1. Fertilizer Management
M A Saleque

2. Soil fertilization or crop fertilization
Same
Different

3. 4 R
Right source
Right Rate
Right time
Right place

4. Right place Recognize root-soil dynamics.
Manage spatial variability within the field to meet site-specific crop needs.
Movement of fertilizer nutrient.
Limit potential losses from the field.

6. Right place
TSP should be applied at the root domain because P moves very slowly in soil.
Urea should be placed at the anaerobic layer to reduce volatilization loss.

7. Right rate Nutrient supplying capacity of soil by soil testing.
Nutrient supplying capacity of soil by plant uptake.
Nutrient requirement of crop by crop yield.
Use efficiency of applied nutrient.

11. IV II
III I

12. P and K requirements for cereals as predicted by QUEFTS
Crop
Reciprocal internal efficiency (kg nutrient/t grain) P K
Rice1
2.7
15.9
Maize2
2.56
17.4
Wheat3
4.0
20.0
1 Buresh et al. 2010
2 Setiyono et al. 2010
3 IPNI data (unpublished) 12

13. Right time
Assess dynamics of crop uptake, soil supply, and logistics of field operations.
Determine timing of nutrient loss risks.

14. Right time Basal application of P fertilizer.
Nitrogen at early stage of growth for tillering.
Nitrogen at PI stage for increasing number of spikelets per panicle.
Potassium at PI stage in light texture soils.

15. Right rate
Assess soil nutrient supply and plant demand.

16. Right source Ensure a balanced supply of essential nutrients, and
Consider both naturally available sources and characteristics of specific products, in plant-available forms.

17. Right source
Available organic fertilizer – cowdung and poultry manure instead of TSP/DAP.
Rice straw for K fertilizer.

18. Summary
Right place – application of TSP at root zone, deep placement or incorporation of N fertilizer.
Right time – basal, active tillering and PI stage.
Right rate – crop demand based.
Right source – economic and environmental safety.