Effect of some herbicides on the productivity of sunflower hybrid Velko
Zornitsa Petrova • Galin Georgiev • Nina Nenova
Dobrudzha Agricultural Institute - General Toshevo, 9521, General Toshevo, Bulgaria
Резюме
The investigations were carried out during 2016–2017 at Dobrudzha Agricultural
Institute – General Toshevo (DAI). The aim of this investigation was to determine the
effect of the treatment with herbicides on the productivity in sunflower hybrid Velko.
The following herbicides combinations were used: pendimetalin (450 ml)+linuron
(300 ml); linuron (300 ml) + pendimetalin (450 ml); metolachlor+terbutilazin (350
ml)+kletodim (160 ml); petoxamide (300 ml) + linuron (300 ml). The herbicides
were applied at stage 01 (BBCH), and pendimetalin (450 ml) and kletodim (160
ml) at stage 12-14 (BBCH) on sunflower hybrid ”Velko”. The herbicide effect was
determined by the quantitative weight method and evaluated by the EWRS scale.
These were the followed parameters: plant height (cm), head diameter (cm), weight
of seeds per plant (g), 1000 seeds weight (g) and oil content of seed (%). In 2016,
highest productivity was realized in the variant with petoxamide (300 ml)+linuron
(300 ml). The decrease of yield according to the untreated check variant was lowest
– with 5.1%. In 2017, metolachlor+terbutilazin (350 ml) + kletodim (160 ml) was
the variant with highest productivity and lowest decrease of yield – with 16.2%. Strong positive correlation was established between the parameters head diameter
and weight of seeds per plant (r = 0.916).
Key words: Herbicides, Productivity, Structural elements of yield, Sunflower,
Weeds.
