Effects of herbicides and foliar fertilizer on maize lines

Reakcija samooplodnih linija kukuruza na primenu triketona (mezotrion i topramezon) i sulfonilurea (rimsulfuron i foramsulfuron) herbicida u preporučenoj i dvostrukoj dozi sa i bez primene folijarnih đubriva je praćena u trogodišnjem poljskom ogledu na lokalitetu Zemun Polja u periodu 2010. – 2012. godina. Paralelno, reakcija najosetljivije linije je ispitivana u kontrolisanim uslovima. Nakon primene herbicida i folijarnog đubriva vizuelno je ocenjena fitotoksičnost i izvršeno je uzorkovanje materijala za ispitivanje morfoloških parametara (površine listova, visine, sveže nadzemne mase biljaka), kao i biohemijskih parametara (sadržaja rastvorljivih proteina, slobodnih tiolnih grupa, rastvorljivih fenola i fitinskog fosfora u listovima linija kukuruza) da bi na kraju vegetacione sezone bio izmeren prinos zrna. Prema dobijenim rezultatima, triketoni i sulfonilurea herbicidi su različito uticali na posmatrane parametre linija kukuruza. Triketoni su u manjem stepenu negativno uticali na smanjenje posmatranih morfoloških parametara, dok prinos zrna nije umanjen ni pri primeni preporučenih, kao ni dvostrukih doza herbicida. S druge strane, primenjene sulfoniluree su značajno uticale na smanjenje posmatranih parametara linija kukuruza. Linije su prema osetljivosti na sulfonilurea herbicide podeljene u tri grupe: na osetljive, srednje osetljive i tolerantne. Kod najosetljivijih linija ne preporučuje se primena sulfonilurea herbicida, kod srednje osetljivih mogu se bezbedno primeniti preporučene doze sulfonilurea, mada je potreban dodatan oprez, dok se kod tolerantnih linija mogu bezbedno primeniti. U cilju smanjenja herbicidnog stresa kod ispitivanih linija zajedno sa herbicidima primenjena su folijarna đubriva. Pozitivne reakcije ispitivanih linija su zabeležene u tretmanima sa aminokiselinskim đubrivom Activeg. U slučaju merenja morfoloških parametara i prinosa zrna, primenjeno đubrivo je uticalo na povećanje merenih parametara, dok su prilikom ocenjivanja vizuelnog oštećenja nije bilo uvek pravilnosti. Takođe, u kontrolisanim uslovima, najosetljivija linija je uz primenu folijarnog đubriva pokazala veću tolerantnost kada je primenjeno folijarno đubrivo u odnosu na tretman bez đubriva...Maize inbred lines reaction on herbicides triketons (mesotrione, topramezone) and sulfonylures (rimsulfuron, foramsulfuron) in recommended and double dose with and without foliar fertilizers was examinated in three year on experimental field of Maize Research Institute „Zemun Polje“ during 2010.-2012. year. Parallel with that, reaction of the most sensitive line was performed in controled conditions. After herbicides and foliar fertilizers application phytotoxicity was assessed visually and samples for testing morfological parameters (leaf area, height, plant fresh mass) and biochemical parameters (content of soluble proteins, free thiol groups, soluble phenols and phytic phosphorus in maize leaves), and grain yield at the end of vegetation season. According to results, triketons and sulfonylureas influenced differently to observed maize parameters. Triketons had lesser negative impact on morphological parameters reduction, while grain yield was not reduced in recommended or double doses of mesotrione and topramezone. On the other hand, applied sulfonylurea herbicides significantly influenced decrease in observed maize lines parameters. Lines were divided into three groups according to their sensitivity towars those herbicides: sensitive, medium sensitive and tolerant. In sensitive lines sulfonylurea herbicides application is not recommended, in medium sensitive recommended doses could be safely applied, and in tolerant lines application is allowed. In order to reduce herbicides stress in tested lines together with herbicides foliar fertilizers were applied. Positive reaction were recorded in treatments with amino acid fertilizer Activeg. In case of meashured morphological parameters and grain yield foliar fertilizer influenced the increase in meashured parameters, while only in visual assessement results were not as ecpected. In controlled conditions the most sensitive line showed higher tolerance to herbicide in treatment with foliar fertilizer. Weaker maize response to foliar fertilizer Soluveg Green may be found in subsequent application to Activeg, that is applied together with herbicides..

CONTRIBUTION OF ORGANICALLY GROWN SPELT TO THE GRAIN QUALITY

The content of nutritionally important minerals (Fe, Mg, Zn, Ca, Mn) and some antioxidants were analyzed in spelt wheat grown during four different seasons and in semiarid conditions. The spelt wheat was organically grown in the period 2012-2015, at Maize Research Institute Zemun Polje. The crop was sown on the area of 0.33 ha and after harvesting, grain yield was measured from all production area and calculated with 14% of moisture. Then, grains were milled and content of nutrients Mg, Fe, Mn, Ca and Zn, as well as inorganic phosphorus (Pi), phytic phosphorus (Pphy), phenolics, β-carotene and glutathione (GSH), were determined in grains. The variations in content of minerals and antioxidants followed variations in sum of precipitation, as well as average air temperature. The content of Mg was significantly higher in 2015, while the Ca content was lower. Concentration of Zn and Mn continuously decreased from 2012 to 2015. The highest content of almost all investigated antioxidants was observed mostly in 2013. GSH and β-carotene content variations were also affected by the meteorological conditions of the growing season

Contribution of long-term crop rotation to weed control in maize

Crop rotation is an essential part of IWM system proposed to be implemented in maize weed control. It is especially appropriate to be used in sustainable maize production in order to suppress weed abundance on ecological and low-pesticide way. In comparison to maize continuous cropping, which is not suggestible, two- and three-years crop rotation with legume crop is more efficient in weed biomass reduction, including basic herbicide application. The aim of the study was to investigate the efficacy of combined application of crop rotation and mixture of soil (PRE) herbicides on weed species distribution. A long-term field trial organized as split-plot experiment has started in 2009 with maize sown in all four fields at the Maize Research Institute, Belgrade, Serbia. The basic treatment was a rotation system: maize continuous cropping (MC), maize-winter wheat rotation (MW), maize-soybean - w. wheat (MSW) and maize - w. wheat - soybean rotation (MWS). A pre-emergence herbicide mixture of isoxaflutole and metolachlor (Merlin 750-WG+Dual Gold 960 EC) in recommended rates (105 g a.i. ha-1 + 672 g a.i. ha-1) was applied immediately after drilling with a CO2 backpack sprayer with a four nozzle boom, using extended range nozzles (XR11002-SS, Tee Jet Spraying Systems, Wheaton, IL, USA) calibrated to deliver a spray volume of 140 L ha-1 of solution at 275.8 kPa. Herbicides were not applied in the control plot. After twelve years and completion of four rotations, maize was present again in all fields in 2021. Weed infestation level was estimated six to seven weeks after the application of herbicides. Samples were drawn randomly by the one square meter and number of weed individuals (WI) and their biomass (WB) were calculated. The data were processed by ANOVA. Our results indicated that in comparison to 2009, WI were increased in 2021 in untreated control by 44.2% in MC, 23.6% in MW, 24.6% in MSW and 18.6% in MWS. On the other hand, in treated plots WI have increased only in MC, by 62.5% and lowered by 7.7% in MW, 29.4% in MSW and 60.0% in MWS. WB has been reduced in 2021 significantly on treated as well as untreated plots in all rotation systems. The highest reduction of WB was achieved in untreated control of MWS (42.6%) and treated plot in MC (45.6%). Conclusively, it was proved that even with basic herbicide treatment with soil herbicides crop rotation could be very effec tive in weed control. On the other hand, maize continuous cropping has to be avoided in order to reduce potentials for weed infestation

Weed control in sweet maize (Zea mays var. succharata) eco-farming

Sustainability in agricultural systems is largely based on increasing biodiversity and reduc ing the input of agrochemicals. Weed species occurrence and distribution in fields is driven by anthropogenic factor and cropping measures applied for high yield achievement. In sustainable cropping systems with cultivation of specific maize varieties such as sweet maize, special at tention has been usually paid to weed control because these genotypes are additionally sen sitive to herbicides. Sweet maize is mainly consumed directly by humans and its cultivation is supposed to be conducted without chemical control of weeds, giving advantage to cover crops. Cover crops influence weed infestation level through competition for space, light, water, and minerals. The aim of the investigation was to identify the most effective species or mixtures of cover crops in weed control of sweet maize in the present agro-ecological conditions. The ex periment was conducted at the Maize Research Institute Zemun Polje, Belgrade, Serbia during 2014-2016. Sweet maize was grown after different cover crops: V1-common vetch (Vicia sativa L.), V2-field pea (Pisum sativum L.), V3-winter oats (Avena sativa L.), V4-fodder kale (Brassica oleracea convar. acephala L.), V5-common vetch+oats and V6-field pea+oats, V7- straw and V8- bare soil as a control. The preceding crop was winter wheat and each treatment had three repetitions. Sowing of cover crops was done in autumn while incorporation by ploughing was performed in spring, one week before sweet maize sowing (hybrid ZP SC 421su)in a density of 65.000 plants ha-1. Six weeks after sowing, the weed association composition was analysed by weed species, number of individuals, and biomass determination per m2. After that, weeds were removed by hand hoeing and herbicides were not applied. The 19 weed species were determined during the investigation while seven species were present in each year and made a base of association: Solanum nigrum L., Sorghum halepense (Pers.) L., Chenopodium album L., C. hybridum L., Amaranthus retroflexus L., A. hybridusL. and A. albus L.. Number of weed species, weed individuals and their biomass were significantly affected by year, cover crop, and their interaction. The highest number of individuals was detected in 2016 which was favourable regarding sum and distribution of precipitation. V1, V2 and V3 were the most efficient cover crop treatments in weed control, with the lowest number of weed species and individuals. In average for three years, weed biomass was significantly reduced after cultivation of field pea, V2 (820.2 g m-2) and its mixture with oats, V6 (794.3 g m-2) in comparison to control, bare soil, V8 (1582.6 g m-2)

Uticaj sistema gajenja na zastupljenost korova i status vode u kukuruzu

Growing modern hybrids in narrow plant spacing together with nitrogen and herbicide application gives an advantage to maize crops over weeds. The aim of the present investigation was to evaluate the effect of nitrogen form, maize row spacing and herbicide treatment on weed and maize biomass and water usage, as well as maize yield. The investigation was conducted at the Maize Research Institute Zemun Polje, Belgrade during 2014-2016. A field experiment was set up as a split-split-plot block design with four replications. The maize hybrid ZP388 was planted, and a standard and a slow-release form of urea were applied. For each N source, maize was grown at two row spacings: narrow of 50 cm, and standard of 70 cm, while weed control treatments included: C - without herbicide application, T - application of a pre-emergence mix of herbicides. Sowing was done in the second decade of April, 2014, 2015 and 2016. Six weeks after herbicide application, the fresh biomass of weeds uprooted from 1 m2 and aboveground biomass of ten crop plants per plot were measured together with dry matter after drying in a laboratory oven. Water content (%) in weed and maize plants was calculated as a relation between fresh and dry biomass. Maize yield was measured at the end of each growing season and calculated with 14% of moisture. All data were processed by ANOVA. The fresh and dry biomass of weeds were significantly (P>0.05) higher in untreated control than in the treated variant, while differences in water content were not significant between the two treatments. Row spacing and urea form did not cause significant differences in weed parameters. Related to this, maize fresh and dry biomass, as well as water content, were higher in herbicide-treated variants than in control but differences were insignificant. Maize biomass was somewhat higher in 50 cm rows and after application of the slow-release urea fertilizer. Yield was higher from 70 cm rows and after application of the slow-releasing urea and the herbicides.Gajenje novostvorenih hibrida kukuruza uz smanjeno međuredno rastojanje i primenu đubriva i herbicida, daje prednost usevu u odnosu na korove. Cilj istraživanja je bio da se ispita uticaj forme azotnog đubriva, međurednog rastojanja i primene herbicida na biomasu korova i kukuruza i status vode, kao i na prinos zrna kukuruza. Istraživanje je sprovedeno u Institutu za kukuruz Zemun Polje, Beograd, tokom 2014-2016. godine. Hibrid kukuruza ZP388 je sejan uz primenu standardne i spororazgradive uree. U okviru svake forme azotnog đubriva, kukuruz je gajen u međurednom rastojanju od 70 cm i smanjenom rastojanju od 50 cm, uz primenu kombinacije herbicida posle setve a pre nicanja (T) i bez primene herbicida, kontrola (C). Setva je obavljana u drugoj dekadi aprila u 2014, 2015 i 2016. godini. Šest nedelja posle primene herbicida, merena je sveža masa korova sa površine od 1 m2 i nadzemna masa 10 biljaka kukuruza po svakoj varijanti, zatim su biljke korova i useva sušene u laboratorijskoj sušnici, nakon čega je izmerena njihova suva masa. Sadržaj vode (%) u biljkama korova i kukuruza je određen iz odnosa sveže i suve mase. Prinos kukuruza je meren na kraju vegetacionog perioda i obračunat sa 14% vlage u zrnu. Svi dobijeni podaci su statistički obrađeni analizom varijanse (ANOVA). Sveža i suva masa korova su bile značajno (P>0.05) veće u kontrolnoj nego u herbicidima tretiranoj varijanti, dok se sadržaj vode u biljkama nije značajno razlikovao između ova dva tretmana. Međuredno rastojanje i forma azotnog đubriva nisu uticali na pojavu značajnih razlika u merenim parametrima korova. U vezi sa navedenim, sveža i suva masa kukuruza kao i sadržaj vode u biljkama, su bili veći na tretiranoj u odnosu na kontrolnu površinu ali razlike nisu bila satistički značajne. Sveža masa kukuruza je u izvesnom stepenu bila veća pri međurednom rastojanju od 50 cm i nakon primene spororazgradive uree, dok je prinos zrna kukuruza bio veći na međurednom rastojanju od 70 cm i nakon primene spororazgradive uree i herbicida

Energy distribution between maize and weeds

The aim of the study was to investigate the variations in accumulation of dry substance and water in maize and weeds, induced by two herbicide types (applied pre- and post-emergence). Weeds tend to captivate higher energy amounts than crop plants. Greater free energy of water indicated increased energy consumption for non-spontaneous processes in weeds. Relatively unchanged net heat of combustion of maize and lower net heat of combustion of weeds indicated herbicide ability to reduce energy accumulation by weeds and to remain it constant in maize plants

Sadržaj nekih antioksidanata u zrnu kukuruza i soje iz združenog useva

Intercropping, as a combination of different crops at the same time and the same field, enables interaction of their roots, improving plant growth and stress tolerance, thus improving nutritional quality of produced grains. The investigation was aimed to examine the effect of different cropping systems: intercropping in combination with alternating rows and alternating strips of maize and soybean, as well as single cropping, combined with different fertilization regimes (conventional, application of organic fertilizer, bio-fertilizer and control) on the antioxidant content (glutathione [GSH], phenolics and yellow pigment [YP]) in red maize and black soybean grain. Black soybean is richer in antioxidants than red maize. Season expressed the highest influence on the level of GSH, phenolics and YP in maize and soybean, while cropping system and fertilization regime influenced GSH and phenolics. The antioxidant level in grains with greater weight corresponded with an increased GSH level for maize, as well as an increased GSH and phenolic level for soybean, while smaller grains were characterised by the increased YP content. Generally, antioxidant content was increased mainly by alternating strips in maize grain and by alternating rows in soybean grain. Bio-fertilizer had the highest impact on an increase in GSH in maize grain and YP in soybean grain, while organic fertilizer was important for acquiring of GSH and phenolics in soybean grain.Združeni usev, kao kombinacija različitih useva, koji se gaje u isto vreme i na istom polju, omogućava interakciju njihovih korenova, poboljšava rast i tolerantnost na stres, poboljšavajući tako nutritivni kvalitet proizvedenog zrna. Cilj istraživanja je bio da se ispita efekat različitih sistema gajenja: združeni usev kombinujući naizmenične redove i naizmenične trake kukuruza i soje, kao i pojedinačne useve, zajedno sa različitim režimima đubrenja (konvencionalni, upotreba organskog đubriva, bio-đubriva i kontrola) na sadržaj antioksidanta (glutationa [GSH], fenola i žutog pigmenta [YP]) u zrnu crvenog kukuruza i crne soje. Zrno crne soje je bogatije antioksidantima od crvenog kukuruza. Sezona je pokazala najveći uticaj na sadržaj GSH, fenola i YP kod kukuruza i soje, dok su sistem gajenja i đubrenje uticali na promene u sadržaju GSH i fenola. Sadržaj antioksidanata u zrnima sa većom masom je odgovarao povećanom nivou GSH kod kukurza, kao i povećanju nivoa GSH i fenola kod soje, dok su zrna manje mase imala već i sadržaj YP. Uopšteno, sadržaj antioksidanata je uglavnom bio povećan u zrnu kukuruza pri gajenju u naizmeničnim trakama, a u zrnu soje pri gajenju u naizmeničnim redovima. Bio-đubrivo je pokazalo najveći uticaj na povećanje sadržaja GSH u zrnu kukuruza i YP u zrnu soje, dok je organsko đubrivo ispoljilo uticaj na nakupljanje GSH i fenola u zrnu soje

The Response of Maize Lines to Foliar Fertilizing

The objective of this study was to evaluate the impact of two foliar fertilizers applied on five maize (Zea maysL.) lines. Fertilizers were applied at different growth stages of maize, during three consecutive years (2010-2012) at the experimental field of the Maize Research Institute "Zemun Polje", Serbia. Maize growth parameters such as fresh matter, height, leaf area and grain yield were recorded. Foliar fertilizer with amino acids (FAA) was more advantageous to maize plants compared to fertilizer containing phosphorus (FP) as a main component. Applied FAA has shown positive effects by increasing fresh matter, leaf area index, and plant height in all three years. In 2012, due to unfavorable meteorological conditions, grain yield and harvest index were very low, compared to the previous two years, although, positive effects on morphological traits were observed 21 days after treatments (DAT), as well as in the anthesis stage. The best results of 30% of grain yield and harvest index increase were recorded in line L1 in 2010 and 2011. The same line had an increase of more than 40% of fresh matter and leaf area on average for all three years. The positive effects that have been noticed in this research could recommend foliar fertilizing with fertilizer containing N in a form of an amino acids complex

Does continuous cropping of maize contribute to infestation with Johnsongrass (Sorghum halepense (L.) Pers.)?

Johnsongrass (Sorghum halepense (L.) Pers.) is a very common weed in maize fields in Serbia. Dense Johnsongrass infestations severely limit maize production, especially under continuous maize cropping. The key tool to manage this weed is to implement multiple control strategies when Johnsongrass is first observed and not to wait until it is firmly established. Experiments were conducted in the Maize Research Institute (MRI), Zemun Polje, Belgrade, in order to examine how economically driven continuous cropping of maize influences weed infestation, especially the distribution and abundance of Jonhsongrass, as well as maize productivity. The maize hybrid ZP 606 was grown in continuous cropping from 2009 to 2018 at a density of 59,500 plants ha-1. The experimental field was split into a part treated with the pre-emergence herbicide isoxaflutole + metolachlor (750 + 960 g a.i.) and untreated control. The level of complete weed infestation was evaluated 4-5 weeks after herbicide application by determining the number of weed individuals per species (NI), total fresh biomass (TB) and total dry weight (TDW) of all weeds and Johnsongrass fresh biomass (JB) and dry weight (JDW). Maize harvest index (HI) and grain yield (GY) were determined at the end of each growing period. All measured weed parameters were highly dependent on agro-meteorological conditions of the year, herbicide application and their interaction. On average, TDW was 760.7 g m-2 in the control plot, and 142.2 g m-2 in the treated plot, while Johnsongrass participated with 34.8% and 48.7%, respectively. Herbicide application reduced JDW by 77.6% on average, even though its biomass increased over the years. A regression analysis revealed that GY was negatively influenced by JDW (R2= - 0.094) in untreated control, while GY was higher with a lower JDW under herbicide treatment (R2=-0.4439). Continuous cropping of maize should be replaced with crop rotation in order to prevent Johnsongrass prevalence and to obtain higher crop productivity.Divlji siriak (Sorghum halepense (L.) Pers.) je vrlo čest korov na poljima u Srbiji. Intenzivna zakorovljenost divljim sirkom ozbiljno ograničava proizvodnju kukuruza, naročito kada se on gaji u monokulturi. Suština borbe protiv ovog korova je pravovremena primena više mera suzbijanja čim se divlji sirak uoči i pre nego što razvije veliku masu rizoma i dobro se ukoreni. Poljski ogled je izveden u Institutu za kukuruz Zemun Polje, sa ciljem da se utvrdi kako profitom dirigovano gajenje kukuruza u monokulturi utiče na zakorovljenost, naročito na rasprostranjenost i brojnost divljeg sirka, kao i na produktivnost kukuruza. Hibrid ZP 606 je gajen u monokulturi u periodu 2009-2018. godine u gustini od 59.500 biljaka ha-1. Polje pod kukuruzom u monokulturi je podeljeno na deo na kome je primenjivan herbicid pre nicanja useva (isoksaflutol + metolahlor (750 + 960 g am) i deo koji nije bio tretiran - kontrola. Intenzitet zakorovljenosti je određen 4-5 nedelja nakon primene herbicida merenjem broja jedinki vrsta (NI), ukupne sveže biomase (TB) i ukupne suve mase (TDW) svih korova i sveže biomase divljeg sirka (SB) i njegove suve mase (JDW). Žetveni indeks (HI) i prinos zrna (GY) određeni su na kraju vegetacionog perioda kukuruza. Svi parametri korova u velikoj meri su zavisili od agro-meteorološkoh uslova godine, primene herbicida i njihove interakcije. U proseku, TDW je iznosila 760,7 g m-2 u kontroli i 142,2 g m-2 na tretiranoj parceli, od čega je udeo suve mase divljeg sirka bio 34,8% u kontroli i 48.7% na tretiranoj parceli. Primena herbicida smanjila je suvu masu divljeg sirka prosečno za 77.6%, iako se ona sa godinima povećavala. Prema regresionoj analizi, JDW je negativno uticala na GY (R2= - 0,094) u kontroli, dok se GY povećavao sa smanjenjem JDW u varijanti sa primenjenim herbicidom (R2=-0,4439). Monokulturu kukuruza bi trebalo zameniti plodoredom da bi se sprečilo zakorovljavanje divljim sirkom i postigla veća produktivnost useva

The impact of crop density on grain filling and water retention in maize grains

Sowing density affects not only crop growth, but also grain filling, including grain dry-down. Maize hybrids with upper-standing leaves allow to be grown in higher densities, what could affect some traits during ripening. An experiment with six maize hybrids (ZP388, ZP5550, ZP5601, ZP6263, ZP6364, ZP707), grown at 59,523 (D1) and 89,286 plants ha-1 (D2), during 2019 and 2020 was established. Maize cobs were sampled 15 days after pollination (DAP), according to 10 day time-schedule (five times), up to the harvesting. Fresh weight of grains, water percentage, as well as grain yield and shelling percentage at the end of vegetative cycle were determined. Gradual and significant increase in grain fresh weight was noticed at D1, while at D2 greater values were obtained between 15th and 25th day, as well as between 45th and 55th DAP. At D1, continual increase in grain weight was observable for all hybrids, except for ZP6364, where drop 45th55th day was observable. For ZP388, significantly higher values were noticeable at D1, at 55th DAP (31.83 g) and also at D2, 15th45th DAP (from 24.06 to 32.02 g), including steeper drop to the 55th day (24.39 g), in regard to other hybrids. Significant and continual decrease in water content were noticed in grains of all of examined hybrids at D2, while at D1trend was slowed 45th55th DAP, having the lowest values for ZP5550, ZP5601, and ZP6263. Significantly higher average grain yield achieved ZP6364 (10.05 and 11.35 t ha-1 , at D1 and D2, respectively), and D2, compared to D1 (>830 kg ha-1 ). Similar trend was observable for shelling percentage with 0.71% greater value obtained at D2. ZP707 had the highest value, 82.80% and 90.11% for D1 and D2, respectively. It could be concluded that, up to the 55th DAP, maize grain gained greater weight and retained higher water amounts at D1, while grain dry-down started from the 45th day and was greater at D2. This was followed with greater grain yield and shelling percentage. From this standpoint, ZP6263 expressed the best features, according to yield potential and grain dry-down