the hybrids was determining for the seed and oil yield; a relatively high effect of the year conditions was also established for the parameter oil yield. The percent of oil in seeds was determined on the basis of the genotype, and the effect of the year was considerably lower. Summing up the results from the testing of the experimental hybrids, it can be pointed out that three of the studied hybrid combinations (3607A х 112DHR, 3607A х 123DHR and 3607A х 167DHR) realized good production potential under variable agro-meteorological conditions and can find future realization in practice.