Ammonia volatilization losses from prilled urea, urea supergranules (USG) and coated USG in rice fields

SUMMARYA field experiment was made during the rainy season of 1982 and 1983 at the Indian Agricultural Research Institute, New Delhi to study the relative efficiency of prilled urea, urea supergranules (USG) and USG coated with neem cake and DCD. Prilledurea was applied at 60, 120 and 180 kg N/ha, while the other sources of N were applied only at 120 kg N/ha. Nitrogen was added to rice in a single application 20 days after sowing (20 DAS) or in two applications, half 20 DAS and the rest at panicle initiation. Response of rice to prilled urea was linear up to 180 kg N/ha, the highest dose in the present study. Two applications produced more rough rice and straw and resulted in higher nitrogen uptake and apparent recovery than a singleapplication. Neem-cakecoated USG was superior to prilled urea in respect of panicle characters, rough rice and straw yield, nitrogen uptake and apparent nitrogen recovery. Coating USG with DCD also showed some advantage. Uncoated USG was only slightly better than prilled urea.

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Comparative Effects of the Application of Prilled Urea and Urea Supergranules on Flooded Rice in Madagascar

Journal of Agricultural Studies ◽

10.5296/jas.v6i1.12741 ◽

2018 ◽

Vol 5 (4) ◽

pp. 218

Author(s):

Guido D’Onofrio ◽

Jacques Dupuy ◽

Rémi Gaudin

Keyword(s):

Nitrogen Utilization ◽

Urea Nitrogen ◽

The Real ◽

Urea Supergranules ◽

Flooded Rice ◽

Prilled Urea ◽

Aerial Parts

Applying urea supergranules to flooded rice (10 cm deep, 3 weeks after transplantation) is associated with yield increases of 17%, 23%, 22% and 16% (for doses of 27, 54, 81 and 108 units of nitrogen per hectare) compared with prilled urea. Nitrogen-15 can be used to establish the real nitrogen utilization coefficients for the aerial parts of the plant. While the figures are very low for prilled urea (between 4% and 9%), they exceed 25% and 38% for supergranules on the sites studied. The effect of fertilizer form is greater than the dosage factor. The results are discussed in terms of apparent utilization coefficients and mechanism used.

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Reduction of Ammonia Volatilization from Urea by a Floating Duckweed in Flooded Rice Fields

Soil Science Society of America Journal ◽

10.2136/sssaj2008.0230 ◽

2009 ◽

Vol 73 (6) ◽

pp. 1890-1895 ◽

Cited By ~ 15

Author(s):

Hua Li ◽

Xinqiang Liang ◽

Yanfeng Lian ◽

Lei Xu ◽

Yingxu Chen

Keyword(s):

Ammonia Volatilization ◽

Rice Fields ◽

Flooded Rice

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Ammonia volatilization from rice fields in alkaline soil as influenced by soil moisture and nitrogen

The Journal of Agricultural Science ◽

10.1017/s0021859600085087 ◽

1989 ◽

Vol 112 (2) ◽

pp. 185-190 ◽

Cited By ~ 5

Author(s):

R. B. Singandhupe ◽

R. K. Rajput

Keyword(s):

Soil Moisture ◽

Ammonia Volatilization ◽

Rice Fields ◽

Alkaline Soil ◽

Moisture Regimes

SummaryVolatilization of ammonia from urea applied to rice on a soil of pH 9·3 was measured during 1982 and 1983 at Karnal. For three moisture regimes (continuous submergence, and irrigation 1 day and 4 days following subsidence of ponded water) mean ammonia losses varied from 28·2 to 31·8 kg N/ha. For urea applications between 40 and 120 kg N/ha, mean ammonia losses varied from 26.1 to 33.7 kg N/ha. Ammonia losses were highest on the second day following urea application and dropped to near zero 7–8 days after application.

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