Dobrudzha Agricultural Institute - General Toshevo, 9521, General Toshevo
Резюме
During the period 2014-2018, the influence of the precursor and mineral fertilization
on the variation of productive characteristics of the Kalina and Kosara common
wheat varieties was studied. The study was conducted in the Experimental Field
of the Dobrudzha Agricultural Institute - General Toshevo (Haplic Chernozems).
The varieties were grown after 4 precursors (winter rape, spring peas, sunflower
seeds and corn for the grain) and 4 levels of nutrition differentiated by nitrogen
norms depending on the precursor. After spring peas, 3, 6 and 9 kg N / dka were used, and after the other predecessors 6, 12 and 18 kg N / dka were used. With the
exception of the control variant, which reflects the natural fertility of the site, all
fertilizer variants have a background fertilization of 6 kg P2O5 / dka and 6 kg K2O /
dka. The duration of the experiment, covering years with a diverse combination of
meteorological elements, distinguished Kosara with a higher average productivity
compared to Kalina - by 4.39%. Despite this fact, the Kalina variety has higher
values of the agronomic effect (by 7.25%) and the effect of the 1-st nitrogen - by
41.87% compared to the Kosara variety. The influence of mineral fertilization on
the tested indicators is variable due to the strong dependence of the yield on the
meteorological situation. On average over the period, the same for the precursors
tested at a ratio of N: P: K = 3:1:1 was most favorable for both varieties. Of the
precursors tested, rapeseed has the most pronounced adverse effect on productivity
and its characteristics. The Kalina variety was found to have a larger and heavier
grain compared to the Kosara variety, by 14.42% and 1.20%, respectively. There
are also significant correlations between the effect of 1-st nitrogen, agronomic effect
and productivity. For the Kosara variety the values of the correlation coefficients
are higher than those of the Kalina variety.
