A. IVANOVA and N. TSENOV
Dobrudzha Agricultural Institute, BG - 9520, General Toshevo, Bulgaria
IVANOVA, A. and N. TSENOV, 2010. Effect of some agronomy practices on main traits of grain yield in winter wheat varieties of different quality Bulg. J. Agric. Sci., 16: 559-564
The significance of wheat as a major cereal crop constantly provokes the interests to search for means and methods of increasing the productivity and the quality potential of wheat grain. A three-year field trial (2004 2006) analyzed the effect of some main agronomy practices (previous crop and fertilization norm), as well as the specific year conditions on main grain yield traits of 14 common winter wheat varieties. The investigated genotypes were divided into two groups according to their officially registered grain quality. The following traits were studied: grain yield, test weight and 1000 kernel weight, length of main spike, number and weight of grains per spike. The varieties were grown after four previous crops (bean, sunflower, grain maize and fodder maize) and under three nutrition regimes.
The mineral fertilization was applied according to the type of previous crop as follows: N6P6K0 and N10P10K0 after bean, and N10P10K0 and N14P14K0 after the other previous crops, the check variant being N0P0K0. The multifactor analysis of variances showed highest effect of the year on most of the investigated traits (plant height, test weight, length of main spike, number and weight of grains per spike) for the varieties of both group A and group B. Mineral fertilization was the most important agronomy practice for formation of higher grain yield and productive tillers in both groups. Thousand grain weights is a varietal mark; it was affected most by genotype itself. It was found out that the varieties from group B gave higher grain yield, which was on the whole due to the higher grain weight per spike as a result from the combination of more grains of larger size per the spike; although the productive tillering in this group was significantly lower in comparison to group A. The varieties from group A had stems with 2 cm longer, showed significantly higher productive tillering and formed more compact grain of higher quality.