Masa zrna po klasu linija dvoredog ječma (HordeumVulgare l. ) u zavisnosti od đubrenja azotom

Kernel weight per spike in two-rowed barley is the main determinant of grain yield. Variability of kernel weight spike-1 was studied in three barley genotypes: G-3033, G-3021 and G-3070, grown over two years under four mineral nitrogen fertilization treatments, 0, 20, 40 and 60 kg N ha-1. The experiment was set up as a randomized block design in three replications. Kernel weight per spike significantly differed across the lines in both years regardless of N application rate. Increased nitrogen rates led to an increase in kernel weight per spike up to 40 kg N ha-1 in the first year, whereas the highest values for kernel weight per spike in the second year were obtained at 60 kg ha-1 N. The proportion of total phenotypic variability for kernel weight per spike was largely attributed to mineral nitrogen fertilization, considerably less to line and negligibly to the line x nitrogen interaction, suggesting that the value of the trait is significantly dependent on the cultural operations used.Masa zrna po klasu kod dvoredog ječma je komponenta prinosa koja u najvećoj meri određuje prinos zrna. U dvogodišnjem periodu analizirana je varijabilnost mase zrna po klasu kod tri linije ozimog dvoredog ječma: G-3033, G-3021 i G-3070, pri četiri nivoa ishrane mineralnim azotom: 0, 20, 40 and 60 kg N ha-1. Masa zrna po klasu se značajno razlikovala kod linija u obe godine nezavisno od nivoa primenjenog N. Povećane doze azota delovale su na povećanje mase zrna po klasu do nivoa 40 kg ha-1 N , dok je u drugoj godini najveća masa zrna po klasu zabeležena na tretmanu 60 kg ha-1 N. U ukupnoj fenotipskoj variajbilnosti za masu zrna po klasu najveći udeo pripadao je mineralnoj ishrani azotom, znatno manji liniji i neznatan interakciji linija x azot, što ukazuje da vrednost ove osobine u najvećoj meri zavisi od primenjene agrotehnike