V. Kuneva1*, R. Bazitov2, A. Stoyanova3

1Department of Mathematics, Informatics and Physics, Faculty of Economics, Аgricultural University, Plovdiv, Bulgaria 2Agricultural Institute, 6000 Stara Zagora, Bulgaria
3Department of of Plant Production, Faculty of Agriculture, Thracian University, 6000 Stara Zagora, Bulgaria

(Manuscript received 1 May 2016; accepted for publication 24 June 2016)

Abstract. The aim of the development is (through two-way dispersion analysis – ANOVA) to study the impact of the factors “year characteristics” and “fertilization levels” on the separate biometric indicators for wheat: ear length (cm), ear-bearing stems (cm), number of grains per ear (num.), grain weight per ear (g) and mass of 1000 grains (g). Data for the yield and its structural elements were used. They were obtained through a field experiment conducted in the period 2009 – 2011, on a meadow-cinnamon soil in the experimental field at Agricultural Institute – Stara Zagora. With high degree of reliability the impact of the examined factors and their interaction on the following indicators was statistically proven: length of wheat-ear (cm), ear-bearing stems (cm), number of grains per ear (N), grain weight per ear (g), mass of 1000 grains (g). The strongest impact on the given factors has the factor “fertilization levels” for the indicator “ear- bearing stems” (96%).