T7 gave the strongest plant height, fruit number, fruit weight, fruit diameter, and fruit volume results.

2,4-D · yield · Citrus sinensis (sweet orange)Positive and negative results

12 papers in the same direction as this claim · 2 in the opposite direction

1. positive
   2, 4-D alone increased fruit retention and decreased fruit drop after June drop.

   Enhancing cropping of Navel orange by different agrochemicals foliar sprays · 2011

   Same directionCited by this paper

2. no effect
   Application of 2,4-D at full bloom had no effect on fruit diameter, fruit yield or fruit number in Citrus sinensis.

   Optimal timing of application of 2,4-D on ‘Navel’ sweet orange [Citrus sinensis(Osbeck)] reduces the size of the navel-end · 2015

   Opposite direction

3. no effect
   2, 4-D showed no definite effect on fruit set.

   Studies on the control of alternate bearing in citrus. VII · 1962

   Opposite direction

4. positive
   Early 2,4-D spray reduced summer fruit drop in all seasons.

   Growth Regulators, Fruit Drop, Yield, and Quality of Navel Orange in Florida · 1984

   Same direction

5. positive
   2,4-D gave satisfactory control of fruit drop in nearly all cases.

   Effects of 2,4-D and related substances on fruit-drop, yield, size, and quality of Washington Navel oranges · 1951

   Same direction

6. positive
   Fruit drop decreased from November through February with 16 mg/L 2,4-D.

   The influence of exogenously applied 2,4- dichlorophenoxyacetic acid on fruit drop and quality of navel oranges (Citrus sinensis L.) · 2009

   Same direction

7. positive
   2,4-D sprays reduced average Valencia orange fruit drop by 35.1 per cent.

   Effects of 2,4-D and related substances on fruit-drop, yield, size, and quality of Valencia oranges · 1952

   Same direction

8. positive
   2,4-D increased mature fruit size by 5 mm.

   Effect of 2,4-D on fruit sugar accumulation and invertase activity in sweet orange cv. Salustiana · 2015

   Same direction

6 papers more in this group

zinc sulfate · yield · Citrus sinensis (sweet orange)Results agree

8 papers in the same direction as this claim

1. positive
   Zinc sulphate at 10% anthesis significantly increased Washington navel orange fruit set through January harvest.

   PROPERLY TIMED FOLIAR FERTILIZATION CAN AND SHOULD RESULT IN A YIELD BENEFIT AND NET INCREASE IN GROWER INCOME · 2010

   Same direction

2. positive
   The highest ZnSO4 level combined with the highest CuSO4 level gave the highest shoot length, shoot diameter and number of leaves per shoot.

   Foliar Application of ZnSO4 and CuSO4 Affects the Growth, Productivity, and Fruit Quality of Washington Navel Orange Trees (Citrus sinensis L.) Osbeck · 2021

   Same direction

3. positive
   Single or combined sprays of yeast extract or zinc sulphate were very effective in stimulating Navel orange yield compared with the control.

   The beneficial effects of yeast and zinc sulphate on yield and fruit quality of Navel orange trees. · 2010 · compared with control

   Same direction

4. positive
   ZnSO4 1.00% significantly improved number of fruits in sweet orange.

   Effect of exogenous application of micronutrients on growth and yield of sweet orange CV. Blood Red · 2018 · compared with Control

   Same direction

5. positive
   The foliar micronutrient regimen yielded Fruit set of 79.81%.

   Effect of Micronutrients on Growth, Yield and Quality Parameters of Sweet Orange (Citrus sinensis L.) cv. Mosambi · 2019

   Same direction

6. positive
   Foliar ZnSO4 at 0.6% significantly improved fruit retention percent to 20.43%, compared with control (12.35%).

   Effect of micronutrients on fruit set, yield and quality of sweet orange (Citrus sinensis Osbeck) cv. Mosambi in the Gangetic alluvial region of West Bengal · 2020 · compared with control

   Same direction

7. positive
   The full micronutrient treatment recorded the maximum number of fruits per tree (379.33).

   Effect of micronutrients on growth, yield and quality of sweet orange (Citrus sinensis Osbeck) cv. Mosambi · 2017

   Same direction

8. positive
   T13 was most effective for plant height, fruit number and average fruit weight, followed by T14.

   Studies on effect of soil and foliar application of micronutrients on growth and yield parameters of sweet orange Var. Nucellar (Citrus sinensis Osbeck) · 2020 · compared with T14 Soil application of ZnSO4 @ 100 gm + MnSO4 @ 100 gm + Foliar spray of ZnSO4 @ 1% + MnSO4 @ 1%

   Same direction

nitrogen · yield · Citrus sinensis (sweet orange)Results differ

38 papers in the same direction as this claim · 8 in the opposite direction · 1 reporting no difference from an alternative

1. negative
   Soil urea reduced fruit size.

   Aggregate Effects of Nutrients and Gibberellic Acid on ‘Valencia’ Orange Crop Value1 · 1973

   Opposite direction

2. no effect
   Urea did not alter the ringing effect on orange yield.

   Effects of Ringing on Yields of Low-Bearing Orange Trees(Citrus Sinensis(L.) Osbeck) · 1971

   Opposite direction

3. negative
   N application significantly decreased fruit weight and diameter of sweet orange.

   Effect of N and Zn on ^|^lsquo;Hamlin^|^rsquo; sweet orange (Citrus sinensis Osbeck) · 1981

   Opposite direction

4. no effect
   Increased nitrogen did not reduce salinity harm to fruit production.

   Quantum efficiency of photosystem II and production of orange under salt stress and nitrogen fertilization · 2016 · compared with 100 and 200% of recommendation

   Opposite direction

5. negative
   When N and P were applied together without K, a severe antagonism resulted, with a large yield decrease.

   Nitrogen, phosphorus, potassium interactions on valencia orange yields · 1990

   Opposite direction

6. negative
   A nitrogen level of 224 kg N ha−1 reduced fruit weight compared with other N levels.

   Comparative Response of Huanglongbing-Affected Sweet Orange Trees to Nitrogen and Zinc Fertilization under Microsprinkler Irrigation · 2020 · compared with other N levels

   Opposite direction

7. no effect
   Urea treatment did not significantly change the average yield of sweet orange trees compared with control.

   Response of Sweet Orange (Citrus Sinensis Osbeck.) Plants To Zinc, Urea and Dbcp. · 1974 · compared with control

   Opposite direction

8. negative
   Orange under foliar urea produced significantly less fruit than soil nitrogen in one of three years.

   Yield of Citrus Trees with Foliar Urea as the Only N Source · 2006 · compared with soil N treatment

   Opposite direction

39 papers more in this group