Effect of Planting Methods and Nitrogen Sources on Yield, Yield Components and N-Uptake of Spring Maize

AbstractNitrogen (N) is a limiting nutrient in vast regions of the world’s oceans, yet the sources of N available to various phytoplankton groups remain poorly understood. In this study, we investigated inorganic carbon (C) fixation rates and nitrate (NO3−), ammonium (NH4+) and urea uptake rates at the single cell level in photosynthetic pico-eukaryotes (PPE) and the cyanobacteria Prochlorococcus and Synechococcus. To that end, we used dual 15N and 13C-labeled incubation assays coupled to flow cytometry cell sorting and nanoSIMS analysis on samples collected in the North Pacific Subtropical Gyre (NPSG) and in the California Current System (CCS). Based on these analyses, we found that photosynthetic growth rates (based on C fixation) of PPE were higher in the CCS than in the NSPG, while the opposite was observed for Prochlorococcus. Reduced forms of N (NH4+ and urea) accounted for the majority of N acquisition for all the groups studied. NO3− represented a reduced fraction of total N uptake in all groups but was higher in PPE (17.4 ± 11.2% on average) than in Prochlorococcus and Synechococcus (4.5 ± 6.5 and 2.9 ± 2.1% on average, respectively). This may in part explain the contrasting biogeography of these picoplankton groups. Moreover, single cell analyses reveal that cell-to-cell heterogeneity within picoplankton groups was significantly greater for NO3− uptake than for C fixation and NH4+ uptake. We hypothesize that cellular heterogeneity in NO3− uptake within groups facilitates adaptation to the fluctuating availability of NO3− in the environment.

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Nitrogen and phosphorus nutrition of dryland grain sorghum at Katherine, Northern Territory. 4. 15-nitrogen studies on nitrogen carrier and method of application

Australian Journal of Experimental Agriculture ◽

10.1071/ea9790481 ◽

1979 ◽

Vol 19 (99) ◽

pp. 481 ◽

Cited By ~ 5

Author(s):

RJK Myers

Keyword(s):

Ammonium Nitrate ◽

Ammonium Sulphate ◽

Field Experiments ◽

N Uptake ◽

Poor Performance ◽

Nitrogen Sources ◽

Grain Sorghum ◽

Nitrogen And Phosphorus ◽

Significant Treatment ◽

Effective Source

The effect of nitrogen source and method of application on yield and N uptake of dryland grain sorghum was studied, using 15-nitrogen labelled fertilizers. The nitrogen sources were ammonium sulphate, ammonium nitrate and urea, and the methods were banded, mixed and split application, using a rate of 50 kg N ha-1 throughout. The experiment was conducted over two wet seasons, 1970-71 and 1971-72. Method of application increased yield and nitrogen uptake in the order banded > mixed > split. Source of nitrogen resulted in the order ammonium sulphate = ammonium nitrate > urea. In the drier season, urea behaved somewhat differently, i.e. banded urea > banded ammonium nitrate= banded ammonium sulphate. Calculation of percentage recovery in general confirmed these results. It was concluded that nitrogenous fertilizer is more effective when banded, and that urea was a less effective source of nitrogen than the two ammonium salts. The results obtained with 15-nitrogen revealed a significant treatment effect that was not apparent in non-tracer experiments namely, the poor performance of urea in the second year. Because of its greater sensitivity, and because it identifies the nitrogen derived from fertilizer, the 15-nitrogen technique has scope for use in field experiments comparing fertilizers and cultural techniques.

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Influence of Different Planting Methods and Mulching on Growth and Yield of Spring Maize (Zea mays L)

Journal of Krishi Vigyan ◽

10.5958/2349-4433.2019.00089.8 ◽

2019 ◽

Vol 8 (1) ◽

pp. 149

Author(s):

Amandeep Kaur ◽

Gurbax Singh Chhina

Keyword(s):

Zea Mays ◽

Zea Mays L ◽

Growth And Yield ◽

Planting Methods ◽

Spring Maize

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Effect of potash application on growth, yield and yield components of spring maize hybrids

Pure and Applied Biology ◽

10.19045/bspab.2015.42008 ◽

2015 ◽

Vol 4 (2) ◽

pp. 195-203

Author(s):

Asad Ali Khan

Keyword(s):

Yield Components ◽

Growth Yield ◽

Maize Hybrids ◽

Spring Maize ◽

Yield And Yield Components

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Nitrogen Sources and Rates for Direct-seeded and Transplanted Head Lettuce

HortScience ◽

10.21273/hortsci.27.3.228 ◽

1992 ◽

Vol 27 (3) ◽

pp. 228-230 ◽

Cited By ~ 1

Author(s):

J.L. Walworth ◽

D.E. Carling ◽

G.J. Michaelson

Keyword(s):

Nitrogen Sources ◽

Growing Season ◽

Field Trials ◽

Planting Dates ◽

N Application ◽

Planting Methods ◽

Application Rates ◽

Head Weight ◽

Southcentral Alaska ◽

Direct Seeded

Head lettuce (Lactuca sativa L.) cv. Salinas was produced in field trials in southcentral Alaska with varying planting dates, planting methods, N sources, and N application rates. Variables measured included head weight and diameter and harvest date. Nitrogen source had little effect on head weight. Direct-seeded lettuce produced heaviest beads from early plantings; transplants produced heaviest heads when planted in mid- to late season. Transplanting generally produced heavier heads than direct-seeding. Head weight of transplanted and direct-seeded lettuce was maximized with ≈112 kg N/ha. The data suggest that 112 kg N/ha may be suitable for lettuce direct-seeded or transplanted throughout the growing season.

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