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1.
Aluminum (Al) negatively interferes with the uptake or transport of different nutrients. The aim of our work was to compare the Al tolerance and micronutrient accumulation: iron (Fe), zinc (Zn) and manganese (Mn), in cereal species (winter wheat, spring wheat, winter rye, oats and barley) contrasting in Fe efficiency. Our previous screening in a calcareous soil showed that oats and barley were more Fe-efficient than spring wheat, winter wheat or winter rye. In Al stress conditions, both oats and barley exhibited more effectiveness in Fe acquisition and translocation from root to shoot in comparison to winter wheat, spring wheat and winter rye. Also, oats and barley responded to Al toxicity by less Al-retarded shoot biomass than other cereal species. A combination of tolerance mechanisms appears to have great importance for Al tolerance including mechanisms underlying Fe efficiency in cereal seedlings.  相似文献   

2.
Economic conditions are forcing farmers to grow crops with high revenue leading to cereal-dominated crop rotations with increasing risk due to unfavourable preceding crops or preceding crop combinations. Based on a long-term field trial (1988–2001) with 15 different rotations including winter oilseed rape (OSR), winter wheat, winter barley, spring peas and spring oats, the effects of different preceding crops, pre-preceding crops and crop rotations on the grain yield of mainly OSR, winter wheat and winter barley were quantified. In the subsequent 2 years (2001/2002 and 2002/2003), winter wheat was grown on all plots in order to test the residual effects of the former crops (as preceding crops in 2002 and as pre-preceding crops in 2003) and crop rotations on growth, grain yield and yield components.

Unfavourable preceding crops significantly decreased yield of OSR, wheat and barley by 10% on average, however, with a large year-to-year variation. In addition, break-crop benefits in both crops, wheat and OSR, persisted to the second year. Wheat as preceding crop mainly decreased the thousand grain weight, and to a lesser extent, the ear density of the subsequent wheat crop. The amount of wheat yield decrease negatively correlated with the simple water balance (rainfall minus evapotranspiration) in May–July. In 2001/2002 and 2002/2003, the preceding crop superimposed the crop rotation effects, thus resulting in similar effects as observed in 1988–2001.

Our results clearly reveal the importance of a favourable preceding crop for the yield performance of a crop, especially wheat and OSR.  相似文献   

3.
Abstract. Four management systems combining high and low livestock densities (0.7 and 1.4 livestock units ha−1) and different types of organic manure (slurry and straw based FYM) were applied to an organic dairy crop rotation (undersown barley – grass–clover – grass–clover – barley/pea – oats – fodder beet) between 1998 and 2001. The effects of the management systems on crop yields and nitrate leaching were measured. In all four years, nitrate leaching, as determined using ceramic suction cups, was higher in the three crops following ploughing of grass–clover than under the barley or grass–clover. Overall, no significant differences in nitrate leaching were observed between the management systems. However, the replacement of the winter wheat crop used in the earlier experimental period (1994–97) by spring oats with catch crops in both the preceding and succeeding winters reduced nitrate leaching compared with the earlier rotation. Increasing the livestock density, which increased manure application by c. 60 kg total N ha−1, increased crop yields by 7 and 9% on average for FYM and slurry, respectively. Yields were 3–5% lower where FYM was used instead of slurry. The experiment confirmed the overriding importance of grassland N management, particularly the cultivation of the ley, in organic dairy crop rotations.  相似文献   

4.
Regional estimates of changes in soil organic carbon (SOC) pools during the historical period were obtained according to a unified approach for Kostroma (southern taiga) and Kursk (forest-steppe) oblasts. The potential pools of soil carbon were calculated with due account for the classification position of particular soils, their texture, and the character of natural vegetation. In the estimates of actual SOC pools, land use patterns and the age structure of forest stands were taken into account. It was shown that modern pools of organic carbon in the soils of Kostroma oblast are only 1–2% smaller than the potential pools; for the soils of Kursk oblast, this difference reaches 23–27%. Mean weighted values of the actual SOC contents in these oblasts decreased by 0.1–0.2 and 6.5–7.6 kg C/m2 in comparison with the potential SOC contents, respectively, which is related to their environmental specificity and to different types of land use at present and in the historical past.  相似文献   

5.
Manganese content of cereals, maize and beet as indicator of soil acidity Soil and plant samples with and without growth depressions were taken from 479 agricultural fields (sand - loam) in the former GDR and analysed for pH and Mn and Mg respectively. Depressions in growth accompanied with symptoms of Mn excess and sometimes also of Mg deficiency were observed for barley, wheat, oats, maize and beets at soil pH < 4, 7, for rye at pH < 4, 1 - 4, 4. Soil pH correlated highly negatively with the Mn concentration of plants in early growth stages. Thus toxicity levels of Mn concentration in young plants could be derived. Mn concentrations > 140 mg/kg dry matter in spring barley, > 150 mg/kg in winter barley, > 160 mg/kg in wheat, > 200 mg/kg in rye, > 300 mg/kg in oats, > 350 mg/kg in maize and > 800 mg/kg in beet indicate growth depressions because of soil acidity. In the case of simultaneous Mg deficiency these Mn values are lower for oats and rye.  相似文献   

6.
Crop response to fertilization and liming was investigated in field and pot trials on sandy loam Dystric Albeluvisols (pH 4.2–4.3). Treatments in the field trial were: 1, no fertilizer; 2, PK; 3, NK; 4, NP; 5, NPK; 6, lime; 7, lime+PK; 8, lime+NK; 9, lime+NP; 10, lime+NPK. In the pot trial, they were: 1, no fertilizer; 2, N; 3, P; 4, K; 5, NP; 6, NK; 7, PK; and 8, NPK applied to unlimed and limed soils. All treatments were in four replicates. Crops sensitive to soil acidity (winter wheat, fodder beet, spring barley and clover-timothy ley) and the less acid-sensitive winter rye, potatoes, oats and lupins and oats mixture were sown in the field trial. In the pot trial, the acid-sensitive spring barley and red clover, and the less acid-sensitive oats and lupin-oats served as the test crops. Combined application of fertilizers (NPK) increased yields of crops sensitive to soil acidity in plots receiving lime by 23%, and those of crops less sensitive to soil acidity by 18% in comparison to crops grown on unlimed soils. The results of pot experiments corroborated the field results. When N was applied alone, crop yields were always higher than those recorded for P or K treatments on both the unlimed and limed treatments. N application proved to be a prerequisite for high crop yields in the soils investigated. Thus, the efficiency of P and K fertilizers increased in the order NK<NP<NPK, with the effects being accentuated more in the limed than in the unlimed treatments. The results demonstrated the importance of multi-nutrient (NPK) fertilization in combination with liming for enhancement of high crop productivity in the unlimed soil investigated. N applied alone in combination with liming produced relatively good yields; hence, where resources are limited for the purchase of P and K fertilizers, applying N and lime can be a viable option in the short term.  相似文献   

7.
The Fusarium mycotoxins deoxynivalenol (DON) and 3-acetyl-deoxynivalenol (3-acDON) were determined in grain samples from naturally infected and Fusarium culmorum inoculated plants in field experiments in Norway during 1992–1996. The mean DON content in trials with inoculated plants was 11.8 μg/g in spring oats, 11.3μg/g in winter wheat, 28.9 μg/g in spring wheat and 31.4 μg/g in spring barley. In the natural infection trials the mean DON content was 0.32 μg/g in spring oats, 0.22μg/g in winter wheat, 1.48μg/g in spring wheat and 0.54 μg/g in spring barley. Only small differences in DON content were observed among cultivars, and significant differences were found only in winter wheat in the inoculation trials, and in spring wheat in the natural infection trials. A significant correlation was observed between the 3-acDON and DON contents in the inoculated trials in all grain species, the mean ratio of 3-acDON to DON ranging from 0.011 in wheat to 0.071 in oats.  相似文献   

8.
The relationship between seasonal agricultural drought and detrended yields (within a period from 1961 to 2000) of selected crops was assessed in the conditions of the Czech Republic, which are to some extent representative of a wider area of Central Europe. Impact of water stress was analyzed using time series of yields for 8 crops (spring barley, winter wheat, grain maize, potato, winter rape, oats, winter rye and hay from permanent meadows) for 77 districts in the Czech Republic (average district area is 1025 km2). Relative version of Palmer’s Z-index (rZ-index or rZ-i) was used as a tool for quantification of agricultural drought. The monthly values of the rZ-index for each individual district were calculated as the spatial average (only for the grids of arable land). The study showed that severe droughts (e.g., in 1981 and 2000) are linked with significant reduction in yields of the main cereals and majority of other crops through the most drought prone regions. We found a statistically significant correlation (p  0.05) between the sum of the rZ-index for the main growing period of each crop and the yield departures of spring barley within 81% (winter wheat in 57%, maize in 48%, potato in 89%, oats in 79%, winter rye in 52%, rape in 39%, hay in 79%) of the analyzed districts. This study also defined the crop-specific thresholds under which a soil moisture deficit (expressed in terms of rZ-index) leads to severe impact at the district level. This can be expressed as the sum of the monthly rZ-index during the period of high crop sensitivity to drought; for spring barley it is ?5, winter wheat ?5, maize ?9, rape ?12, winter rye ?10, oat ?4, potato ?6 and for hay ?3. The length of the sensitive period is also crop-specific and includes the months that are important for the yield formation. The results show that yields of spring barley (and spring crops in general) are significantly more affected by seasonal water stress than yields of winter crops and hay from permanent meadows. The study proved that a severe drought spell during the sensitive period of vegetative season does have a quantifiable negative effect, even within more humid regions. These results demonstrate that, at least in some areas of the CR (and probably most of Central Europe), drought is one of the key causes of interannual yield variability.  相似文献   

9.
Long-term series of observations over the spring water balance elements on fields with hydrologically contrasting agricultural backgrounds―a loose soil after fall moldboard plowing and a plowland compacted by 12–16% compared to the former soil (perennial grasses, winter crops, stubble)―have been analyzed. The values of surface runoff and water infiltration into the soil in the steppe and forest-steppe zones of European Russia have been calculated for the spring (flooding) period and the entire cold season. The hydrological role of fall plowing has been shown, and water balance elements for the current (1981–2016) and preceding (1957–1980) periods have been compared. A significant decrease in runoff and an increase of water reserve in the soil have been revealed on all plowland types. Consequences of changes in the spring water balance on plowland have been analyzed.  相似文献   

10.
In the period from September to May, the decomposition of stubble by microorganisms was more active than that during the summer period. The mineralization of stubble of sweet clover, peas, and corn was more active than that of spring wheat, barley, oats, and winter rye. The root residues of the majority of the crops were decomposed slower than the stubble. The yield of the wheat depended on the amount of afterharvest residues, their chemical composition, and the rate of their mineralization. The increase in wheat yields as dependent on the input of the stubble remains of the precursors into the soil can be arranged in the following order: wheat, corn < rye, annual herbs < peas.  相似文献   

11.
The Kemink exact soil management system is a non-inversion soil management system based on subsoiling, ridges and controlled traffic. Previous studies have documented benefits of the Kemink system used in its entirety, but the isolated effect of Kemink subsoiling has not been investigated before. To determine the isolated effect of Kemink subsoiling before and after planting two field experiments in sugar beet and barley were conducted in 1999 and 2000 under low nutrient input conditions in a conventional soil management system without recognized compaction problems. Kemink subsoiling after planting generally showed a negative effect on the growth and yield of both crops, whereas subsoiling before planting increased sugar beet yield from 8.4 to 9.5 t ha−1 and sugar beet nitrogen uptake from 48.5 to 57.4 kg ha−1. There was no effect of subsoiling before planting on the grain yield of barley. The negative effect of subsoiling after planting was more pronounced in 1999 than in 2000, and more pronounced in spring barley. The study shows that Kemink subsoiling after planting involves a significant risk of crop damage and cannot be expected to improve crop performance in conventional soil management systems in its current form, whereas Kemink subsoiling before planting may have potential as a measure to increase yield of sugar beet and possibly other row crops too, under low nutrient input conditions.  相似文献   

12.
The effects of seed-borne Fusarium spp. and Microdochium nivale infection in spring wheat, winter wheat, and oats in Sweden was investigated in field trials for the agronomic characters yield, thousand kernel weight, grain volume weight, gluten, protein, starch, straw strength, and plant density. Seed with high and low levels of infection was mixed to obtain six infection levels in the proportions of 100/0, 80/20, 60/40, 40/60, 20/80, and 0/100 percent. The seed was untreated or treated with Celest Extra Formula M (CEFM, difenoconazole + fludioxonil) or Celest Formula M (CFM, fludioxonil). In the field trials using untreated seed, there were significant differences between infection levels only for some agronomic characters and levels. Fungicide seed treatment with CEFM in spring wheat had no significant effect on most agronomic characters including yield. In winter wheat and oats, seed treatment with CFM increased yield by 7–11% and plant density by up to 33% while having no effect on other characters. The percentage discoloration of crown roots and stem bases due to Fusarium/Microdochium spp. was also investigated visually in winter wheat and oats and found to increase with higher infection level. Fungicide seed treatment thus mainly increased plant emergence in seed lots with low-to-moderate Fusarium/Microdochium spp. infection and had little or no effects on other agronomic characters.  相似文献   

13.
An algorithm of regional assessment of the size and structure of the actual (corresponding to the modern state of ecosystems and land use patterns) and potential (for hypothetic natural ecosystems analogous to modern native ecosystems) pools of carbon has been developed and tested. A comparison between actual and potential values of carbon pools makes it possible to assess the integral result of land use in the studied region with multiple changes in the types of land use during the historical period. The calculations are made using a unified cartographic base and take into account the taxonomic position and texture of soil units, the types of modern land use, and the type and age structure of the reconstructed and actual vegetation. The results obtained for the southern taiga and forest-steppe zones of European Russian indicate that the modern actual carbon pool is 24% less than the potential carbon pool in Kostroma oblast (southern taiga zone) and 32% less than the potential carbon pool in Kursk oblast (forest-steppe zone). The actual phytomass reserves in these two regions have decreased by 40 and 75%, respectively, relative the potential phytomass reserves, so the portion of the soil carbon pool in the total carbon pool has increased. It is argues that the use of the territory for forestry and agriculture increases the role of the soil cover in sustaining the carbon budget of the region.  相似文献   

14.
Plant species differ in their potassium (K) efficiency, but the mechanisms are not clearly documented and understood. Therefore, K efficiency of spring wheat, spring barley, and sugar beet was studied under controlled conditions on a K fixing sandy clay loam. The effect of four K concentrations in soil solution ranging from low (5 and 20 μM K) to high (2.65 and 10 mM K) on plant growth and K uptake was investigated at 3 harvest dates (14, 21, and 31 days after sowing). The following parameters were determined: shoot dry matter (DM), K concentration in shoot dry matter, root length (RL), root length/shoot weight ratio (RSR), shoot growth rate/average root length ratio (GRs/aRL), K influx, and soil solution K concentrations. Wheat proved to have a higher agronomic K efficiency than barley and sugar beet, indicated by a greater relative yield under K‐deficient conditions. As compared to both cereals, sugar beet was characterized by higher K concentrations in the shoot dry matter, only 30—50 % of the root length, 15—30 % of the RSR and a 3 to 6 times higher GRs/aRL. This means that the shoot of sugar beet had a 3 to 6 times higher K demand per unit root length. Even at low K concentrations in the soil solution, sugar beet had a 7 to 10 times higher K influx than the cereals, indicating that sugar beet was more effective in removing low available soil K. Wheat and barley were characterized by slow shoot growth, low internal K requirement, i.e. high K utilization efficiency, and high RSR, resulting in a low K demand per unit root length. At low soil K concentrations, both cereals increased K influx with age, an indication of adaptation to K deficiency. The mechanism of this adaptation merits closer investigation. Model calculations were performed to estimate the K concentration difference between the bulk soil and the root surface (ΔCL) needed to drive the measured K influx. For the two cereals, the calculated ΔCL was smaller than the K concentration in the soil solution, but for sugar beet, ΔCL was up to seven times higher. This indicates that sugar beet was able to mobilize K in the rhizosphere, but the mechanisms responsible for this mobilization remain to be studied.  相似文献   

15.
The poor physical, chemical and biological properties make Stagnic Luvisol highly susceptible to water erosion on sloping terrains. The objective of this paper is to estimate the effect of different tillage treatments and crops (maize, soybean, winter wheat, spring barley, oilseed rape) on water erosion. The highest erosion in investigation period (1995–2014) was recorded in the control treatment with fallow, followed by the treatment that involved ploughing and sowing up and down the slope. Significantly, lower soil losses were recorded in no-tillage and treatments with ploughing and sowing across the slope. Regarding the crops significantly higher soil losses were recorded in spring row crops (maize and soybean) compared to high-density winter crops (wheat and oilseed rape) and double crop (spring barley with soybean). In the studied period, an average loss of 46 mm of the plough layer was recorded in the control treatment, while in treatment with ploughing and sowing up and down the slope average annual soil loss was 10 mm. According to the results of this study no-tillage and tillage across the slope are recommended as tillage which preserves soil for the next generations in agro-ecological conditions of continental Croatia.  相似文献   

16.
Chernozem-like soils with light-colored acid eluvial horizons are widespread in the forest-steppe zone of European Russia. Their formation is related to gleying under the conditions of a stagnant-percolative water regime on leached rocks. It is closely associated with the evolution of salinized soils (Gedroits’s scheme). However, these soils have not been included in the soil classifications of the Soviet Union and Russia. Based on the principles of substantial-genetic classification, one of the authors of this article [3–5, 10] referred them to gleyed podzolic chernozem-like soils, which are considered as an individual genetic soil type. With respect to agroecological aspects, they are different from the leached chernozems in their low productivity and difficulty of tillage. This article covers the problems of genesis, classification, and melioration of gleyed podzolic chernozem-like soils in the north of the forest-steppe zone of European Russia and their possible association with dark-colored podbels.  相似文献   

17.
In Northern Europe, cover crops are traditionally established before spring crops by undersowing, but some cover crops might also have an effect if preharvest sown before spring crops and even winter crops. The effects of cover crop sowing date, sowing technique and succeeding main crop on biomass production, N uptake, nitrate leaching and soil inorganic N were tested in lysimeters and in the field. Cruciferous cover crops (oil radish, white mustard) were sown preharvest by broadcasting into winter wheat in July and were allowed to grow until a following winter wheat was established in September. Other preharvest cover crops were left in place until late autumn. For comparison, the same cruciferous cover crops were established postharvest after light harrowing. Perennial ryegrass undersown in spring barley was also included. Aboveground N uptake in preharvest cover crops amounted to a maximum of 24 kg N/ha in September before sowing winter wheat. When left until late autumn, preharvest oil radish took up a maximum of 66 kg N/ha, and ryegrass and postharvest cover crops 35 kg N/ha. Preharvest establishment of cruciferous cover crops before a spring‐sown crop thus seems promising. The soil was depleted of inorganic N to the same extent in late autumn irrespective of cover crop type, sowing time and technique within winter wheat or spring barley. However, the reduction in nitrate leaching of preharvest cover crops incorporated after 2 months and followed by winter wheat was only half of that achieved by cover crops left until late autumn or spring.  相似文献   

18.
Wintergerste in der Fruchtfolge: Zuckerrüben--Sommerweizen--Wintergerste reagierte auf die mineralische N-Düngung stärker als auf die organische Düngung. Der maximale Kornertrag (5,10 t/ha) wurde bei 135 kg N/ha der organischen Düngungsvariante mit Biokompost zur Zuckerrübe erreicht. Winter barley cultivated in crop rotation: sugar beet, spring wheat, winter barley reacted more on differentiated rates of mineral nitrogen than on various organic fertilization. Winter barley yielded highest (5,10 t/ha) upon the effect of 135 kg N/ha after vermicompost application under sugar beet.  相似文献   

19.
An analogous time series of fallow ecosystems (gray soils (Luvic Phaeozems) plowed and fallowed for 2, 7, 20, 60, and more than 120 years) in the broad-leaved forest zone of Orel oblast has been analyzed. Changes in carbon pool and CO2 emission in the course of postagrogenic succession during the vegetation and winter seasons have been estimated. The restoration of ecosystems on Luvic Phaeozems follows regularities revealed in analogous studies of southern taiga Podzols and forest-steppe Chernozems. Analogously to the other studied zonal chronosequences, total annual soil respiration on Luvic Phaeozems reaches the initial level of undisturbed ecosystems simultaneously with the restoration of phytomass reserve, although significantly earlier than the organic carbon reserve in soils is restored. According to regression models, among the zonal fallows in European Russia, including the southern taiga (Podzols), mixed forests (Luvisols), broadleaved forests (Luvic Phaeozems ), forest-steppe (Chernozems) and dry steppe (Calcisol–Solonetz soil complexes), the mean annual soil respiration is maximum in the zone of gray soils and Chernozems. The increase in soil respiration under artificial wetting (Birch effect) on fallows in the broad-leaved forest zone is minimum among the studied zonal chronosequences: 1.1 ± 0.6 (no effect), which corresponds to the optimal hydrothermal conditions in this zone.  相似文献   

20.
Abstract. Leaching of nitrate from a sandy loam cropped with spring barley, winter wheat and grass was compared in a 4-year lysimeter study. Crops were grown continuously or in a sequence including sugarbeet. Lysimeters were unfertilized or supplied with equivalent amounts of inorganic nitrogen in calcium ammonium nitrate (CAN) or animal slurry according to recommended rates (1N) or 50% above recommended rates (1.5N).
Compared with unfertilized crops, leaching of nitrate increased only slightly when 1N (CAN) was added. Successive annual additions of 1.5N (CAN) or 1N and 1.5N (animal slurry) caused the cumulative loss of nitrate to increase significantly. More nitrate was leached after application of slurry because organic nitrogen in the slurry-was mineralized.
With 1N (CAN) the leaching losses of nitrate were in the following order: continuous spring barley undersown with Italian ryegrass < continuous ley of perennial ryegrass < spring barley in rotation and undersown with grass < perennial ryegrass grown in rotation = winter wheat grown in rotation < sugarbeet in rotation < continuous winter wheat < continuous barley < bare fallow.
At recommended levels of CAN (1N), cumulative nitrate losses over the four years were similar for the crops when grown in rotation or continuously. When crops received 1.5N (CAN) or animal slurry, nitrate losses from the crops grown continuously exceeded those from crops in rotation. Including a catch crop in the continuous cropping system eliminated the differences in nitrate leaching between the two cropping systems.  相似文献   

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