Treatment T8 (FeSO4 + Urea) increased pods per plant to 16.32 relative to the control.

iron(2+) sulfate (anhydrous) · yield · Glycine max (soybean)Results differ

6 papers in the same direction as this claim · 1 in the opposite direction

1. no effect
   FeSO4 did not improve soybean yield.

   Iron Chelates Alleviate Iron Chlorosis in Soybean on High pH Soils · 2014

   Opposite direction

2. positive
   Spraying 0.5% FeSO4 at 30, 60 and 90 DAS gave the maximum increase in grain yield, 3064 kg/ha versus 2397 kg/ha in the control.

   Biofortification of Soybean (Glycine max L.) through FeSO4·7H2O to Enhance Yield, Iron Nutrition and Economic Outcomes in Sandy Loam Soils of India · 2022 · compared with the control

   Same direction

3. positive
   Combined soil and foliar iron application improved soybean plant height, number of branches, number of pods relative to either application alone.

   Effect of Iron Nutrition on Growth, Quality and Yield of Soybean (Glycine Max. L.) Grown on Problematic Inceptisol · 2021 · compared with only soil application or foliar spray of iron

   Same direction

4. positive
   The SSNM treatment produced maximum soybean seed yield of 27.82q ha-1.

   Effect of nutrient management approaches on seed yield and nutrient uptake of soybean-sorghum based cropping system · 2020

   Same direction

5. positive
   FeSO4 foliar spray increased soybean number of branches to 5.42 relative to other treatments and control.

   Effect of foliar applications of micronutrient and methanol on seed yield of soybean · 2016 · compared with other treatments and control

   Same direction

6. positive
   Seed yield of soybean was significantly higher under the SSNM approach targeted at 30 q ha-1 with 25 kg FeSO4 5H2O ha-1 than in the absolute control.

   Response of soil test based nutrient management approaches on growth and yield of soybean in soybean- sorghum based cropping system · 2020 · compared with absolute control

   Same direction

7. positive
   FeSO4 at 0.5% supported dry matter production and growth parameters.

   Morpho- Physio logical studies of soybean under the spraying of plant growth regulator [Glycine max (L.) Merill] · 2018

   Same direction

nitrogen · yield · Glycine max (soybean)Positive and negative results

317 papers in the same direction as this claim · 91 in the opposite direction · 7 reporting no difference from an alternative

1. negative
   Soybeans relying only on atmospheric nitrogen yielded less than half as much seed as those using nitrate and atmospheric nitrogen in hydroponics.

   Soil and Symbiotic Nitrogen Requirements for Optimum Soybean Production¹ · 1974 · compared with plants utilizing both nitrate and atmospheric nitrogen

   Opposite direction

2. no effect
   Applied nitrogen did not significantly affect grain yield; the observed increase was 39 kg ha−1.

   Nitrogen Application to Soybean at Early Reproductive Development · 2005 · compared with no‐N control

   Opposite direction

3. negative
   Nitrogen stress during seed development reduced soybean final seed size.

   The Effect of Source-Sink Alterations on Soybean Seed Growth* · 1985

   Opposite direction

4. no effect
   Soil-applied N or foliar-applied B did not increase soybean seed yield at any rate or application stage.

   Soybean Yield Response to Reproductive Stage Soil‐Applied Nitrogen and Foliar‐Applied Boron · 2001

   Opposite direction

5. no effect
   With adequate N, nodulated and non-nodulated soybean had similar seed yields.

   Dry Matter Accumulation in Soybean (Glycine max (L) Merrill) Plants As Influenced by N, P, and K Fertilization¹ · 1971 · compared with nodulated and non‐nodulated soybeans

   Opposite direction

6. no effect
   Nitrogen at rates up to 360 kg/ha added for the preceding year's corn had no effect on soybean yields.

   Soybean Yields with Direct and Residual Nitrogen Fertilization¹ · 1973

   Opposite direction

7. negative
   K-polyphosphate mix foliar spraying reduced soybean yield by 10.9% on average over two sites.

   Foliage Injury, Nutrient Intake, and Yield of Soybeans as Influenced by Foliar Fertilization¹ · 1980

   Opposite direction

8. no effect
   Straw treatment, nitrogen timing, and nitrogen rate did not significantly differ in soybean yield.

   Effect of Nitrogen on Nodulation and Yield of Irrigated Soybeans¹ · 1971

   Opposite direction

407 papers more in this group