Deep placement of USG and dry incorporation of urea had comparable effects on tillers, straw and paddy yield, and agronomic efficiency.

nitrogen · yield · Oryza sativa (rice)Positive and negative results

1,802 papers in the same direction as this claim · 193 in the opposite direction · 49 reporting no difference from an alternative

1. negative
   Broadcast and split prilled urea left 11 to 35% of applied nitrogen unrecovered at harvest.

   Nitrogen‐15 Balance and Residual Effects of Urea‐N in Wetland Rice Fields as Affected by Deep Placement Techniques · 1984

   Opposite directionCited by this paper

2. no effect
   Basal incorporated urea gave grain yield similar to point-placed urea supergranules.

   Effect of Water Depth on Nitrogen Use Efficiency and Nitrogen‐15 Balance in Lowland Rice¹ · 1987 · compared with point‐placed urea supergranules

   No difference from an alternativeCited by this paper

3. positive
   USG in raised beds increased transplanted aman rice grain yield by up to 12.32% versus conventional prilled urea.

   Utilization of Urea Super Granule in Raised Bed Versus Prilled Urea in Conventional Flat Method for Transplanted Aman Rice (Oryza Sativa) · 2016 · compared with prilled urea (PU) broadcasting in conventional method

   Same directionCites this paper

4. negative
   Green manure and rice straw nitrogen, alone or in combination with inorganic N, gave lower grain yield, agronomic efficiency and apparent nitrogen uptake than a standard split application of prilled urea.

   Long-term Comparison of the Agronomic Efficiency and Residual Benefits of Organic and Inorganic Nitrogen Sources for Tropical Lowland Rice · 1996 · compared with a standard split application of prilled urea

   Opposite direction

5. negative
   Chaffy grain number and chaffy grain weight per 5 panicles increased significantly with enhancing nitrogen doses.

   Physiological response of rice (Oryza sativaL.) genotypes to elevated nitrogen applied under field conditions · 2014

   Opposite direction

6. negative
   Excessive nitrogen yielded 2.68–6.31% less than appropriate nitrogen application.

   Excessive Nitrogen Application Leads to Lower Rice Yield and Grain Quality by Inhibiting the Grain Filling of Inferior Grains · 2022 · compared with appropriate nitrogen application (270 kg N ha−1)

   Opposite direction

7. negative
   SCU reduced rice yield, though not significantly.

   Effects of different types of slow- and controlled-release fertilizers on rice yield · 2021

   Opposite direction

8. negative
   Preflood urea applied 14 days early yielded lowest grain yield of rice.

   Ammonia Volatilization and Nitrogen Uptake for Conventional and Conservation Tilled Dry‐Seeded, Delayed‐Flood Rice · 2007

   Opposite direction

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