NAWOŻENIE RZĘDOWE BURAKA CUKROWEGO (BETA VULGARIS L.) WIELOSKŁADNIKOWYM NAWOZEM PŁYNNYM NA BAZIE ROZTWORU SALETRZANOMOCZNIKOWEGO JAKO CZYNNIK ZWIĘKSZAJĄCY EFEKTYWNOŚĆ AZOTU

Sugar beet is the main crop commonly cultivated for sugar production in temperate regions of the World. Actual yields in main Central Europe producing countries are much lower, due to many limiting factors. Among them, nutrients supply is of great value, especially referring to efficiency of nitrogen, which is generally low. In the conducted study two methods of nitrogen application were compared (i) broadcast of calcium saltpeter and (ii) row application of the multicomponent fertilizer based on urea-ammonium-nitrate (UAN) solution. The basic amount of the applied N was 75 kg ha-1. The highest yields of both taproots and refined sugar were harvested on the plot receiving 75 kg N-1 as UAN liquid multicomponent fertilizer and 50% of the recommended P and K rates. The positive effects of row application of liquid N fertilizer on taproot and sugar yields were also corroborated by high values of indices of agronomic efficiency for both N as well as P and K. However this method of sugar beets fertilization has some possibilities, as indicated by still high contents of melassogenic substances.Burak cukrowy jest podstawowym surowcem do produkcji cukru w strefie klimatu umiarkowanego. W krajach centralnej Europy, w których uprawia się buraki cukrowe, aktualny poziom plonowania tej rośliny znacznie odbiega od potencjalnych możliwości. Wśród różnych przyczyn takiego stanu rzeczy, koniecznie należy wymienić małą efektywność nawożenia azotem. W badaniach własnych porównano dwie metody nawożenia azotem: i) rzutowe - saletrą wapniową oraz ii) rzędowe - wieloskładnikowym nawozem otrzymanym na bazie roztworu mocznika i saletry amonowej (UAN). Podstawowa dawka azotu, niezależnie od przyjętego systemu, wynosiła 75 kg ha-1. Największy plon korzeni, i plonu cukru technologicznego, uzyskano przy jednoczesnym zastosowaniu 75 kg N kg-1 w formie wieloskładnikowego nawozu płynnego (UAN) oraz 50% rekomendowanej dawki fosforu oraz potasu. Pozytywny efekt nawożenia rzędowego na plon korzeni i cukru wynikał ze wzrostu efektywności agronomicznej zarówno azotu, jak i zastosowanego równocześnie P i K

MODELE KONSUMPCJI NAWOZÓW MINERALNYCH W KRAJACH EUROPY CENTRALNEJ – WPŁYW NA TRENDY PLONÓW RZECZYWISTYCH W LATACH 1986- 2005 – ANALIZA PORÓWNAWCZA REPUBLIKI CZESKIEJ I POLSKI

This study outlines the long-term trends of fertilizers consumption in the Czech Republic and Poland and their impact on actual yield development of main crops for the period 1986-2005. In both countries dynamics of N, P, K fertilizers use showed analogical trends. Based on amounts and nutrient ratio of consumed fertilizer, as expressed as P2O5:N and K2O:N ratios, there were distinguished three phases of fertilizers use: i) high ii) collapse and iii) restoration/stagnation. The stagnation phase was attributed for P and K in the Czech Republic. The observed yield depressions since the 1990s reflect changes in farmer’s long-term fertilization and has been termed a temporary yield gap (TYG). However, its long-term existence negatively affects crop production stability. The development of new, country specific strategies in the management of P and K, i.e. adopted to natural soil fertility conditions, is a main goal of present agriculture of both countries, compared in the presented study.Przeprowadzone badania przedstawiają długoterminowe trendy zużycia nawozów mineralnych w Republice Czeskiej i w Polsce oraz ich wpływ na trendy plonów rzeczywistych, roślin uprawnych w okresie 1986-2005. W obu krajach w tym okresie dynamika zużycia nawozów N, P i K przebiegała analogicznie. Na podstawie ilości stosowanych nawozów i ich struktury, przedstawionych jako stosunki P2O5:N i K2O:N, wyróżniono trzy, zmienne w długości, fazy konsumpcji : i) dużej ii) załamanie, iii) restaurację/stagnację. Stan stagnacji odnotowano dla P i K tylko w Czechach. Depresję plonów roślin uprawnych, ujawnioną z początkiem lat 90-tych a odzwierciedlająca zmiany w strategii nawożenia, określono terminem tymczasowa redukcja plonów (TRP). Wieloletnia trwałość tego stanu wpływa jednak ujemnie na stabilność produkcji roślinnej. Budowa nowych strategii gospodarki P i K, dostosowanych do warunków naturalnych, to znaczy warunków naturalnej żyzności gleby, jest zatem głównym zadaniem obu porównywanych w tym opracowaniu krajów

Determination of Mehlich 3 extractable elements with visible and near infrared spectroscopy in a mountainous agricultural land, the caucasus mountains

Soil spectroscopy is a promising alternative to evaluate and monitor soil and water quality, particularly in mountainous agricultural lands characterized by intense degradation and limited soil tests reports; a few studies have evaluated the feasibility of VIS-NIR spectroscopy to predict Mehlich 3 (M3) extractable nutrients. This study aimed to (i) examine the potential of VIS-NIR spectroscopy in combination with partial least squares regression to predict M3-extractable elements (Ca, K, Mg, P, Fe, Cd, Cu, Mn, Pb, and Zn) and basic soil properties (clay, silt, sand, CaCO3, pH, and soil organic carbon-SOC), (ii) find optimal pre-processing techniques, and (iii) determine primary prediction mechanisms for spectrally featureless soil properties. Topsoil samples were collected from a representative area (114 samples from 525 ha) located in the mountainous region of NW Azerbaijan. A series of pre-processing steps and transformations were applied to the spectral data, and the models were calibrated and evaluated based on the coefficient of determination (R2), root mean square error (RMSE), and the residual prediction deviation (RPD). The leave-one-out cross-validated predictions showed that the first derivative spectra produce higher prediction accuracies (R2 = 0.51–0.91; RPD = 1.20–2.29) for most soil properties. The evaluation of the model performance with optimal pre-processing techniques revealed that both calibration and validation models produce considerable differences in RPD values associated with sample size and the random partition of the calibration or validation subsets. The prediction models were excellent or very good (RPD > 2.0) for CaCO3, SOC, sand, silt, Ca, and Pb, good or fair (1.4 < RPD < 2.0) for clay, K, Cd, pH, Fe, Mn, and Cu, and poor (1.0 < RPD < 1.4) for Mg, P, and Zn. Principal component and correlation, stepwise regression analysis, and variable importance in projection procedures allowed to elucidate the underlying prediction mechanisms. Unlike the previous studies, the spectral estimations of pH, Ca, Mg, P, Fe, Pb, and Cd concentrations were linked to their correlation with CaCO3 rather than soil organic matter, whereas Mg and P concentrations were also connected to Fe-oxides. Soil particle sizes contributed to predicting K concentration but confounded the prediction of P and Zn concentration. The weaker correlations of Mn, Cu or Zn with CaCO3, particle sizes, SOC, Fe, and spectral data yielded to their lower prediction accuracy. The major prediction mechanisms for M3-extractable elements relied on their relations with CaCO3, pH, clay content and mineralogy, and exchangeable cations in the context of their association with land use. The results can be used in mountain lands to evaluate and control the effect of management on soil quality indices and land degradation neutrality. Further studies are needed to develop most advantageous sampling schemes and modeling.Publikationsfonds ML

Site-Specific Nutrient Management

The editorial introduces to a Special Issue entitled ”Site-Specific Nutrient Management. The concept of the nitrogen gap (NG) is as a core challenge for an effective realization of the so called “twin objectives” in sustainable agriculture. This special issue stresses on some hot spots in crop production, being responsible in the yield gap development, that farmers have to take control. The yield gap cannot be ameliorated without the synchronization of the in-season requirements of the currently grown crop for N with its three-dimensional variability in a supply on a field (temporal, spatial and vertical). A recognition of soil fertility status in the rooted zone, which includes availability of both mineral N and nutrients decisive for its uptake, is the first step in the NG amelioration. The sustainability in soil fertility, as a prerequisite of N fertilizer application, requires a wise strategy of organic matter management, based on farmyard manure, and/or cultivation of legumes. The soil fertility status, irrespectively of the World region determines ways of the N rate optimization. The division of a particular field into homogenous productive units is the primary step in the NG cover. It can be delineated, using both data on soil physico-chemical properties of the soil rooted zone, and then validated by using satellite spectral images of the crop biomass in a well-defined stage of its growth, decisive for yield. The proposed set of diagnostic tools is a basis for elaboration an effective agronomic decision support system

Deficiencies of Secondary Nutrients in Crop Plants&mdash;A Real Challenge to Improve Nitrogen Management

Secondary nutrient (e.g., calcium, magnesium, sulfur) deficiencies in crop plants disturb the nitrogen balance in the plants, thus reducing the overall yield. This hypothesis was analyzed based on the physiological functions of these nutrients, in relation to the uptake and utilization of N, in crop plants. Nitrogen uptake by plants requires a well-developed root system, the size of which depends on the supply of calcium. This process is largely controlled by the content of toxic aluminum in the soil, which can be mitigated through the application of lime and/or gypsum. In humid climates, the excessive uptake of calcium by plants occurs during water shortages; this process significantly interferes with N uptake. Magnesium, which affects plant growth throughout the growing season, can effectively control excessive calcium uptake. Magnesium deficiency can be ameliorated with soil- or foliar-applied fertilizers. These stages define the timing of plant sampling and determination of the N:S ratio, as an indicator of plant nutritional status. The application of Mg, S, or MgS facilitates higher productivity of fertilizer N by narrowing the N:Mg and N:S ratios in plants. The use of secondary nutrients can allow farmers to obtain high yields while reducing both production costs and environmental risks

Effect of Magnesium Fertilization Systems on Grain Yield Formation by Winter Wheat (Triticum aestivum L.) during the Grain-Filling Period

The application of magnesium significantly affects the components of the wheat yield and the dry matter partitioning in the grain-filling period (GFP). This hypothesis was tested in 2013, 2014, and 2015. A two-factorial experiment with three rates of magnesium (0, 25, 50 kg ha&minus;1) and four stages of Mg foliar fertilization (without, BBCH 30, 49/50, two-stage) was carried out. Plant material collected at BBCH: 58, 79, 89 was divided into leaves, stems, ears, chaff, and grain. The wheat yield increased by 0.5 and 0.7 t ha&minus;1 in response to the soil and foliar Mg application. The interaction of both systems gave + 0.9 t ha&minus;1. The Mg application affected the grain yield by increasing grain density (GD), wheat biomass at the onset of wheat flowering, durability of leaves in GFP, and share of remobilized dry matter (REQ) in the grain yield. The current photosynthesis accounted for 66% and the REQ for 34%. The soil-applied Mg increased the REQ share in the grain yield to over 50% in 2014 and 2015. The highest yield is possible, but provided a sufficiently high GD, and a balanced share of both assimilate sources in the grain yield during the maturation phase of wheat growth

Yield Predictive Worth of Pre-Flowering and Post-Flowering Indicators of Nitrogen Economy in High Yielding Winter Wheat

Indicators of nitrogen economy in winter wheat during vegetative development are a reliable tool for yield prognosis. This hypothesis was verified in a field experiment, carried out in the 2013/2014, 2014/2015, and 2015/2016 seasons. The field experiment, in a two-factor split-plot design, included the following systems of wheat protection (CFP): (i) N + micronutrients, (ii) N + fungicides, (iii) N + micronutrients + fungicides; and N rates: 0, 40, 80, 120, 160, 200, 240 kg N ha−1. The content and accumulation of N in wheat at the beginning of stem elongation and at heading were used for grain density and yield prediction. In the grain-filling phase, the stem N acted as a buffer, stabilizing yield at a high level. The condition for such action was the stem N equilibrium with the ear N at flowering. The N depletion from the leaves during the grain-filling period significantly depended on the grain density. The post-flowering uptake of N by wheat was affected by the grain density, which was affected by the N reserves in the stem. Yield forecast based on pre-flowering indices of nitrogen economy in cereals affects both agronomic decisions aimed at correcting the nutritional status of plants, and farm economics

Magnesium Fertilization Increases Nitrogen Use Efficiency in Winter Wheat (<i>Triticum aestivum</i> L.)

Wheat fertilized with Mg, regardless of the method of application, increases nitrogen fertilizer (Nf) efficiency. This hypothesis was tested in 2013, 2014, and 2015. A two-factorial experiment with three doses of Mg (i.e., 0, 25, and 50 kg ha−1) and two stages of Mg foliar fertilization (without; BBCH 30; 49/50; 30 + 49/50) was carried out. Foliar vs. in-soil Mg fertilization resulted in a comparable grain yield increase (0.5–0.6 t ha−1). The interaction of both fertilization systems increased the yield by 0.85–0.9 t ha−1. The booting/heading phase was optimal for foliar fertilization. Mg accumulation by wheat fertilized with Mg increased by 17% compared to the NPK plot. The recovery of foliar Mg was multiple in relation to its dose. The recovery of the in-soil Mg applied ranged from 10 to 40%. The increase in yield resulted from the effective use of N taken up by wheat. In 2014 and 2015, this amount was 21–25 kg N ha−1. The increase in yield resulted from the extended transfer of N from vegetative wheat parts to grain. Mg applied to wheat, irrespective of the method, increased the efficiency of the N taken up by the crop. Mg fertilization resulted in higher Nf productivity, as indicated by the increased nitrogen apparent efficiency indices