Lubomir IVANOV, Siika PAVLOVA, Ivelina VENKOVA
Abstract. During the period 2007– 2009 a field experiment was conducted at the IASS “Obraztsov chiflik”– Rousse for determination of the accumulation of dry matter in three maize hybrids according to FAO: Clarica–300; Evelina–400 and PR35P12–500. The experiment was conducted in densities 4000, 5000, 6000 and 7000 plants per a da in two configurations of sowing–square and rectangular. The results showed that the tested hybrids accumulated various quantity biomasses depending on the climatic conditions, density and the configuration of the nutritive area. Under conditions of extreme soil and atmospheric drought, hybrid PR35P12 accumulated the highest quality of biomass in square configurations 50/50 cm and 44.7/44.7 cm and in the rectangular–70/35.7 cm and 70/28.6 cm, and hybrid Clarica–in the densities of 50/50 cm and 70/35.7 cm. Only hybrid Evelina accumulated more dry matter in the rectangular configurations of 70/35.7 cm and 70/28.6 cm.
Keywords: dry matter, density, square and rectangular configurations