Effects of crop densities and nitrogen fertilizing on the maize ear length, number of kernel rows and seed size

The effects of the crop density and nitrogen rates on the ear length, number of kernel rows and the 1000-kernel weight were observed in this study. The four-replicate tow-year experiment was set up according to the completely randomized block design on the chernozem type of soil that had been intensively fertilized intensively by organic and mineral fertilisers for many years. The study encompassed the four nitrogen rates (90-240 kg ha-1) and four crop densities (49,300-75,200 plants ha-1). The obtained results show that the 1000-kernel weight, as well as, the ear length, mostly declined by the increase of both crop density and nitrogen rates (up to a certain level). The increasing crop densities and applied nitrogen rates did not affect the number of kernel rows. Istraživan je uticaj gustine useva i količine azota na dužinu klipa, broj redova i apsolutnu masu zrna kukuruza. Ogled je izveden na černozemu dugo godina intenzivno đubrenim organskim i mineralnim đubrivima po blok sistemu sa potpuno slučajnim rasporedom varijanti u četiri ponavljanja. Istraživanja su trajala dve godine, a obuhvaćena su četiri nivoa azota (90-240 kg/ha) i četiri gustine useva (49.300-75.200 biljaka po hektaru). Rezultati dvogodišnjih istraživanja pokazuju da sa povećanjem gustine, vrednosti apsolutne mase i dužine klipa uglavnom opadaju, a sa povećanjem količine azota blago rastu do određene granice. Na broj redova zrna uticaj rastućih gustina i dodatog azota nema uticaja.