Alojzije LALIĆ, Vlado GUBERAC, Dario NOVOSELOVIĆ, Smiljana GORETA, Gvozden DUMIČIĆ, Branimir URLIĆ, Georg DREZNER, Krešimir DVOJKOVIĆ, Ivan ABIČIĆ, Josip KOVAČEVIĆ 46 th Croatian and 6 th International Symposium on Agriculture 596 Učinak dušika i zasušivanja na svojstva biljke kod ozimih sorti ječma Alojzije LALIĆ 1 , Vlado GUBERAC 3 , Dario NOVOSELOVIĆ 1 , Smiljana GORETA 2 , Gvozden DUMIČIĆ 2 , Branimir URLIĆ 2 , Georg DREZNER 1 , Krešimir DVOJKOVIĆ 1 , Ivan ABIČIĆ 1 , Josip KOVAČEVIĆ 1 1 Poljoprivredni institut Osijek, Južno predgrađe 17, 31000 Osijek, Hrvatska, (e-mail: alojzije.lalic@poljinos.hr) 2 Institut za jadranske kulture i melioraciju krša, Put Duilova 11, 21000 Split, Hrvatska 3 Sveučilište Josipa Jurja Strossmayera u Osijeku, Poljoprivredni fakultet u Osijeku, Trg Svetog Trojstva 3, 31000 Osijek, Hrvatska Sažetak Cilj rada bio je istražiti učinak sorte, vodnog stresa i ishrane dušikom (N) na morfološka i gospodarska svojstva ječma. Istraživanja ukazuju na suodnos vodnog stresa, ishrane dušikom (razine = 5 mmol/L N; N10 = 10 mmol/L N; N15 = 15 mmol/L N) i sorte. Vodni stres je imao značajan negativan učinak na broj vlati, broj listova, količinu klorofila, ukupnu masu biljke i lista. Ustanovljen je pozitivan učinak ishrane u uvjetima stresa, iako je učinak ishrane na istraživana svojstva jači u uvjetima uzgoja bez vodnoga stresa. Utvrđeno je da sorte Vanessa i Spartak pod utjecajem vodnog stresa najbolje održavaju osmotski potencijal i relativni sadržaj vode (RWC) u biljci, pokazujući najmanje razlike između najznačajnijih morfoloških svojstava u uvjetima vodnog stresa i bez stresa. Ključne riječi: ječam, vodni stres, ishrana, dušik, sorta Effect of nitrogen and water deficiency on the properties of plants in the winter barley varieties Abstract The aim of the present study was to investigate the effect of variety, water stress and nitrogen (N) nutrition on agronomic and morphological traits of barley. Results indicate the relationship between water stress, nitrogen nutrition (level N5, N10, N15) and variety. Water stress had a significant negative effect on the number of tillers, number of leaves, the amount of chlorophyll, total plant and leaf weight. There was a positive effect of nutrition in stress conditions, although the effect of nutrition on traits was stronger in growing conditions without water stress. It was found that varieties Vanessa and Spartak influenced by water stress performed better compared to other varieties in maintaining osmotic potential and RWC in plants, showing the lowest differences between the most important morphological traits in water stress and stress-free conditions. Key words: barley, water deficiency, nutrition, N, variety Proceedings. 46 th Croatian and 6 th International Symposium on Agriculture. Opatija. Croatia (596-600) IZVORNI ZNANSTVENI RAD