Dobrudzha Agricultural Institute - General Toshevo, 9521, General Toshevo, Bulgaria
Резюме
During 2016–2017 a field experiment was conducted with three new sunflower
hybrids (Vilia, Enigma and Linzi) in the trial field of Dobrudzha Agricultural
Institute. The aim was to determine the effect of the sowing norm and of a set of
foliar fertilizers on the quantitative and qualitative indices of seed yield as a part
of determining the elements forming the optimum agronomy practices for growing
of the above hybrids. The variants of the experiment were the following: 1) check
(untreated); 2) mineral fertilization at norm N60P120K80 (active matter/ha); foliar
fertilization with: 3) Root; 4) Siapton; 5. Lebosol B; 6) Aminosol; 7) Aminosol
mix; 8) Yara Vita Brassitrel pro. The foliar treatment was done by sprinkling the
leaf mass at stage 6-7th pair of leaves. The soil in the experimental field was leached
chernozem (Luvic phaeosem) with 3.30% humus content classified as very suitable
for sunflower growing.
The averaged two-year results for seed yield showed that sunflower hybrid Vilia
realized highest seed yield, regardless of the variants of the experiment, followed
by hybrids Enigma and Linzi. Depending on the crop density (main action of the
factor), hybrid Vilia had a positive response to higher densities, hybrid Enigma
was indifferent, while hybrid Linzi decreased its seed yield with the higher crop
densities. Depending on the tested variants of macro and micro fertilization (main
action of this factor), the results were positive for hybrids Vilia and Enigma, and in hybrid Linzi there was no change in the size of yield. Hybrid Vilia was with the
highest 1000 kernel weight, regardless of the tested variants, flowed by Linzi and
Enigma. Thousand kernel weigh was influenced much more by the crop density
than by the variants of foliar fertilization. The inverse proportional dependence
remained the same, namely 1000 kernel weight decreased with the higher crop
densities. The foliar fertilization with the tested products, considered a main action
of this factor, did not have significant effect on the value of the parameter “1000
kernel weight”. The oil content in the seeds of the hybrids during the investigation
was not influenced significantly by the factors involved in this experiment