INFLUENCE OF FERTILIZATION WITH ORGANIC AND MINERAL FERTILIZERS ON YIELD AND QUALITY OF ITALIAN RYEGRASS AND RED CLOVER MIX

U radu je istraživan utjecaj gnojidbe organskim i mineralnim gnojivima na prinos i kvalitetu smjese talijanskog ljulja i crvene djeteline. Istraživanje je provedeno u 2010. u mjestu Poljanec u Varaždinskoj županiji. Pokus je postavljen po shemi slučajnog bloknog rasporeda u 4 ponavljanja. Varijante gnojidbe su bile sljedeće: bez gnojidbe (G1), gnojidba sa 40 t/ha krutog goveđeg gnoja (zaorano) + prihrana sa 20 000 l/ha gnojnice u proljeće i iza 1. otkosa (G2), gnojidba sa 30 t/ha krutog goveđeg gnoja i 300 kg/ha gnojiva NPK 7-20-30 (zaorano) + prihrana sa 20 000 l/ha gnojnice u proljeće i iza 1. otkosa (G3) i gnojidba sa 350 kg gnojiva NPK 7-20-30 (zaorano) i 150 kg/ha NPK 15-15-15 (pred sjetvu) te 200 kg/ha KAN-a (prihrana) u proljeće i iza 1. otkosa (G4). Djetelinsko travna smjesa sijana je 11. IX. 2009. s udjelom talijanskog ljulja od 20 % (8 kg/ha) sorte Mir i 80 % crvene djeteline (16 kg/ha) sorte Viola. Nakon sjetve je, zbog nedostatka oborina, obavljeno zalijevanje površine s 60 mm vode (4x15 mm). Košena su tri otkosa (26. IV., 9. VI. i 8. VII.). Istraživalo se sljedeće: udio komponenata u smjesi, prinos svježe mase (SVM), suhe tvari (ST) i sirovih proteina (SP) te sadržaj ST, SP, sirovih vlakana (SV), sirovog pepela (SPep), sirove masti (SM) i sirovih nedušičnih ekstraktivnih tvari (S.NET). Udio talijanskog ljulja bio je izrazito visok (u prosjeku 92,7 %), crvene djeteline izrazito nizak (u prosjeku 5,0 %) u sva tri otkosa. Jedino je na G1 varijanti u G2 varijantu bilo manje talijanskog ljulja, a više crvene djeteline. Udio korova bio je izraženiji samo u 1. otkosu (6,4 %). Prinos SVM bio je najviši u 1. otkosu (37,8 t/ha) i padao je do 3. otkosa (26,1; 17,6 t/ha). U prosjeku otkosa, značajno niži prinos SVM bio je na G2 (29,3 t/ha) u odnosu na G2 i G3 (29,3 i 29,6 t/ha) varijante gnojidbe. Ukupni prinos SVM u 3 otkosa bi je značajno veći na G2 (87,9 t/ha) i G4 (88,8 t/ha) u odnosu na G1 (72,2 t/ha) i G3 (77,4 t/ha) varijante gnojidbe. Najniži prinos suhe tvari bio je u 3. otkosu (4,2 t/ha) u odnosu na 1. i 2. otkos (5,8 i 5,8 t/ha). Ukupni prinos STV u 3 otkosa kretao se od 14,8 do 16,8 t/ha. Različite varijante gnojidbe nisu pokazale različito djelovanje na prinos STV niti u prosjeku otkosa niti u ukupnom prinosu 3 otkosa. Prinos SP značajno je opadao od 1. do 3. otkosa (900,3; 704,8; 416,7 kg/ha). Najniži prinos SP bio je na G1 (578,2 kg/ha), a najviši na G4 i G2 (781,9 i 720,2 kg/ha) varijanti gnojidbe. Ukupni prinos SP u 3 otkosa bi je značajno veći na G2 i G4 (16,6 i 16,0 t/ha) u odnosu na G1 i G3 (15,3 i 14,8 t/ha) varijante. S povećanjem rednog broja otkosa rastao je sadržaj ST (16,1; 22,2; 23,6 %), SV (23,1; 27,7; 32,5 %) i S.NET (76,9; 102,8 i 109,3 g/kg ST), a opadao sadržaj SP (15,5; 12,2; 10,0 %), SPep (10,5 i 10,8; 8,7 %) i SM (4,0; 3,0 i 2,6 %). Varijante gnojidbe, u prosjeku otkosa, nisu utjecale na sadržaj SV, SPep i SM, a značajnije razlike su nastale kod sadržaja SP gdje je na G4 utvrđen značajno viši sadržaj SP (14,3 %) u odnosu na ostale tri varijante (11,2 do 12,5 %) te za S.NET gdje je na G1 utvrđen značajno niži sadržaj NET u odnosu na G2 i G4 (88,3-92,4 g/kg ST). Može se zaključiti da se gnojidbom isključivo mineralnim gnojivima (G4) u usporedbi s gnojidbom isključivo organskim gnojivima (G2) prinosi i kvaliteta krme nisu značajno razlikovali.The paper presents the research regarding the influence of fertilization with organic and mineral fertilizers on yield and quality of Italian ryegrass and red clover mix. The research was carried out in 2010 in Poljanec, Varaždin County. The trial was set according to the scheme of random block order in 4 repetitions. Fertilization variants were as follows: no fertilization (G1), fertilization with 40 t/ha of solid cattle manure (plowed) + additional nutrients from 20 000 l/ha of slurry in spring and after the first cut (G2), fertilization with 30 t/ha of solid cattle manure and 300 kg/ha of NPK 7-20-30 fertilizer (plowed) + additional nutrients from 20 000 l/ha of slurry in spring and after the first cut (G3) and fertilization with 350 kg of NPK 7-20-30 fertilizer (plowed) and 150 kg/ha of NPK 15-15-15 fertilizer (prior to seeding) and 200 kg/ha KAN-a (additional nutrients) in spring and after the first cut (G4). Clover grass mix was sown on 11. November 2009 with proportion of Italian ryegrass amounting to 20 % (8 kg ha-1) of the Mir cultivar and 80 % of red clover (16 kg ha-1), Viola cultivar. After sowing, due to lack of rain, the surface area was watered with 60 mm of water (4x15 mm). There were three cuts (26. April, 9. June and 8. July). The research comprised the following parameters: percentage of components in the mix, yield of fresh mass (FM), dry matter (DM) and crude proteins (CP) as well as the content of DM, CP, crude fibers (CF), crude ashes (CA), crude fat (CF) and crude non-nitrogen extractive matter (C.NEM). The percentage of the Italian Ryegrass was distinctively high (on average 92.7 %), whereas the percentage of red clover was very low (on average 5.0 %) in all three cuts. Only the G1 and G2 variants indicated smaller levels of the Italian ryegrass and higher levels of red clover. The percentage of weed was more prominent only in the first cut (6.4 %). The yield of FM was the highest in the first cut (37.8 t/ha) and gradually dropped until the third cut (26.1; 17.6 t ha-1). Based on the mean values of the cut, G2 indicated a significantly lower yield of FM (29.3 t ha-1) in comparison with G2 and G3 (29.3 and 29.6 t ha-1) fertilization variants. The total yield of FM in all three cuts was significantly higher in G2 (87.9 t ha-1) and G4 (88.8 t ha-1) in comparison with G1 (72.2 t ha-1) and G3 (77.4 t ha-1) fertilization variants. The lowest yield of DM was observed in the third cut (4.2 t/ha) in relation to the first and the second cut (5.8 and 5.8 t ha-1). Total yield of DM in all three cuts moved from 14.8 to 16.8 t ha-1. Different fertilization variants didn't indicate different influence on the yield of DM, neither in the mean values of the cut nor in the total yield of all three cuts. The yield of CP dropped significantly from the first to the third cut (900.3; 704.8; 416.7 kg ha-1). The lowest yield of CP was in G1 (578.2 kg ha-1), and the highest in G4 and G2 (781.9 and 720.2 kg ha-1) fertilization variants. Total yield of CP in all three cuts was significantly higher in G2 and G4 (16.6 and 16.0 t ha-1) in comparison with G1 and G3 (15.3 and 14.8 t ha-1) variants. The increase in the number of cuts was accompanied with the increase of DM content (16.1; 22.2; 23.6 %), CF (23.1; 27.7; 32.5 %) and C.NEM (76.9; 102.8 and 109.3 g kg-1 ST), and decrease of CP content (15.5; 12.2; 10.0 %), CA (10.5 and 10.8; 8.7 %) and CF (4.0; 3.0 and 2.6 %). Regarding the mean values of individual cuts, fertilization variants didn't influence the content of CF, CA and CF, whereas more significant differences were observed with the content of CP, since the CP content for G4 was significantly higher (14.3 %) in comparison with the remaining three variants (11.2 to 12.5 %), as well as for C.NEM where the NEM content observed with G1 was significantly lower in comparison with G2 and G4 (88.3-92.4 g kg-1 ST). It can be concluded that fertilization with mineral fertilizers (G4) in comparison with fertilization with organic fertilizers (G2) showed no significant differences in yield and quality of fodder crops