THE SHARE OF THE IRRIGATION AND FERTILIZERS APPLICATION IN GRAIN YIELD BUILDING IN 500-600 MATURITY GROUP CORN

Eksperiment je izveden u ekološkim uvjetima Zemun Polja u toku 1976. 1977. i 1978. godine, na slabo karbonatnom černozemu. Zemljište je dobrih fizičkih, kemijskih i mikrobioloških osobina. Eksperiment je bio postavljen po metodi razdjeljenih parcela (Split-plot), kao trofaktorijalni u tri ponavljanja. Prvi faktor je bila voda: V₁ Kontrola (bez navodnjavanja) ; V₂ Navodnjavanje umjetnom kišom. Vrijeme zalijevanja utvrđivano je na osnovu praćenja i gravitmetrijskog određivanja sadržaja vode u zemljišnom sloju od 70 cm u intervalu od 7 dana. Navodnjavanjem je održavana vlažnost ovog zemljišnog sloja na nivu 70% od O.K.K. Drugi faktor je bilo gnojenje: G₁ Kontrola (bez gnojenja) G₂ Gnojenje sa N-160 kg/ha, P₂O₅ - 110 kg/ha i K₂O – 64 kg/ha. Cijelokupna količina PK hraniva dana je u jesen prilikom duboke obrade zemljišta. Jedna polovina dušićnih gnojiva dana je pred predsjetvenu pripremu zemljišta a ostali dio je dan prilikom prihranjivanja. Treći faktor bili su hibridi FAO grupe zrenja 500-600 čija je dužina vegetacije oko 130 dana: H₁ ZP SC 46A, H₂ ZP SC 48A, H₃ ZP SC 58C, H₄ ZP SC 55. Na osnovu trogodišnjih rezultata proučavanja uloge vode i gnojiva na formiranje prinosa kukuruza, može se zaključiti: Vodni režim zemljišta po proučavanim godinama i fazama porasta kukuruza bio je neujednačen, te su intervencije s navodnjavanjem uslijedile po različitim fazama. U svakoj godini bila su primjenjena po dva zalijevanja. Norme zalijevanja kretale su se od 400 do 700 m³ vode po hektaru, a norme navodnjavanja od 900 m³/ha u 1978. godini do 1100 m³/ha u 1977.godini. Proučavani faktori nisu imali značajnijeg utjecaja na debljinu klipa, broj redova na klipu i postotak oklaska, dok se na dužinu klipa ispoljio utjecaj navodnjavanja i gnojenja. Obezbjeđenost kukuruza vodom i hranivima imala je utjecaja na smanjenje postotka jalovih biljaka, dok se na postotak poleglih biljaka taj utjecaj nije ispoljio. Također, proučavani faktori imali su značajnijeg utjecaja na težinu zrna po klipu i težinu 1000 zrna. Ostvareni prinosi pokazali su da su bili u određenom stupnju uslovljeni gnojenjem, navodnjavanjem i hibridom. Kombinacija s gnojenjenjem i navodnjavanjem dala je za 36,6% veći prinos od kombinacije koja je bila bez gnojenja i bez navodnjavanja. Također, ova kombinacija dala je i ujednaćeniji prinos, tijekom proučavanih godina. Navodnjavanje je u prosijeku doprinijelo povećanju prinosa za 13,85%, a gnojenje za 23,76%

THE INFLUENCE OF SEVERAL PRODUCTION FACTORS ON SHOOTS APPEARANCE AND ON GRAIN YIELD IN CORN

Ispitivanje je izvršeno na Oglednom polju Instituta za kukuruz u Zemun Polju, na zemljištu tipa černozem. Naš doprinos ovoj problematici je pokušaj da se ustanovi kakav uticaj ispoljavaju gnojiva, gustina i meteorološki uvjeti godine na formiranje zaperaka. Istovremeno ustanovili smo i uticaj navedenih faktora kao i vremena zakidanja zaperaka na prinos kukuruza. Gnjojenje ogleda izvršeno je kompleksnim (4:11:9) i dušičnim (KAN) gnojivom (N-25%). Ispitivane su sljedeće varijante gnojiva: (G-1) kontrola negnojeno (G-2) 240 kg/ha N - 90, P₂O₅ - 80, K₂O - 70 kg/ha (G-3) 360 kg/ha N - 135, P₂O₅ - 120, K₂O - 105 ka/ha (G-4) 240 kg/ha (isto kao G-2) + 20 t stajnjaka/ha Ispitivane gustine sklopa bile su sljedeće: (G-1) 30.486 biljaka/ha - 80x82+2 biljke/kućici (G-2) 35.210 biljaka/ha - 80x71+2 biljke/kućici (G-3) 40.322 biljaka/ha - 80x62+2 biljke/kućici (G-4) 50.000 biljaka/ha - 80x50+2 biljke/kućici Zakidanje zaperaka izvršeno je u sljedećim fazama rasta i razvića biljke kukuruza: (V-1) u fazi 6 - 7 listova (V-2) u fazi 9 - 11 listova (V-3) u fazi metličenja (V-4) kontrola (zaperci nisu zakinuti) Na osnovu naših ispitivanja mogu se izvesti sljedeći zaključci: Na veći ili manji procenat pojavljivanja zaperaka utjecale su meteorološke prilike godine. U odnosu na negnojenu varijantu, mineralno a još više mineralno stajsko gnojivo utjecale su na pojavu većeg postotka zaperaka. Postotak zaperaka smanjivao se s povećanjem gustine sklopa. Vrijeme zakidanja zaperaka utjecalo je na prinos u signifikantno opravdani razlikama u godini koja je u drugoj polovini vegetacije kukuruza imala veliki nedostatak padalina (1967). U trogodišnjem prosjeku prinos je veći za 5,51% ako su zaperci uklonjeni u fazi biljaka 6-7 listova prema prinosu biljaka gdje zapetci nisu uklonjeni. I kod intenzivne pojave zapetaka uklanjanje istih u kasnijim fazama rasta i razvitka biljaka nema opravdanja pošto ne utječe na prinos. Na bogatom černozemu negnojene varijante, prinos je gotovo isti ako su zaperci-uklonjeni sa varijantom gnojenja neuklonjenih zaperaka. U većim gustinama sklopa gde je manji postotak zaperaka iste nije potrebno uklanjati pošto ne utječu na smanjenje prinosa.The investigations were conducted on the Experimental Field of the Maize Research Institute Zemun Polje on a chernozem type of soil. As a contribution to this problematics we made an attempt to establish the effect of fertilizers, plant population and current meteorological conditions on tillering. We have also investigated the effects of the quoted factors, as well as the time of removing tillers, on maize yield. In these trials complex (4:11:9) and nitrogen (KAN) fertilizers (N-25%) were applied. The following fertilizer variants were investigated: (DJ-1) control nonfertilized (DJ-2) 240 kg/ha N - 90, P₂O₅ - 80, K₂O - 70 kg/ha (DJ-3) 360 kg/ha N - 135, P₂O₅ - 120, K₂O - 105 kg/ha (DJ-4) 240 kg/ha (the same as DJ-2) + 20t manure/ha The investigated plant populations were the following: (G-1) 30,486 plants/ha - 80x82+2 plants/hill (G-2) 35,210 plants/ha - 80x71+2 plants/hill (G-3) 40,322 plants/ha - 80x62+2 plants/hill (G-4) 50,000 plants/ha - 80x50+2 plants/hill The removing of tillers was carried out during the following stages of development of the maize plant: (V-1) during the 6-7 leaf stage (V-2) during the 9-11 leaf stage (V-3) during taseling (V-4) control (tillers were not removed) Based on our investigations, the following conclusions can be drawn: 1. A higher or lower percentage of tillering was affected by current meteoroogical conditions. 2. In comparison to the nonfertilized variant, mineral fertilizers, but even more so mineral fertilizers + stable manure caused a higher parcentage of tillering. 3. The percentage of tillering incressed with increased with increasing plant population. 4. The time of removing tillers affected yields significantly in the year (1967) in which there had a shortage in rainfall during the second half of the maize vegetation period. 5. A three-year average showed that yields were higher by 5,56% provided the tillers were removed during the 6-7 leaf stage, as compared to yields of plants in which tillers were not removed. 6. The removing of tillers in the later stages of development to the plants, was found not to be justified as it had no effect on yields. 7. As for the monfertilized variant on the rich chernozem type of soil, the zield was almost the same as when the tillers were removed in the variant of fertilizing unremoved tillers. 8. At higher plant populations where the percentage of tillens is low, it is not necessary to remove tillers as these do not cause a decrease in yield

Yields of ZP sweet maize hybrids in dependence on sowing densities

Sweet maize differs from maize of standard grain quality by many important traits that affect the ear appearance, and especially by traits controlling taste. The ear appearance trait encompasses the kernel row number, configuration, row pattern (direction and arrangement), seed set, kernel width and depth, ear shape and size. The quality of immature kernels is controlled by genes by which sweet maize differs from common maize. In order to obtain high-ranking and high-quality yields, it is necessary to provide the most suitable cropping practices for sweet maize hybrids developed at the Maize Research Institute, Zemun Polje. The adequate sowing density is one of more important elements of correct cropping practices. The objective of the present study was to determine the effect of four sowing densities in four ZP sweet maize hybrids of different FAO maturity groups on ear qualitative traits and yields obtained on chernozem type of soil in Zemun Polje. The observed traits of sweet maize (ear length, kernel row number, number of kernels per row, yield and shelling percentage) significantly varied over years. The higher sowing density was the higher yield of sweet maize was, hence the highest ear yield of 9.67 t ha-1 , on the average for all four hybrids, was recorded at the highest sowing density of 70,000 plants ha-1. The highest yield was detected in the hybrid ZP 424su. The highest shelling percentage (67.81%) was found in the hybrid ZP 521su at the sowing density of 60,000 plants ha-1. Generally, it can be stated that sweet maize hybrids of a shorter growing season (FAO 400) could be cultivated up to 70,000 plants ha-1, while those of a longer growing season (FAO 500) could be grown up to 60,000 plants ha-1. In such a way, the most favorable parameters of yields and the highest yields can be obtained

Interakcija genotipa i faktora spoljne sredine na ekspresiju heterozisa kod kukuruza

The three-year studies on effects of irrigation and sowing densities were carried out on chernozem at Zemun Polje in the period 1998-2000. The four-replicate trial was set up according to the split-plot design. Six ZP maize hybrids (ZP 360, ZP 539, ZP 580, ZP 633, ZP 677. and ZP 704) were sown in seven densities (40,816, 50,125, 59,523, 69,686, 79,365, 89,286 and 98,522 plants ha-1) under both, irrigation and rainfed conditions. Obtained results indicate that yields of hybrids under irrigation conditions were lower at sowing densities up to 50.000 plants ha-1 (40,816 and 50,125). The hybrid ZP 539 had similar yields (13.44-13.93 t ha-1) at densities ranging from 60,000 to 100,000 plants ha-1. The highest yields of hybrids ZP 360 and ZO 580 were achieved with the densities of 80,000, 90,000 and 100,000 plants ha-1. The hybrid ZP 633 had the highest yields at the densities of 60,000-90,000 plants ha-1, while the highest yields of the hybrids ZP 677 and ZP 704 were achieved with densities of 60,000-100,000 plants ha-1. The curvilinear regression was determined by the analysis of dependence of achieved yields of maize hybrids on sowing densities. The following maximum yields could be expected under irrigation conditions: ZP 360 - 14.19 t ha-1 with the sowing density of 93,500 plants ha-1; ZP 539 - 14.03 t ha-1 with the sowing density of 78,500 plants ha-1; ZP 580 - 14.41 t ha-1 with the sowing density of 95,700 plants ha-1; ZP 633 - 13.64 t ha-1 with the sowing density of 80,000 plants ha-1: ZP 677 - 13.31 t ha-1 with the sowing density of 92,250 plants ha-1 and ZP 704 - 14.33 t ha-1 with the sowing density of 84,111 plants ha-1.Trogodišnja proučavanja uticaja navodnjavanja i gustine setve obavljena su u periodu 1998-2000 u Zemun Polju na černozemu. Ogled je postavljen po split-plot metodi, u četiri ponavljanja. U uslovima sa i bez navodnjavanja, u sedam gustina setve (40816, 50125, 59523, 69686, 79365, 89286 i 98522 plants'ha-1) sejano je šest ZP hibrida kukuruza (ZP 360, ZP 539, ZP 580, ZP 633, ZP 677, ZP 704). Rezultati proučavanja pokazuju da su u navodnjavanju svi hibridi statistički veoma značajno niže prinose ostvarili u gustinama setve sa oko 50.000 bilj.ha-1 (40.816 i 50.125 bilj.ha-1). Hibrid ZP 539 u svim ostalim gustinama (60-100.000 bilj.ha-1) imao je približne vrednosti prinosa (13,44 t ha-1- 13,93 t ha-1). Najbolje rezultate prinosa hibridi ZP 360 i ZP 580 ostvarili su u gustinama 80, 90 i 100.000 bilj.ha-1, hibrid ZP 633 u gustinama 60, 70, 80 i 90.000 bilj.ha-1, a hibridi ZP 677 i ZP 704 u gustinama 70, 80, 90 i 100.000 bilj.ha-1. Analizom zavisnosti ostvarenih prinosa hibrida kukuruza od gustine setve utvrđena je krivolinijska regresija. U navodnjavanju mogu se očekivati sledeće vrednosti maksimalnih prinosa: ZP 360 - 14,19 t ha-1 setvom u gustini 93.500 bilj.ha-1, ZP 539 - 14,03 t ha-1 u gustini 78.500 bilj.ha-1, ZP 580 - 14,41 t ha-1 u gustini 95.700 bilj.ha-1, ZP 633 -13,64 t ha-1 u gustini 80.000 bilj.ha-1, ZP 677 - 13,31 t ha-1 u gustini 92.250 bilj.ha-1 i ZP 704 - 14,33 t ha-1 u gustini 84.111 bilj.ha-1

Uticaj vodnog režima černozema i đubrenja na prinos kukuruza u uslovima direktne setve

The results obtained in the ten-year trial (2000-2009) carried out under agro-ecological conditions of Zemun Polje are presented in this study. The objective was to determine effects of soil water regime (A) and the fertilizer rates (B) on the yield of maize directly sown in chernozem. The trial was set up according to the block design under conditions of rain fed and irrigation with the three NPK levels: B1 - Ø; B2 - 150 kg nitrogen ha-1, 105 kg phosphorus ha-1 and 75 kg potassium ha-1; B3 - 300 kg nitrogen ha-1, 210 kg phosphorus ha-1 and 150 kg potassium ha-1. Maize was sown with the John Deere-7200 MaxEmerge 2 planter. Results were processed by the factorial analysis of variance and the LSD test, while the dependence of the yield on the water regime was established by the regression analysis. Obtained results showed that the formation of yield had been significantly affected by the water regime and fertilizing. The average yield amounted to 7.25 t ha-1 and 9.31 t ha-1 under rain fed and irrigation conditions, respectively. The following yields were obtained on the average over fertilizing variants: B1- 6.46 t ha-1, B2- 8.74 t ha-1 and B3- 9.64 t ha-1. The yield of 7.74 t ha-1 can be expected in the variant B1, if 450 mm of water enters the soil surface during the growing season. With 20 mm more water the yields expected in variants B2 and B3 could be 10.60 t ha-1 and 11.70 t ha-1, respectively.U radu su prikazani rezultati desetogodišnjeg ogleda (2000-2009) izvedenog u agroekološkim uslovima Zemun Polja. Cilj je bio da se utvrdi uticaj vodnog režima zemljišta (A) i nivoa đubrenja (B) na prinos kukuruza, koji je sejan na černozemu direktno u strnište. Ogled je bio postavljen po metodi blok sistema, u prirodnom i irigacionom vodnom režimu, u varijantama primene sledećih količina NPK hraniva: B1- Ø kg ha-1; B2 - 150 kg N ha-1, 105 kg P ha-1 i 75 kg K ha-1; B3- 300 kg N ha-1, 210 kg P ha-1 i 150 kg K ha-1. Setva hibrida kukuruza ZP 704 je obavljana sejalicom John Deer- 7200 MaxEmerge 2. Rezultati prinosa su obrađeni analizom varijanse i LSD testom, a regresionom analizom utvrđena je zavisnost prinosa i količine vode. Rezultati pokazuju da su vodni režim zemljišta i đubrenje veoma značajno uticali na formiranje prinosa kukuruza. U prirodnom vodnom režimu ostvaren je prosečan prinos 7,25 t ha-1, a u irigacionom 9,31 t ha-1. U proseku, po varijantama đubrenja dobijene su sledeće vrednosti: B1- 6,46 t ha-1, B2- 8,74 t ha-1, B3-9,64 t ha-1. U varijanti B1 može se očekivati maksimalni prinos 7,74 t ha-1, ako tokom vegetacionog perioda na površinu zemljišta dospe 450 mm vode. Sa 20 mm više vode u varijantama B2 i B3 mogu se očekivati prinosi 10,60 t ha-1 i 11,70 t ha-1

Uticaj gustine setve na prinos ZP hibrida kukuruza

The study presents effects of seven sowing densities (G1 - 40,816, G2 50,125, G3 - 59,523, G4 - 69,686, G5 - 79,365, G6 - 89,286 and G7 - 98,522 plants ha-1) on grain yield of six ZP maize hybrids (ZP 360, ZP 539, ZP 580 ZP 680, ZP 677, ZP 704). The trial was performed on chernozem in experimental fields of the Maize Research Institute, Zemun Polje in the period 1998-2000. A 4-replicate three-year two-factorial trial was set up according to the split-plot method under rainfed conditions. Obtained results indicate to statistically very significant differences in grain yields over investigation years and among maize hybrids. The lowest average yield (6.05 t ha-1), with statistically very significant differences in relation to other two years (1988 - 11.52 t ha-1, 1999 - 11.35 t ha-1) was achieved in the year with the smallest amount of precipitation during the growing season (2000). The highest yields were obtained at different densities in dependence on weather conditions during the growing season and maize hybrids. In relatively favorable years the highest yields of the studied hybrids were obtained in the following densities: ZP 360 - 80-90,000 plants ha-1; ZP 539 -80.000 plants ha-1; ZP 580 - 70-80,000 plants ha-1; ZP 633 - 70,000 plants ha-1; ZP 677 - 60-70,000 plants ha-1; ZP 704 70-80,000 plants ha-1. The following densities were the most favorable under conditions of pronounced water deficit during the growing period: ZP 360 - 70,000 plants ha-1; ZP 539 - 60-70,000 plants ha-1; ZP 580 - 50-60,000 plants ha-1; ZP 633 - 70,000 plants ha-1; ZP 677 - 50-60,000 plants ha-1; ZP 704 - 60-70,000 plants ha-1.U radu su prikazani rezultati proučavanja uticaja sedam gustina setve ( G1 40.816 bilj/ha, G2 -50.125 bilj/ha, G3 - 59.523 bilj/ha, G4 - 69.686 bilj/ha, G5 -79.365 bilj/ha, G6 - 89.286 bilj/ha, G7 - 98.522 bilj/ha) na prinos zrna šest ZP hibrida kukuruza (ZP 360, ZP 539, ZP 580, ZP 680, ZP 677, ZP 704). Trogodišnja ispitivanja (1998-2000) obavljena su u agroekološkim uslovima Zemun Polja u prirodnom vodnom režimu. Dobijeni rezultati pokazuju da su, u godinama proučavanja, između ispitivanih hibrida i gustina ostvarene statistički veoma značajne razlike prinosa zrna kukuruza. U godini sa najmanje padavina tokom vegetacije (2000), ostvareni su najniži prosečni prinosi (6,05 t/ha), sa statistički veoma značajnom razlikom u odnosu na druge dve godine (1988. - 11,52 t/ha, 1999. - 11,35 t/ha). U zavisnosti od meteoroloških uslova tokom vegetacije najviši prinosi ostvareni su različitim gustinama setve. U relativno povoljnijim godinama za gajenje kukuruza ispitivani hibridi ostvarili su najbolje rezultate prinosa u sledećim gustinama: ZP 360 - 80-90.000 bilj/ha, ZP 539 - 80.000 bilj/ha ZP 580 -70-80.000 bilj/ha, ZP 633 -70.000 bilj/ha, ZP 677 - 60-70.000 bilj/ha, ZP 704 - 70-80.000 bilj/ha. U uslovima izrazitog deficita vode tokom vegetacije najpovoljnije gustine su: ZP 360 -70.000 bilj/ha, ZP 539 60-70.000 bilj/ha, ZP 580 - 50-60.000 bilj/ha, ZP 633 - 70.000 bilj/ha, ZP 677 -50-60.000 bilj/ha, ZP 704 - 60-70.000 bilj/ha

Long term effects of different soil tillage systems on maize (Zea mays L.) yields

The effects of three tillage systems: no-tillage (NT), reduced tillage (RT) and conventional tillage (CT), and three levels of fertilization (0, 258 and 516 kg/ha NPK (58: 18: 24)), on the maize yield during ten years (1999-2008) were analyzed on the chernozem soil type in Zemun Polje, Serbia. Statistical analyses showed significant effects of all three factors i.e., year, soil tillage and amount of fertilizers, and their interactions on the maize yield. The ten-year averages showed that the highest yields were observed with CT (10.61 t/ha), while the averages with RT and NT were lower (8.99 t/ha and 6.85 t/ha, respectively). The results of the influence of the amount of the applied fertilizers on maize yield showed that the lowest yield was in the zero level of fertilization 7.71 t/ha, while the yield was raised when the 258 kg/ha and 516 kg/ha NPK were applied (9.18 t/ha and 9.56 t/ha, respectively). Analyzing the influence of the soil tillage systems on maize production with respect to the amounts of applied fertilizers, this research revealed the benefits of CT under the presented agroecological conditions, irrespective of the level of applied fertilizer

Sistemi obrade i prinos kukuruza na černozemu

Long-term experiments (1998-2000) with different regimes of both, tillage (direct sowing into stubble field - Al, tillage with a soil miller - A2 and conventional tillage - A3) and fertilising (without fertilising - Bl, standard rate - B2 and enhanced fertilising - B3) of soil under maize were performed with the aim to find out the possibility to exclude certain operations from soil tillage. Furthermore, effects of these regimes on maize yield, abundance and distribution of weed species were also observed. The trial was carried out on chernozem at the experimental farm of the Maize Research Institute, Zemun Polje. The hybrid ZPSC 704, locally developed, was directly sown by a planter at the rate of 60,600 plants ha-1. Obtained results point out to the advantages of conventional tillage over other regimes in respect to yield (A1 - 5.36 t x ha-1, A2 - 7.93 t x ha-1 and A3 - 9.86 t x ha-1) and abundance and distribution of weed species (A1 - 45.6 plants x m-2, A2 - 38.9 plants x m-2 and A3 - 7.0 plants x m-2). The application of higher rates of fertilisers resulted in significantly higher yield in comparison to other variants (B1 - 6.70 t x ha-1, B2 - 7.58 t x ha-1 and B3 - 8.86 t x ha-1), but the number of weed plants was also significantly higher. Moreover, gained results indicate that it is possible to recover the yield loss with higher rates of fertilisers if certain tillage operations have been omitted.Višegodišnja proučavanja (1998-2000) različitih sistema obrade (direktna setva u strnište - A1, obrada frezom - A2 i klasična obrada - A3) i đubrenja (bez đubrenja -B1, standardna doza - B2 i pojačano đubrenje - B3) zemljišta pod kukuruzom imala su za cilj iznalaženje mogućnosti izostavljanja pojedinih operacija pri obradi zemljišta, kao i njihov uticaj na prinos kukuruza, brojnost i zastupljenost dominantnih vrsta korova. Ogled je izvođen na černozemu, oglednog polja Instituta za kukuruz 'Zemun Polje'. Sejan je hibrid iz domaće selekcije ZPSC 704 sejalicom za direktnu setvu u gustini 60 600 bilj. x ha-1. Rezultati proučavanja ukazuju na prednost konvencionalne obrade u odnosu na ostale načine sa aspekta visine ostvarenih prinosa (A1 - 5,36 t x ha-1, A2 - 7,93 t x ha-1 i A3 - 9,86 t х ha-1), a takođe i sa aspekta zastupljenosti i brojnosti korovskih vrsta (A1 -45,6 jedinki х m-2, A2 - 38,9 jedinki х m-2 i A3 - 7,0 jedinki х m-2). Korišćenjem pojačane doze đubriva dobijeni su prinosi značajno viši u odnosu na ostale varijante (B1 - 6,70 t х ha-1, B2 - 7,58 t х ha-1 i B3 - 8,86 t x ha-1), ali je i brojnost korovskih jedinki, takođe, značajno veća. Osim ovoga rezultati pokazuju da je moguće povećanim dozama đubriva nadoknaditi manjak u prinosu nastao usled izostavljanja pojedinih operacija pri obradi zemljišta

Višegodišnji uticaj različitih sistema obrade zemljišta na energetsku efikasnost i prinos kukuruza

Adoption and improvement of different tillage systems toward agricultural sustainability has a great social, economical and environmental impact. The base of sustainability is a system productivity as ratio of output to input in a given system, measured in the same units, commonly as energy requirements. The objective of this study was to evaluate the aspect of energy requirements in the different soil tillage systems regarding total energy consumption under conventional tillage. The appropriate measuring at the field conditions, conducted during the period of investigation 1998-2010 on the soil type of slightly calcareous Chernozem. Maize crop was grown under typical Balkan two-crop rotation with winter wheat. Grain yield of maize and energy efficiency were fallowed on the different tillage systems: conventional tillage (CTS - summer tillage of stubble + deep autumn plowing + pre-sowing preparation); reduced tillage (RTS - heavy disc harrowing ); and no-tillage (NT - direct sowing into wheat stubble covered with all amounts of straw residues using no-till planter John Deer Max emerge 2 with the double disc openers). Results of examination have indicated high energy efficiency of No tillage Systems (NTS). Besides statistically lower yields being recorded comparing to a conventional tillage, good results with No-till system have actualizing necessity to continue research on new growing technology and to improve its implementation. .Efikasno unapređenje različitih sistema obrade zemljišta u pravcu održive poljoprivredne proizvodnje, danas ima poseban socijalni, ekonomski i ekološki značaj. Osnova održivosti proizvodnje, jeste produktivnost sistema gajenja određene kulture izražena kao odnos uložene energije u procesu proizvodnje i dobijene energije oličene u prinosu glavnog proizvoda. Cilj ovog rada bio je da upoređenjem ispitivanih sistema obrade zemljišta sa energetskog i proizvodnog aspekta odgovori na pitanje održivosti proizvodnje kukuruza. Odgovarajuća merenja u poljskim uslovima, su obavljena u višegodišnjem periodu 1998-2010. godine, na zemljištu tipa karbonatni černozem. Kukuruz je gajen u balkanskom dvopoljnom plodoredu, naizmeničnim smenjivanjem sa ozimom pšenicom. Prinos suvog zrna i energetska efikasnost praćeni su na različitim sistemima obrade zemljišta: konvencionalna obrada (CTS-letnja obrada strništa + duboko jesenje oranje + predsetvena obrada zemljišta); redukovane obrade (RTS - obrada teškom tanjiračom), i direktne setve (NTS - usejavanjem u strnište pokriveno kompletnom masom žetvenih ostataka sejalicom za direktnu setvu, John Deer Max Emerge 2). Rezultati istraživanja ukazuju na visoku energetsku efikasnost sistema direktne setve (NTS), što bez obzira na statistički niže prinose ostvarene u odnosu na klasičnu obradu zemljišta aktuelizuje potrebu nastavka razvojnih istraživanja na implementaciji novih tehnologija gajenja kukuruza.

Uticaj vremena setve na prinos ZP hibrida kukuruza

These experiments were conducted in the period 2003-2008 in Zemun Polje. Five hybrids were investigated in six sowing dates - on April 5th (Sd1), 15th (Sd2) and 25th (Sd3), and on May 5th (Sd4), 15th (Sd5) and 25th (Sd6). Three unfavorable years for the maize production were distinguished in this period: 2003 with 210.0 mm, 2007 with 290.1 mm and 2008 with 224.6 mm of precipitation; 2005 was moderately favorable, with 387.4 mm of precipitation. Two years were favorable for the maize production, both in terms of precipitation amounts and distribution: 2004 with 427.6 mm and 2006 with 417.1 mm. The highest average yield was achieved in Sd2 (11.21 t/ha - 100%). On the other April sowing dates, average yield was lower: on Sd1 - 11.04 t/ha (98.48%), on Sd3 - 10.97 (97.86%). The effects of the May sowing dates were significantly lower comparing with the Sd2: Sd4 - 10.53 t/ha (93.93%), Sd5 - 10.46 t/ha (93.31%) and Sd6 - 9.71 t/ha (86.62%). The highest yielding hybrid was ZP 684 (11.16 t/ha). These results doubtlessly point to the mid April sowing date as an optimum for maize in Serbia.Vreme setve spada u faktore koji imaju značajan uticaj na nivo prinosa kukuruza. Optimalan rok setve bi se mogao definisati kao vreme setve kojim se obezbeđuje nicanje kukuruza u najpovoljnijem trenutku kako bi se maksimalno iskoristili uslovi vegetacionog perioda i formirao što veći prinos. Ova ispitivanja obavljena su u periodu od 2003. do 2008. godine u Zemun Polju. Ispitivano je pet hibrida u šest rokova setve: tri u aprilu (5., 15. i 25.) i tri u maju (5., 15. i 25.). U toku ispitivanja, tri godine su bile nepovoljne za proizvodnju kukuruza: 2003. sa 210,0 mm padavina, 2007. sa 290,1 mm i 2008. sa 224,6 mm. Jedna godina (2005) je imala umereno povoljne uslove - 387,4 mm padavina. Dve godine su bile povoljne u smislu količine i rasporeda padavina: 2004 sa 427,6 mm i 2006. sa 417,1 mm. Najviši prinos ostvaren je pri setvi kukuruza 15. aprila (11,21 t/ha), koji je uzet kao referentna vrednost (100,00%). U ostalim rokovima setve u aprilu prinos je bio niži: Sd1 11,04 t/ha (98,48%), Sd3 10,97 t/ha (97,86%). Setvom u maju, ostvareni su statistički veoma značajno niži prinosi u odnosu na referentnu vrednost: Sd4 - 10,53 t/ha (93,93%), Sd5 - 10,46 t/ha (93,31%) i Sd6 - 9,71 t/ha (86,62%). Hibrid ZP 684 imao je najviši prosečan prinos (11,16 t/ha), dok su svi ostali prinosi bili niži: ZP 680 za 8,23%, ZP 434 za 7,71%, ZP 580 za 4,75% i ZP 578 za 3,05%. Ove činjenice nedvosmisleno ukazuju da je setva kukuruza u aprilu, a posebno polovinom ovog meseca, najpovoljniji rok setve u Srbiji