Lucerka i silažni kukuruz predstavljaju najvažnija kabasta hraniva u Srbiji i svetu. Predstavljaju osnovni deo obroka preživara za zadovoljenje energetskih zahteva životinja, kao i osnovni izvor minerala u ishrani. Biofortifikacija krmnog bilja, odnosno đubrenje mikroelementima je jedan od načina pomoću koga može da se u biljkama postigne veći sadržaj neophodnih elemanata za stoku, prvenstveno Se i Zn. Iz tog razloga, cilj istraživanja je bio ispitivanje uticaja đubrenja N i mikroelementima na prinos i mineralni sastav lucerke i silažnog kukuruza, odnosno da se utvrdi u kojoj meri đubrenje N, Se, Zn i Cu utiče na sadržaj neophodnih elemenata u ishrani stoke preživara. Poljski ogled sa lucerkom (2014-2016) je postavljen kao jednofaktorijalni po metodi blok sistema sa slučajnim rasporedom tretmana. U ogledu je ispitivan uticaj sledećih folijarnih tretmana: kontrola bez đubrenja; Se u dve doze (5 i 10 g Se ha-1); Zn u dve doze (0,5 i 1 kg Zn ha-1), 2% rastvor Cu i Zn i Se u kombinaciji (0,5 kg Zn ha-1 i 10 g Se ha-1). Ogled sa kukuruzom (2014-2016) je postavljen kao dvofaktorijalni metodom podeljenih parcela, pri čemu prvi faktor predstavlja đubrenje N a drugi đubrenje mikroelementima. Glavne parcele ogleda predstavlja đubrenje N u sledećim dozama: 0; 120; 180 i 240 kg N ha-1. Na podparcelama ogleda izvršeno je đubrenje mikroelementima u sledećim varijantama: kontrola bez primene mikroelemenata; 10 g Se ha-1; 1,5 kg Zn ha-1 i 1,5 kg Zn ha-1 u kombinaciji sa 7% rastvorom uree. Tokom tri godine izvođenja ogleda vršeno je merenje prinosa, dok je sadržaj sirovih proteina i pojedinih makro (P, K, Ca, Mg, S) i mikroelemenata (Se, Zn, Mo, Fe, Cu, Mn) analiziran tokom prve dve godine ogleda. Rezultati su pokazali da đubrenje N povećava prinos zelene mase silažnog kukuruza, kao i sadržaj sirovih proteina, Zn, Cu i Mn u suvoj masi. Folijarna primena Se nije imala uticaja na prinos lucerke i silažnog kukurza, ali je pozitivno uticala na sadržaj Se u biljci. Sa obe primenjen doze Se, u lucerki je postignut neophodan nivo Se za ishranu goveda, dok đubrenjem sa 10 g Se ha-1 u silažnom kukuruzu nije postignut taj nivo. Primenom 1 kg Zn ha-1 u slučaju lucerke, odnosno 1,5 kg Zn ha-1 u slučaju silažnog kukuruza, neophodan nivo u ishrani stoke je postignut samo u toku jedne godine. Folijarna primena Zn i uree u kombinaciji se pokazala efikasnijom u povećanju sadržaja u biljci, akumulaciji po hektaru i usvajanja Zn u poređenju kada se istiu uslovima bez navodnjavanja, međutim,5element primeni samostalno. Đubrenje Cu je očekivano povećalo njegov sadržaj u biljci, ali godini sa ređim sklopom biljka, postignuti sadržaj Cu biljkama je bio iznad maksimalno dozvoljene koncentracije za ishranu goveda. S obzirom da je krajnji cilj proizvodnje krmnog bilja visoki prinosi dobrog kvaliteta, đubrenje N doprinosi ovakvim rezultatima. Folijarno đubrenje Se, Zn i Cu predstavlja važnu agrotehničku meru za povećanje sadržaja ovih elemenata u lucerki i silažnom kukuruzu gajenim na slaboalkalnom zemljištau uslovima bez navodnjavanja, međutim, u slučaju Zn, potrebno je ispitati uticaj većih doza., Alfalfa and silage maize represent the most important forages in Serbia and the world. They are an essential part of a meal for ruminants to meet their energy requirements, and constitute the basic source of minerals in their diet. Biofortification of forage crops, i.e. fertilization with microelements, is one of the ways how a higher content of essential elements for livestock, primarily Se and Zn, can be achieved in plants. For this reason, the aim of the study was to investigate the effect of N and microelements fertilization on the yield and mineral composition of alfalfa and silage maize, and to determine the extent to which fertilization with N, Se, Zn, and Cu affects the content of essential elements in the diet of ruminant cattle. The field experiment with alfalfa (2014-2016) was set up using a single-factor randomized block design. The effect of the following foliar treatments was investigated: control without fertilization; Se in two doses (5 and 10 g Se ha-1); Zn in two doses (0.5 and 1 kg Zn ha-1), 2% solution of Cu and Zn and Se in combination (0.5 kg Zn ha-1 and 10 g Se ha-1). The silage maize experiment (2014-2016) was set up as a two-factorial split-plot design, with the first factor being N fertilization and the second microelements fertilization. The main plots of the experiment were treated with N fertilizer in the following doses: 0; 120; 180 and 240 kg N ha-1. The sub-plots of the experiment were fertilized with microelements in the following variants: control without application of microelements; 10 g Se ha-1; 1.5 kg Zn ha-1 and 1.5 kg Zn ha-1 in combination with 7% urea solution. Yield measurements were recorded during the three years of the experiment, while the content of crude protein and individual macro (P, K, Ca, Mg, S) and microelements (Se, Zn, Mo, Fe, Cu, Mn) were analyzed during the first two years of the experiment. The results showed that N fertilization increased the green mass yield of silage maize, as well as the content of crude protein, Zn, Cu and Mn in the dry mass. Foliar application of Se had no effect on the yield of alfalfa and silage maize but had a positive effect on Se content in the plant. With both doses of applied Se, the optimal level of Se for cattle feeding was reached in alfalfa, while fertilizing with 10 g of Se ha-1 in silage maize did not reach that level. By applying 1 kg of Zn ha-1 in the case of alfalfa, or 1.5 kg of Zn ha-1 in the8case of silage maize, the optimal level in livestock nutrition was reached only in one year. When compared with the same element alone, foliar application of Zn and urea in combination proved to be more effective in increasing plant content, accumulation per hectare, and Zn uptake. As expected, fertilization with Cu increased its content in the plant, but in the year with a lower plant density, the achieved Cu content in plants was above the maximum allowable concentration for cattle nutrition. Given that the ultimate goal of forage production is high yields of good quality, fertilizing with N contributes to these results. Foliar fertilization with Se, Zn, and Cu presents an important agrotechnical measure for increasing the content of these elements in alfalfa and silage maize grown on low-alkaline soil under rainfed conditions; however, in the case of Zn, the impact of higher doses requires further research