Enhancing Nutrient Use Efficiencies in Rainfed Systems

Successful and sustained crop production to feed burgeoning population in rainfed areas, facing soil fertility-related degradation through low and imbalanced amounts of nutrients, requires regular nutrient inputs through biological, organic or inorganic sources of fertilizers. Intensification of fertilizer (all forms) use has given rise to concerns about efficiency of nutrient use, primarily driven by economic and environmental considerations. Inefficient nutrient use is a key factor pushing up the cost of cultivation and pulling down the profitability in farming while putting at stake the sustainability of rainfed farming systems. Nutrient use efficiency implies more produce per unit of nutrient applied; therefore, any soil-water-crop management practices that promote crop productivity at same level of fertilizer use are expected to enhance nutrient use efficiency. Pervasive nutrient depletion and imbalances in rainfed soils are primarily responsible for decreasing yields and declining response to applied macronutrient fertilizers. Studies have indicated soil test-based balanced fertilization an important driver for enhancing yields and improving nutrient use efficiency in terms of uptake, utilization and use efficiency for grain yield and harvest index indicating improved grain nutritional quality. Recycling of on-farm wastes is a big opportunity to cut use and cost of chemical fertilizers while getting higher yield levels at same macronutrient levels. Best management practices like adoption of high-yielding and nutrient-efficient cultivars, landform management for soil structure and health, checking pathways of nutrient losses or reversing nutrient losses through management at watershed scale and other holistic crop management practices have great scope to result in enhancing nutrient and resource use efficiency through higher yields. The best practices have been found to promote soil organic carbon storage that is critical for optimum soil processes and improve soil health and enhance nutrient use efficiency for sustainable intensification in the rainfed systems

The effect of partially acidulated phosphate rock on maize grain yield under monoculture growth

Kukurydzę uprawiano w latach 2003-2007 w monokulturze w gospodarstwie zlokalizowanym w Nowej Wsi Królewskiej (52o26’ N; 17o57’ E). Dwuczynnikowe doświadczenie założono na glebie lekko kwaśnej, średnio zasobnej w przyswajalny fosfor. Czynnikami doświadczalnymi były: 1) formulacja chemiczna nawozu (superfosfat prosty – SSP, superfosfat potrójny – TSP, częściowo rozłożony fosforyt – PAPR oraz kontrola – bez P), 2) dawka azotu (80 i 140 kg N·ha-1). Plonotwórcze działanie TSP i PAPR (w dawce 26,4 kg P·ha-1) niezależnie od poziomu nawożenia azotem było takie samo. Średnie efektywności agronomiczne fosforu (EA-P) dla TSP wynosiły 13,2 i 19,1 kg·kg-1 (odpowiednio dla 80 i 140 kg N·ha-1), a dla PAPR 14,4 i 17,8 kg·kg-1. Częściowo rozłożony fosforyt może być więc alternatywnym źródłem fosforu dla kukurydzy uprawianej na ziarno. Wpływ siarki z SSP na plon kukurydzy był większy po zastosowaniu mniejszej dawki azotu. Brak fosforu w dawce nawozowej (kontrola bez P) wiązał się z obniżeniem plonu ziarna w zakresie 9-15%. Brak nawożenia fosforem skutkował mniejszą liczbą ziarniaków w kolbie i mniejszą masą 1000 ziarniaków.Maize was grown in monoculture throughout the consecutive years 2003-2007 in Nowa Wieś Królewska (52o26’ N; 17o57’ E). A two factorial field experiment was established on a slightly acidic soil, moderately rich in available phosphorus. Experimental factors were as follows: 1) chemical formulation of the fertilizer (simple superphosphate – SSP, triple superphosphate – TSP, partially acidulated phosphate rock – PAPR), 2) nitrogen rate: 80 and 140 kg N·ha-1. A phosphorus unfertilized treatment (control) was also considered. The yield forming effect of TSP and PAPR (at the rate 26.4 kg P·ha-1) was similar, irrespective of nitrogen fertilization. Mean agronomical efficiencies of phosphorus (AE-P) for TSP amounted to 13.2 and 19.1 kg·kg-1, respectively for 80 and 140 kg N·ha-1, whereas in the case of PAPR, 14.4 and 17.8 kg·kg-1. respectively. In relation to calcium phosphate from superphosphate, the partially acidulated phosphate rock may be considered as an alternative source of phosphorus for maize grown for grain. The influence of sulphur from SSP on maize grain yield was higher after the application of the lowest nitrogen rate. The deficiency of phosphorus in the control treatment has led to a grain yield decrease in the order 9-19% as a result of both the low number of kernels per cob and the weight of 1000 kernels (TKW)

Wpływ formy nawozu fosforowego na pobranie i efektywność azotu w uprawie kukurydzy na ziarno

The aim of the paper was to evaluate the efficiency of nitrogen from ammonium saltpeter as related to the formulation of phosphorus fertilizer under maize grain cropping. Maize was grown in monoculture throughout the consecutive years 2003- -2007. A two factorial field experiment was established at a farm located in Nowa Wieś Królewska (52o26’ N; 17o57’ E) on a slightly acidic soil, moderately rich in phosphorus. Experimental factors were as follows: (i) chemical formulation of the fertilizer, (partially acidulated phosphate rock – PAPR, simple superphosphate – SSP and triple superphosphate – TSP), (ii) nitrogen rate: 80 and 140 kg N·ha-1; a phosphorus unfertilized treatment was also considered. The type of phosphorus fertilizer did not differentiate nitrogen uptake, but the lack of phosphorus at the applied rate has induced a decrease in nitrogen accumulation in the aboveground biomass, on average by 8%. Phosphorus fertilization at the rate 26.4 kg P·ha-1 was the main determinant of nitrogen uptake by the kernels. Nitrogen recovery (R) from the fertilizers as well as its agronomical (AE) and physiological (PE) efficiency were significantly lower in treatments where phosphorus was not applied. Furthermore, it was found a positive effect of sulphur from simple superphosphate on the AE after the application of 80 kg N·ha-1. The R values did not depend on the chemical formulation of phosphorus in the fertilizer and amounted on average to 74 and 59% for the rates 80 and 140 kg N·ha-1, respectively, whereas for the treatment without P, these values varied within the range 46-54%.Celem pracy była ocena efektywności azotu z saletry amonowej w zależności od formy nawozu fosforowego w uprawie kukurydzy przeznaczonej na ziarno. Kukurydzę uprawiano w latach 2003-2007 w monokulturze. Dwuczynnikowe doświadczenie założono w gospodarstwie zlokalizowanym w Nowej Wsi Królewskiej (52o26’ N; 17o57’ E), na glebie lekko kwaśnej, średnio zasobnej w przyswajalny fosfor. Czynniki doświadczalne: (i) formulacja chemiczna nawozu (częściowo rozłożony fosforyt – PAPR, superfosfat prosty – SSP oraz superfosfat potrójny – TSP), (ii) dawka azotu (80 i 140 kg N·ha-1); analizowano także wariant bez nawożenia fosforem. Forma nawozu fosforowego nie różnicowała pobrania azotu, natomiast brak fosforu w dawce nawozowej prowadził do zmniejszenia akumulacji azotu w biomasie nadziemnej średnio o 8%. Nawożenie fosforem w dawce 26,4 kg P·ha-1 determinowało pobranie azotu przez ziarniaki. Wykorzystanie azotu z nawozów (W) oraz efektywność agronomiczna (EA) i fizjologiczna (EF) tego składnika były istotnie mniejsze w warunkach braku nawożenia fosforem. Potwierdzono dodatnie działanie siarki z superfosfatu prostego na EA po zastosowaniu 80 kg N·ha-1. Wartości W nie zależały od formulacji chemicznej fosforu w nawozie i wynosiły średnio 74 i 59% odpowiednio dla dawek 80 i 140 kg N·ha-1, a na kontroli (bez P) wahały się w granicach 46-54%

Rola miedzi w nawozeniu pszenicy ozimej. Czesc II. Gospodarka azotem

Pszenicę ozimą nawożono dolistnie miedzią w formie wodorotlenku i siarczanu miedzi. Nawożenie wykonano w fazie krzewienia (EC 25), na początku strzelania w źdźbło (EC 31) oraz w obu terminach (EC 25 i EC 31). Całkowitą zawartość azotu w materiale roślinnym oznaczono metodą Kjeldahla w okresie kwitnienia (EC 65) oraz w fazie dojrzałości pełnej (EC 91). Nawożenie miedzią zwiększało efektywność agronomiczną i fizjologiczną azotu z saletry amonowej. Wykorzystanie azotu z nawozów było największe w warunkach stosowania wodorotlenku miedzi. Na obiektach nawożonych miedzią rośliny intensywniej przemieszczały azot z liści i słomy do ziarniaków. W wariantach z wodorotlenkiem miedzi mobilność azotu w roślinie była większa niż po zastosowaniu siarczanu miedzi. Dolistne nawożenie miedzią wykonane w okresie krzewienia i na początku strzelania w źdźbło w formie wodorotlenku i siarczanu miedzi prowadziło do zwiększenia efektywności nawożenia azotem. Rośliny nawożone miedzią sprawniej przemieszczały azot z organów wegetatywnych do ziarniaków, przy czym intensywność tego procesu była większa w warunkach stosowania wodorotlenku miedzi.Winter wheat was foliar fertilized with copper applied as copper hydroxide and sulphate at the spreading (EC 25), at beginning of shooting (EC 31) and twice, in both phases (EC 25 + EC 31). Total nitrogen was determined by the Kjeldahl method for the following growth stages: at flowering (EC 65) and grain maturity (EC 91). Foliar copper application increased the agronomic and physiological efficiency of ammonium saltpeter. Utilization of the nitrogen from fertilizers was more intensive in plants receiving copper in form of hydroxide. On the objects with copper fertilization it was found that the plants more efficiently translocated nitrogen from leaves and stems to grain. The highest dislocation of nitrogen was observed for copper hydroxide applied at spreading phase

Rola miedzi w nawozeniu pszenicy ozimej. Czesc I. Plon i jakosc ziarna

W badaniach prowadzonych na glebie ubogiej w miedź, określono wpływ dolistnego nawożenia miedzią na plon i jakość ziarna pszenicy ozimej. Nawożenie wykonano w formie siarczanu miedzi (CuSO₄·5 H₂O) oraz w formie wodorotlenku miedzi (Cu(OH)₂), w dawkach wynoszących odpowiednio 0,50 i 0,25 kg·ha⁻¹ Nawozy stosowano: (i) w fazie krzewienia (EC 25), (ii) na początku strzelania w źdźbło (EC 31) oraz (iii) w obu terminach (EC 25 i EC 31). Nawożenie miedzią zwiększało plon ziarna pszenicy ozimej w każdym roku badań. W porównaniu z siarczanem miedzi, większe działanie plonotwórcze wykazał wodorotlenek miedzi, a uzyskane zwyżki plonów związane były z gęstością łanu oraz większą liczbą ziarniaków w kłosie. Termin wykonania oprysku nie różnicował plonu ziarna pszenicy, lecz w przypadku siarczanu miedzi największe efekty plonotwórcze uzyskano po dwukrotnej aplikacji nawozu. Największą zawartość glutenu w ziarnie uzyskano, gdy dokarmianie miedzią wykonano w fazie pierwszego kolanka (EC 31), w formie wodorotlenku miedzi.Investigations were carried out on copper deficient soils to evaluate the quantitative influence of foliar fertilization with copper on winter wheat grain yield and quality. Copper was applied as sulphate (CuSO₄·5 H₂O) and hydroxide (Cu(OH)₂) at rates 0.50 and 0.25 kg·ha⁻¹, respectively. The fertilizers were applied: (i) at the spreading phase (EC 25), (ii) at the beginning of shooting (EC 30-31) and (iii) twice (EC 25 and EC 31). Copper fertilization affected the yields of winter wheat grain which increased over consecutive years of investigations. Higher efficiency was obtained in case of copper applied as hydroxide than as the sulphate, and yield increase depended on the number of ears per area unit and number of grain per ear. Time of foliar fertilization did not differentiate the yield of winter wheat grain, but in case of copper sulphate better yielding effects were obtained after its twofold application. Best grain quality higher gluten content was observed in variant with copper fertilization at the beginning of shooting stage (EC 31)

Wpływ wzrastających dawek azotu na przebieg krzywej krytycznej koncentracji azotu w pszenicy ozimej w okresie wzrostu wegetatywnego

Nitrogen is the dominant factor affecting the rate of wheat growth and yielding. Water supply during the critical stages of yield component formation is a factor limiting nitrogen use efficiency. A study dealing with this problem has been conducted, based on a long-term field experiment with four N levels (0, 60, 120, 180 kg N ha -1 ) against the background of four systems of potassium management, including: medium and high K soil fertility levels without and with K fertilizer (MK-, MK+, HK-, HK+). The objective of the study was to evaluate the wheat nitrogen nutritional status during the vegetative period of wheat growth according to nitrogen concentrations in leaves and stems. The research was run in 2003, with severe deficit of water, and in 2004, under semi-dry water conditions. Grain yield of wheat responded to both experimental factors only in 2004. Nitrogen concentration in plant parts was dependent only on N doses, thus underlying good adaptation of wheat to the seasonal course of water supply. Nitrogen concentration in leaves followed the quadratic regression model. This type of response indicates an N saturation status, i.e. a non-limiting effect of this factor on plant growth. The pattern of N concentration in stems was in accordance with the linear regression model. This type of response indicates the N-limited growth due to an insufficient supply of nitrogen. The Critical Nitrogen Concentration (CNC) pattern showed significant adaptability of wheat to N fertilizer levels. The Nitrogen Nutrition Index, calculated from the CNC, can serve as an indicator of N dilution during the vegetative period of wheat growth

Przemiany zwiazkow fosforu w glebie w zaleznosci od systemu nawozenia w przeszlosci

W pracy wykorzystano gleby przez dwadzieścia lat nawożone mineralnie (NPK), w których fosfor stosowano w dawkach wynoszących 11 kg P·ha⁻¹ oraz gnojowicą (GN) w ilości 25 m³·ha⁻¹. Każdą z gleb inkubowano w stałej temperaturze przez 224 dni z dodatkiem fosforu mineralnego (w formie KH₂PO₄, w dawce 50 µg·g⁻¹ gleby) oraz bez fosforu (kontrola). Analizie poddano gleby w 0, 28 i 224 dniu inkubacji. W glebach nawożonych w przeszłości gnojowicą zanotowano trend do zwiększania się ilości fosforu w połączeniach z wapniem (P-Ca), kosztem frakcji P-Al. Frakcja fosforu rozpuszczalnego w glebie (P-lab.) stanowiła od 0,9 do 2,5% fosforu mineralnego. W okresie inkubacji największemu zróżnicowaniu podlegały frakcje fosforu P-Al oraz wodnorozpuszczalnego (P-lab.). W glebie nawożonej w przeszłości gnojowicą (GN), dodany fosfor mineralny stymulował mineralizację fosforu organicznego do 28 dnia inkubacji, lecz po zakończeniu eksperymentu nastąpiła immobilizacja fosforu mineralnego. W systemie nawożenia opartym o nawozy mineralne (NPK) dynamika przemian świeżo wprowadzonych fosforanów była mniejsza. Uwalniany w czasie inkubacji fosfor mineralny akumulował się w puli fosforu związanego z glinem (P-Al) oraz w formach wo- dnorozpuszczalnych (P-lab.), określanych mianem najlepiej przyswajalnych przez rośliny. Bieżące nawożenie fosforem wymaga uwzględnienia systemu nawo żeniąSoils investigated in the current work were collected in field trials carried out for 20 years, where phosphorus was applied as follows: mineral form (NPK) at 11 kg P·ha⁻¹, and cattle slurry - (GN) at 25 m³·ha⁻¹. Each soil was incubated at a constant temperature for 224 days and two operational treatments were established: with mineral phosphorus (KH₂PO₄, at the rate 50 µg·g⁻¹ soil) and without phosphorus (control). Chemical analyses were performed for soil samples collected at the following dates: 0, 28 and 224 days of incubation. A tendency was found to increase the amounts of phosphorus bound with calcium (P-Ca) as compared to the P-Al fraction for soils receiving cattle slurry in the past. The fraction of water soluble phosphorus in the soil (P-lab.) represented from 0.9 to 2.5% of mineral P. Water soluble (P-lab.) and P-Al fractions were found to be strongly differentiated during the period of incubation. In the treatment with cattle slurry (GN), the added mineral phosphorus stimulated the mineralization of soil organic phosphorus up to the 28th day of incubation, but phosphorus immobilization took place at the end of in the incubation. In the case of the NPK treatments, the transformation of newly incorporated phosphates was weaker. Mineral phosphorus released during the incubation time was accumulated in the pool of phosphorus bound with aluminum (P-Al) and water soluble forms (P- lab.) with the latter ones considered as the P readily available for plants. Current phosphorus fertilization should be based on the fertilization system applied in the past, which modulated soil phosphorus transformation and influences the availability of phosphorus from fertilizers

Impact of increasing nitrogen doses on the course of a nitrogen critical concentration curve during the vegetative growth of winter wheat

Nitrogen is the dominant factor affecting the rate of wheat growth and yielding. Water supply during the critical stages of yield component formation is a factor limiting nitrogen use efficiency. A study dealing with this problem has been conducted, based on a long-term field experiment with four N levels (0, 60, 120, 180 kg N ha -1 ) against the background of four systems of potassium management, including: medium and high K soil fertility levels without and with K fertilizer (MK-, MK+, HK-, HK+). The objective of the study was to evaluate the wheat nitrogen nutritional status during the vegetative period of wheat growth according to nitrogen concentrations in leaves and stems. The research was run in 2003, with severe deficit of water, and in 2004, under semi-dry water conditions. Grain yield of wheat responded to both experimental factors only in 2004. Nitrogen concentration in plant parts was dependent only on N doses, thus underlying good adaptation of wheat to the seasonal course of water supply. Nitrogen concentration in leaves followed the quadratic regression model. This type of response indicates an N saturation status, i.e. a non-limiting effect of this factor on plant growth. The pattern of N concentration in stems was in accordance with the linear regression model. This type of response indicates the N-limited growth due to an insufficient supply of nitrogen. The Critical Nitrogen Concentration (CNC) pattern showed significant adaptability of wheat to N fertilizer levels. The Nitrogen Nutrition Index, calculated from the CNC, can serve as an indicator of N dilution during the vegetative period of wheat growth