Effects of N Fertilizer Sources and Tillage Practices on NH3 Volatilization, Grain Yield, and N Use Efficiency of Rice Fields in Central China

SUMMARYTopdressing of N fertilizer, whenever leaf greenness, as measured by Chlorophyllmeter (SPAD), falls below the threshold value can be used for site-specific N management in wheat cultivation. Herein, a field experiment was conducted to analyse the effect of SPAD-based N management on wheat productivity and N use efficiency during the dry season of 2010/11 and 2011/12 on acid lateritic soil of eastern India. The experiment had 12 treatments, with nine treatments combining three SPAD thresholds (38, 40 and 42) and three N levels (15, 25 and 35 kg N ha−1) as real time N management (RTNM), one fixed time N management (FTNM), one farmers’ fertilizer practise (FFP) and control (Zero N), with three replications. The grain yield of RTNM ranged from 90 to 113% as that of FTNM, but using considerably less N. Maintaining SPAD threshold of 40 up to heading stage by topdressing 25 kg N ha−1 at each time (N25S40) caused the highest grain yield (4483 kg ha−1). While saving 22.5 kg N ha−1 (18.8%), N25S40 increased agronomic N use efficiency by 58.5%, nitrogen recovery efficiency by 15.1% and partial factor productivity of applied N by 26.4% when compared with conventional fertilizer recommendations (i.e. FTNM). The SPAD-based N management strategy was found very promising in efficiently managing N fertilizer in wheat for improving wheat productivity and N use efficiency.

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Green Window Approach for improving nitrogen management by farmers in small-scale wheat fields

The Journal of Agricultural Science ◽

10.1017/s0021859614000203 ◽

2014 ◽

Vol 153 (3) ◽

pp. 446-454 ◽

Cited By ~ 7

Author(s):

X. L. YUE ◽

Y. HU ◽

H. Z. ZHANG ◽

U. SCHMIDHALTER

Keyword(s):

Plant Growth ◽

Grain Yield ◽

N Fertilizer ◽

N Use Efficiency ◽

Cereal Crops ◽

Small Scale ◽

Residual Soil ◽

Use Efficiency ◽

Window Approach ◽

N Use

SUMMARYImprovement of nitrogen (N) use efficiency is urgently needed since excessive application of N fertilizer has been widespread in small-scale fields in China, causing great losses of N fertilizer and environmental pollution. In the present study, a simple technology, termed the Green Window Approach (GWA), to optimize N strategies for cereal crops is presented. The GWA represents an on-field demonstration site visualizing the effects of incremental N levels and enables farmers to conduct such a trial within their own fields. The lowest N rate that achieves no visible change in plant growth or biomass shows the optimal N requirement of crops. Therefore the objective was to develop the key procedures of GWA and to evaluate the effects of its application in cereal crops on grain yield, N use efficiency and economic benefit. A total of seven GWA trials were performed from 2009 to 2011 on farmers’ irrigated wheat fields in the North China Plain. The GWA consisted of eight small plots placed in a compact layout on a well-accessible part of the field. Plot size varied from 2·5×2·5 to 4×4 m2, depending on the size and shape of each field. All GWA plots received basal nitrogen (N), phosphorus (P) and potassium (K) rates of 30 kg N/ha (except for the nil-N plot), 80 kg P2O5/ha and 100 kg K2O/ha. Nitrogen supplies, including residual soil nitrate in 0–90 cm determined at Zadoks growth stages (GS) 21–23 in early spring and the split-topdressing N at GS 21–23 and GS 41–52, were incrementally increased from 0 to 420 kg N/ha. The remaining part of the field still received farmers’ customary fertilization (FCF). Optimal N rate could be estimated as the lowest N rate that achieved no visible change in plant growth at GS 60–73. Compared with FCF area, grain yield was increased by 13% to a maximum or near maximum value of 5·8 t/ha, optimal N rate was sharply decreased by 69% to 116 kg N/ha, apparent N recovery was greatly increased from 11 to 46%, whereas the cost of fertilizer input was decreased by 57% to 1045 Chinese Renminbi (RMB)/ha (162 US$/ha), the profit of grain yield was increased by 13% to 12 211 RMB/ha (1891 US$/ha) and the net economic benefits were increased by 60% to 7473 RMB/ha (1157 US$/ha). Most importantly, the GWA does not need laboratory facilities, complicated procedures or professional knowledge of N balances, and farmers can easily understand and use GWA by themselves.

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Integrated nutrient, water and other agronomic options to enhance rice grain yield and N use efficiency in double-season rice crop

Field Crops Research ◽

10.1016/j.fcr.2013.04.004 ◽

2013 ◽

Vol 148 ◽

pp. 15-23 ◽

Cited By ~ 30

Author(s):

Jianquan Qin ◽

S.M. Impa ◽

Qiyuan Tang ◽

Shenghai Yang ◽

Jian Yang ◽

...

Keyword(s):

Grain Yield ◽

N Use Efficiency ◽

Rice Crop ◽

Rice Grain ◽

Use Efficiency ◽

N Use

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Nitrogen fertilization impact on agronomic traits of maize hybrids released at different decades

Pesquisa Agropecuária Brasileira ◽

10.1590/s0100-204x2001000500005 ◽

2001 ◽

Vol 36 (5) ◽

pp. 757-764 ◽

Cited By ~ 10

Author(s):

Luís Sangoi ◽

Márcio Ender ◽

Altamir Frederico Guidolin ◽

Milton Luiz de Almeida ◽

Valmor Antônio Konflanz

Keyword(s):

Grain Yield ◽

Agronomic Traits ◽

Genetic Selection ◽

N Use Efficiency ◽

Yield Potential ◽

Breeding Cycle ◽

Maize Hybrids ◽

Use Efficiency ◽

N Rates ◽

N Use

Genetic selection of maize hybrids is often conducted using high N rates during the breeding cycle. This procedure may either lead to the release of genotypes that present nitrogen luxury consumption or require a stronger N input to accomplish their yield potential. This work was carried out to evaluate the effects of N rates on grain yield and N use efficiency of hybrids cultivated in different decades in Southern Brazil. The trial was performed in Lages, Santa Catarina State. A split plot design was used. Hybrids Ag 12, Ag 28, Ag 303 and Ag 9012, released during the 60's, 70's, 80's and 90's, respectively, were evaluated in the main plots. Nitrogen rates equivalent to 0, 50, 100 and 200 kg ha-1 were side-dressed in the split-plots when each hybrid had six fully expanded leaves. Modern-day hybrid Ag 9012 had higher grain yield than hybrids of earlier eras, regardless of N rates. Under high doses of N, the older hybrids Ag 12 and Ag 28 took up more N and presented higher values of shoot dry matter at flowering than Ag 9012. Nonetheless, they set less grains per ear which contributed to decrease their grain yield and N use efficiency.

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Effects of nitrogen fertilizer application on seed yield, N uptake, N use efficiency, and seed quality of Brassica carinata

Canadian Journal of Plant Science ◽

10.4141/cjps2013-222 ◽

2013 ◽

Vol 93 (6) ◽

pp. 1073-1081 ◽

Cited By ~ 9

Author(s):

E. N. Johnson ◽

S. S. Malhi ◽

L. M. Hall ◽

S. Phelps

Keyword(s):

Seed Yield ◽

Seed Quality ◽

N Uptake ◽

Fertilizer Application ◽

Brassica Carinata ◽

N Fertilizer ◽

N Use Efficiency ◽

Use Efficiency ◽

N Rates ◽

N Use

Johnson, E. N., Malhi, S. S., Hall, L. M. and Phelps, S. 2013. Effects of nitrogen fertilizer application on seed yield, N uptake, N use efficiency, and seed quality of Brassica carinata . Can. J. Plant Sci. 93: 1073–1081. Ethiopian mustard (Brassica carinata A. Braun) is a relatively new crop in western Canada and research information on its response to N fertilizer is lacking. Two field experiments (exp. 1 at 3 site-years and exp. 2 at 4 site-years) were conducted from 2008 to 2010 in Saskatchewan and Alberta, Canada, to determine effect of N fertilizer application on Brassica carinata plant density, seed and straw yield, N uptake in seed and straw, N use efficiency (NUE), N fertilizer use efficiency (NFUE) and seed quality. N rates applied were 0 to 160 kg N ha−1 and 0 to 200 kg N ha−1 in exps. 1 and 2, respectively. Plant density was not affected by increasing N rate at 5 site-years but declined with high rates of N application at 2 site-years. Seed yield responded to applied N in 6 of 7 site-years, with the non-responsive site having a high total N uptake at the 0 kg N ha−1 rate (high Nt value). There were no sites where seed yields were maximized with the N rates applied. Response trends of straw yield and N uptake were similar to that of seed yield at the corresponding site-years. NUE and NFUE generally declined as N rate increased. Protein concentration in seed generally increased and oil concentration in seed decreased with increasing N rates. In conclusion, the responses of seed yield, total N uptake, NUE, and NFUE to applied N was similar to those reported in other Brassica species with the exception that a rate was not identified in which Brassica carinata yields were maximized.

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Significance of timing and method of N fertilizer application for the N-use efficiency in flooded tropical rice

Fertilizer Research ◽

10.1007/bf00750507 ◽

1995 ◽

Vol 42 (1-3) ◽

pp. 129-138 ◽

Cited By ~ 10

Author(s):

H. F. Schnier

Keyword(s):

Fertilizer Application ◽

N Fertilizer ◽

N Use Efficiency ◽

Use Efficiency ◽

N Use

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Improvement of Root Characteristics Due to Nitrogen, Phosphorus, and Potassium Interactions Increases Rice (Oryza sativa L.) Yield and Nitrogen Use Efficiency

Agronomy ◽

10.3390/agronomy12010023 ◽

2021 ◽

Vol 12 (1) ◽

pp. 23

Author(s):

Ming Du ◽

Wenzhong Zhang ◽

Jiping Gao ◽

Meiqiu Liu ◽

Yan Zhou ◽

...

Keyword(s):

Grain Yield ◽

Root Length ◽

N Uptake ◽

N Use Efficiency ◽

Root Characteristics ◽

Nitrogen Use ◽

Total N ◽

Absorption Area ◽

Use Efficiency ◽

N Use

Although nitrogen (N), phosphorus (P), and potassium (K) co-application improves crop growth, yield, and N use efficiency (NUE) of rice, few studies have investigated the mechanisms underlying these interactions. To investigate root morphological and physiological characteristics and determine yield and nitrogen use parameters, rhizo-box experiments were performed on rice using six treatments (no fertilizer, PK, N, NK, NP, and NPK) and plants were harvested at maturity. The aboveground biomass at the elongating stage and grain yield at maturity for NPK treatment were higher than the sum of PK and N treatments. N, P, and K interactions enhanced grain yield due to an increase in agronomic N use efficiency (NAE). The co-application of N, P, and K improved N uptake and N recovery efficiency, exceeding the decreases in physiological and internal NUE and thereby improving NAE. Increases in root length and biomass, N uptake per unit root length/root biomass, root oxidation activity, total roots absorption area, and roots active absorption area at the elongating stage improved N uptake via N, P, and K interactions. The higher total N uptake from N, P, and K interactions was due to improved root characteristics, which enhanced the rice yield and NUE.

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