fertilizer management m a saleque. soil fertilization or crop fertilization same different
TRANSCRIPT
Fertilizer Management
M A Saleque
Soil fertilization or crop fertilization
• Same
• Different
4 R
• Right source
• Right Rate
• Right time
• Right place
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.
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.
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.
I
II III IV
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1 Buresh et al. 20102 Setiyono et al. 20103 IPNI data (unpublished)
Right time
• Assess dynamics of crop uptake, soil supply, and logistics of field operations.
• Determine timing of nutrient loss risks.
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.
Right rate
• Assess soil nutrient supply and plant demand.
Right source
• Ensure a balanced supply of essential nutrients, and
• Consider both naturally available sources and characteristics of specific products, in plant-available forms.
Right source
• Available organic fertilizer – cowdung and poultry manure instead of TSP/DAP.
• Rice straw for K fertilizer.
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.