Management of soil organic carbon in maintaining soil productivity and yield stability of winter wheat

The objective of this study was to estimate how soil organic carbon influences winter wheat yield in the South Pannonian Basin. The treatments evaluated were: fertilized 3 year and 2 year crop rotation, fertilized wheat monoculture and unfertilized 3 year and 2 year crop rotation in the 38 years of continuous cropping (1970-2007). These treatments showed a declining trend of soil organic carbon in the 0-30 cm soil layer, respectively. On average, the plow-layer of the treatments lost 10% of soil organic carbon found at the beginning of the investigated period. The plow-layer of the unfertilized treatments reached a possible soil organic carbon threshold (1.16%) after balance on decomposition and formation was observed. We found that soil organic carbon preservation coupled with proper management such as crop rotation and fertilization is important for preserving soil productivity, and when soil organic carbon increases it could benefit winter wheat yield. Obtained results are valuable for developing a sustainable cropping technology for winter wheat and soil conservation

TOTAL AND HOT-WATER EXTRACTABLE CARBON RELATIONSHIP IN CHERNOZEM SOIL UNDER DIFFERENT CROPPING SYSTEMS AND LAND USE

A study was conducted to determine the hot water extractable organic carbon (HWOC) in 9 arable and 3 non arable soil samples on Haplic Chernozem. The hot water extractable carbon represents assimilative component of the total organic matter (OM) that could contain readily available nutrients for plant growth. The obtained fraction of organic carbon (C) makes up only a small percentage of the soil OM and directly reflects the changes in the rhizosphere. This labile fraction of the organic matter was separated by hot water extraction at 80°C. In our study the HWOC content in different samples ranged from 125 mg g-1 to 226 mg g-1. On the plots that are under native vegetation, higher values were determined (316 mg g-1 to 388 mg g-1). Whereas samples from arable soils were lower in HWOC. It was found that this extraction method can be successfully used to explain the dynamics of the soil OM. Soil samples with lower content of the total OM had lower HWOC content, indicating that the preservation of the OM depends on the renewal of its labile fractions

TOTAL AND HOT-WATER EXTRACTABLE CARBON RELATIONSHIP IN CHERNOZEM SOIL UNDER DIFFERENT CROPPING SYSTEMS AND LAND USE

A study was conducted to determine the hot water extractable organic carbon (HWOC) in 9 arable and 3 non arable soil samples on Haplic Chernozem. The hot water extractable carbon represents assimilative component of the total organic matter (OM) that could contain readily available nutrients for plant growth. The obtained fraction of organic carbon (C) makes up only a small percentage of the soil OM and directly reflects the changes in the rhizosphere. This labile fraction of the organic matter was separated by hot water extraction at 80°C. In our study the HWOC content in different samples ranged from 125 mg g-1 to 226 mg g-1. On the plots that are under native vegetation, higher values were determined (316 mg g-1 to 388 mg g-1). Whereas samples from arable soils were lower in HWOC. It was found that this extraction method can be successfully used to explain the dynamics of the soil OM. Soil samples with lower content of the total OM had lower HWOC content, indicating that the preservation of the OM depends on the renewal of its labile fractions

Maize (Zea mays L.) yield stability dependence on crop rotation, fertilization and climatic conditions in a long-term experiment on Haplic Chernozem

Temperate regions are known to differ in climatic conditions which can considerably affect maize vegetative growth and yield. In order to determine the year-by-treatment interaction stability analysis was performed, while relative stability was determined by comparing selected treatments versus yield difference of selected cropping systems on Haplic Chernozem (CHha). Analysis of variance for maize grain indicated differences between treatments, while significantly higher yield was observed at a fertilized 3-year (6854 kg ha(-1)) and 2-year rotation (6721 kg ha(-1)). Stability analysis (P lt 0.01) showed significant response of maize yield to the agroecological mean yield when linear regression was applied. The effect of crop rotation on maize yield was inversely proportional to the ratio of the maize in the sequence. Relative stability showed that the higher yield sensitivity to favourable climatic conditions would be with maize monoculture (r = 0.76), and unfertilized rotations showed a decreasing yield trend when mean agroecological yield was increasing (P lt 0.05). When comparing simulated root mean square error (RMSE) of yield stability, the fertilized 2-year rotation and the monoculture fit into RMSE95% confidence interval (P lt 0.05). The results demonstrated that the stability analysis can help in selection of maize technology and interpretation of environment x treatment interaction observed in a long-term experiment

Weed infestation and biodiversity of winter wheat under the effect of long-term crop rotation

The paper presents the study of the floristic composition of weeds and weed infestation in winter wheat in long-term crop rotations at the experimental station near Novi Sad (Serbia). During the study period, a total of 48 weed species were determined, out of which 33 were determined in each study year. In two study years, there were 18 common species, while 15 species determined in 1991 were not found 19 years later. On the other hand, the study in 2010 recorded 15 new species that had not been previously found. The greatest floristic diversity (20 species) was found on fertilized four-year rotation in 1991 and unfertilized two-year rotation in 2010. The lowest diversity was recorded in 2010 on fertilized four-year rotation (9 species) and fertilized three-year rotation (10 species). The highest weed infestation was recorded in 1991 on unfertilized two-year rotation (2963 plants m(-2)) and unfertilized three-year rotation (2126 plants m(-2)), which is statistically significant compared to other variants. The lowest average weed infestation was observed in 2010 on fertilized three-year rotation (40 plants m(-2)) and fertilized four-year rotation (53 plants m(-2)). Long-term crop rotations have a significant effect on the floristic composition and structure of weeds in winter wheat

Diversity of weed flora in wheat depending on crop rotation and fertilisation

The paper analyses weed flora in wheat depending on crop rotation and fertilisation in a twenty-year period. In both studied periods (1990 and 2010) the total of 49 weed species were determined on different variants of crop rotation, while 20 weed species were found in both studies. In the first research period, in 1990, there were 16 differential species, which were not found in 2010, while in the second research, after 20 years,. there were 13 new weed species, which had not been previously determined. In the second research period, the floristic diversity was significantly reduced, and in certain variants of Crop rotation (three-year rotation, unfertilised three-year rotation and twelve-year rotation) the number of species was reduced two times. In both studied periods, the dominant species were weed-ruderal plants, with the significant share of segetal plants, while the most common life forms were therophytes from the T-4 group. Apart from the positive effects of crop rotation and fertilisation on reducing weediness, the paper also focuses on the presence of species important for biodiversity conservation, such as Fumaria officinalis L. from the category of endangered species, as well as seven other species from the category of vulnerable species - Centaurea cyanus L., Consolida regalis S.F.Gray, Papaver rhoeas L., Viola arvensis Mum, Lathyrus tuberosus L., Ranunculus arvensis L. and Lamium amplexicaule L., which are most likely to survive among crops

The possibility of maize gluten application for weed control in maize and soybean

The objective of this study was to determine the effects of maize gluten on the weeds number and dry biomass in the maize and soybean experiment. Pre-emergence maize gluten application resulted with an effective weed control in maize, whereas the soybean had the significant loss of plants, due to the gluten fitotoxicity. Post-emergence application was found to be less successful compared with pre-emergence application particularly for soybean. Panicum cruss-galli L. was the most frequent weed in the both experiment. Maize gluten rate of 300 g m2 could be recommended in control of the broad leaf weeds in maize cropping as an alternative herbicide thus a substitute for mineral nitrogen. Our research can contribute to the improvement of the weed control in sustainable cropping systems

Утицај монокултуре на принос зрна соје

Проучавање проблема плодореда у производњи њивских биљака је јако заступљено. Међутим, овај проблем код соје је мање проучаван, како код нас, тако и у свету. У новије време, уобичајени и врло често присутни двопољни плодоред код пољопривредних произвођача у Србији, замењени су тропољним плодоредом са учешћем соје. За разлику од осталих њивских биљака, соја није толико осетљива на гајење у монокултури, посебно краћој. Краткотрајна монокултура (поновљена сетва) соје више утиче на ширење биљних болести и штеточина, док је опадање приноса мање изражено. Циљ овог рада је да на основу резултата истраживања спроведених путем пољског огледа на експерименталној станици Пољопривредног факултета у Земуну ″Радмиловац″ укаже на недостатке гајења соје у дуготрајној монокултури у погледу утицаја на приноса зрна

Procena indeksa efikasnosti sistema gajenja kukuruza (Zea mays L.) u višegodišnjem eksperimentu

A simple performance-based index was used to test performance among maize cropping systems referring to the food and raw material production, nutrient cycling and greenhouse gases regulation. Those indices are tools for aggregating and simplifying agroecosystem impact on the environment. The data were acquired from a long-term experiment at the Rimski Šančevi experimental station of the Institute of Field and Vegetable Crops, Novi Sad, Serbia. Observed indicators were compared by using datasets from 2001 to 2010, across five maize cropping systems. Maize continuous cropping resulted with decrease in the utilization of the agroecological potential compared with the fertilized crop rotation. Long term maize-based cropping resulted with differences in soil organic carbon content, soil pH and temporal soil NO3. However, recommended fertilizers application and crop rotation contributed to the overall agroecosystems ability to decrease the anthropogenic pressure. Accordingly, it was found that yield decrease resulted mostly from inability of the cropping systems to utilize agricultural management (tillage, fertilization, etc.) in variable environmental conditions. For the investigated trial the performance based index showed that a 2-year maize cropping had the highest capacity for sustainable maize growing.U radu je prikazana analiza indeksa performansi agroekosistema koja može da posluži kao osnova za unapređenje gajenja kukuruza. Indeksi performansi sistema gajenja kukuruza su korišćeni u cilju razdvajanja njihove efikasnosti u ostvarivanju visine prinosa, količine biljnih ostataka, kruženja hraniva i regulaciji gasova staklene bašte. Korišćeni indikatori su indirektni pokazatelji koji služe za sumiranje i pojednostavljenje tumačenja kompleksnog uticaja agroekosistema na životnu sredinu. Za obračun su korišćeni podaci sa višegodišnjeg ogleda 'Plodoredi' Instituta za ratarstvo i povrtarstvo iz Novog Sada, a praćeno je pet različitih sistema gajenja kukuruza. Istraživani sistemi ratarenja, posmatrano u dužem vremenskom periodu, značajno su uticali na svojstva zemljišta, što je dovelo do razlika u sadržaju organske materije, pH vrednosti i zemljišnog NO3. Međutim, pravilno postavljena tehnologija gajenja kod đubrenih polikultura kukuruza je uspešno kompenzovala antropogeni uticaj. U skladu sa tim, istraživanja su pokazala da opadanje prinosa dolazi kao rezultat smanjene efikasnosti pojedinih sistema gajenja kukuruza da iskoriste efekte primenjene agrotehnike (đubrenje, obradu) pri varijabilnim klimatskim uslovima. Utvrđeno je da dvopolje kukuruza ima najveći indeks efikasnosti i sposobnost da raspolaže resursima agroekosistema, dok neđubrene parcele dugoročno nemaju mogućnost očuvanja agroekosistema

Karakteristike i klasifikacija glejnih zemljišta Banat

In this paper we investigated basic characteristics of gleyic soils of Banat and presented different interpretations and classification of these soils. Twelve profiles were analyzed to access their physical and chemical properties. Investigated humogley profiles were predominantly clayic with vertic properties and under different influence of groundwater. Most of these soils we classified in Vertisols, but some of them we considered as Gleysols or Chernozems RSG (reference soil group). Eugley was under stronger influence by groundwater than humogley and showed textural uniformity, less clay content and notably higher average content of CaCO3. Eugley profiles we classified in Gleysols RSG. Every new analyzed soil profile has to be considered in particular regarding its diagnostic horizons, properties and materials and cannot be transferred from actual national classification to RSG by default.U ovom radu su ispitivane osnovne karakteristike glejnih zemljišta Banata i predstavljena različita tumačenja i klasifikacije ovih zemljišta. Analizirana su fizička i hemijska svojstva dvanaest profila zemljišta. Ispitivani humogleji su uglavnom bili glinoviti i ispoljavali vertičnost, dok je uticaj podzemnih voda na svaki profil bio različit. Većinu ovih zemljišta smo svrstali u vertisole, ali neke od njih možemo klasifikovati u referentne grupe zemljišta (RSG) glejsoli ili černozemi. Euglej je bio pod jačim uticajem podzemnih voda od humogleja i pokazivao je veću teksturnu uniformnost, manji sadržaj gline i veći prosečan sadržaj CaCO3. Ispitivani euglej smo svrstali ureferentnu grupu zemljišta glejsoli. Svaki novi profil zemljišta koji se bude analizirao trebalo bi da se posmatra posebno u pogledu njegovih dijagnostičkih horizonata, svojstva i materijala. Nijedan tip zemljišta ne sme biti prebačen u referentnu grupu po podrazumevanom nazivu