Location via proxy:   [ UP ]  
[Report a bug]   [Manage cookies]                
SlideShare a Scribd company logo

Soil fertility evaluation and fertilizer recommendation

•Download as PPTX, PDF•
•
B
BharathM64

This document discusses different approaches for evaluating soil fertility and determining fertilizer recommendations, including soil analysis, plant analysis, and visual deficiency symptoms. It describes methods for both rapid tissue tests of fresh plant parts and total laboratory analysis of dried plant materials. Diagnosis and recommendations can be generalized, based on soil test ratings with adjustments, or use the soil test crop response and target yield concept to determine fertilizer doses needed to achieve specific yields.

1 of 20
Soil fertility evaluation and fertilizer recommendation
Soil Fertility Evaluation
 Soil Analysis  Plant Analysis  Biological methods  Visual symptoms of nutrient deficiency
Soil Analysis
Rating limits of soil test values Nutrient Low Medium High Organic carbon (%) Below 0.5 0.5 – 0.75 Above 0.75 Avail. N (kg ha-1) Below 280 280 – 560 Above 560 Avail. P (kg ha-1) Below 22 22-56 Above 56 Avail. K (kg ha-1) Below 141 141-336 Above 336 Avail. S (ppm) Deficient < 10 ppm Sufficient > 10 ppm
1.plant analysis is an indirect evaluation of soil 2.plant analyses are interpreted on the basis of critical value approach Two general types of plant analysis are in use. 1. The Rapid tissue test which is customarily made on fresh tissue in the field. 2. Total analysis performed in the laboratory with precise analytical techniques
Rapid tissue tests  Determination of nutrient elements in the plant sap of fresh tissue.  Plant Part to be Selected: ◦ In general the conductive tissue of the latest mature leaf is used for testing.
Time of Testing:  The most critical stage of growth for tissue testing is at the time of bloom or from bloom to early fruiting stage.  Nitrates are usually higher in the morning than in the afternoon if the supply is short.  Test for nitrates Diphenylamine  Phosphates Molybdate + Stannous oxalate  For potassium Sodium cobalti nitrate
Total Analysis:  Total analysis is performed on the whole plant / plant parts  plant material is dried, ground, ashed and used for estimation  Precise analytical techniques are used for measurement of the various elements
Diagnosis and Recommendation Integrated System  It considers nutrient concentration ratios rather than individual element  The approach measures the relative balance between nutrients  Large number of sites is selected at random  Each element in the plant is expressed in as many ways as possible  Ex: Nutrientratios N/P, N/K or products NxP, NxK etc  NPK requirement of the crop is diagnosed using DRIS chart
Soil fertility evaluation and fertilizer recommendation
Soil fertility evaluation and fertilizer recommendation
Approaches  Generalized/blanket Recommendations  Soil Test Rating and Fertilizer Adjustment  Soil test crop response and target yield concept  Site specific nutrient management
Generalized/blanket Recommendations  Uniform application of RDF of a crop.  RDF Ex.(N, P2O5, K2O Kg/ha)  Rice :- 100:50:50  Maize:- 150:75:40  Red gram:- 25:50:25  Cotton:- 150:75:75
NUTRIENT Soil Test Ratings Kg/ha LOW MEDIUM HIGH N <280 280-560 >560 P2O5 <22 22-56 >56 K2O <141 141-336 >336 S <10ppm 10-20ppm >20ppm
RDF (Kg/ha) ADDITION IN RDF AT LOW FERTILITY DEDUCTION IN RDF AT HIGH FERTILITY NITROGEN <50 NO CHANGES NO CHANGES 50-100 +12.5 -12.5 100-175 +25 -25 175-250 +37.5 -37.5 250-325 +50 -50 PHOSPHORUS <25 NO CHANGES NO CHANGES 25-75 +12.5 -12.5 75-125 +25 -25 POTASSIUM <25 NO CHANGES NO CHANGES 25-50 +12.5 -12.5
Soil test crop response and target yield concept NUTRIENT REQUIREMENT (Kg/q) = TOTAL UPTAKE OF NUTRIENT (Kg/ha) YIELD OF GRAIN (q/ha) %CS = TOTAL UPTAKE OF NUTRIENT IN CONTROL PLOTS (Kg/ha) X 100AVAILABLE SOIL TEST VALVES OF CONROL PLOTS( Kg/ha) %CF = TOTAL UPTAKE OF NUTRIENT IN TREATED PLOTS (Kg/ha) --(AVAILABLE SOIL TEST VALVES OF TREATED PLOTS( Kg/ha) X %CS) X 100 FERTILIZER DOSE APPLIED(Kg/ha)
Target Yield Equation  Using the Basic Data, Fertilizer Dose Required for specific yield target is calculated by F=(NR *T – CS/100*S)*100/CF F= Fertilizer required kg/ha NR= Nutrient requirement kg/q T= Targeted yield q/ha CS= % contribution of N/P/K from soil S= Soil test value CF= % contribution of N/P/K from fertilizer
Soil fertility evaluation and fertilizer recommendation
Soil fertility evaluation and fertilizer recommendation

More Related Content

Soil fertility evaluation and fertilizer recommendation

  • 3.  Soil Analysis  Plant Analysis  Biological methods  Visual symptoms of nutrient deficiency
  • 5. Rating limits of soil test values Nutrient Low Medium High Organic carbon (%) Below 0.5 0.5 – 0.75 Above 0.75 Avail. N (kg ha-1) Below 280 280 – 560 Above 560 Avail. P (kg ha-1) Below 22 22-56 Above 56 Avail. K (kg ha-1) Below 141 141-336 Above 336 Avail. S (ppm) Deficient < 10 ppm Sufficient > 10 ppm
  • 6. 1.plant analysis is an indirect evaluation of soil 2.plant analyses are interpreted on the basis of critical value approach Two general types of plant analysis are in use. 1. The Rapid tissue test which is customarily made on fresh tissue in the field. 2. Total analysis performed in the laboratory with precise analytical techniques
  • 7. Rapid tissue tests  Determination of nutrient elements in the plant sap of fresh tissue.  Plant Part to be Selected: ◦ In general the conductive tissue of the latest mature leaf is used for testing.
  • 8. Time of Testing:  The most critical stage of growth for tissue testing is at the time of bloom or from bloom to early fruiting stage.  Nitrates are usually higher in the morning than in the afternoon if the supply is short.  Test for nitrates Diphenylamine  Phosphates Molybdate + Stannous oxalate  For potassium Sodium cobalti nitrate
  • 9. Total Analysis:  Total analysis is performed on the whole plant / plant parts  plant material is dried, ground, ashed and used for estimation  Precise analytical techniques are used for measurement of the various elements
  • 10. Diagnosis and Recommendation Integrated System  It considers nutrient concentration ratios rather than individual element  The approach measures the relative balance between nutrients  Large number of sites is selected at random  Each element in the plant is expressed in as many ways as possible  Ex: Nutrientratios N/P, N/K or products NxP, NxK etc  NPK requirement of the crop is diagnosed using DRIS chart
  • 13. Approaches  Generalized/blanket Recommendations  Soil Test Rating and Fertilizer Adjustment  Soil test crop response and target yield concept  Site specific nutrient management
  • 14. Generalized/blanket Recommendations  Uniform application of RDF of a crop.  RDF Ex.(N, P2O5, K2O Kg/ha)  Rice :- 100:50:50  Maize:- 150:75:40  Red gram:- 25:50:25  Cotton:- 150:75:75
  • 15. NUTRIENT Soil Test Ratings Kg/ha LOW MEDIUM HIGH N <280 280-560 >560 P2O5 <22 22-56 >56 K2O <141 141-336 >336 S <10ppm 10-20ppm >20ppm
  • 16. RDF (Kg/ha) ADDITION IN RDF AT LOW FERTILITY DEDUCTION IN RDF AT HIGH FERTILITY NITROGEN <50 NO CHANGES NO CHANGES 50-100 +12.5 -12.5 100-175 +25 -25 175-250 +37.5 -37.5 250-325 +50 -50 PHOSPHORUS <25 NO CHANGES NO CHANGES 25-75 +12.5 -12.5 75-125 +25 -25 POTASSIUM <25 NO CHANGES NO CHANGES 25-50 +12.5 -12.5
  • 17. Soil test crop response and target yield concept NUTRIENT REQUIREMENT (Kg/q) = TOTAL UPTAKE OF NUTRIENT (Kg/ha) YIELD OF GRAIN (q/ha) %CS = TOTAL UPTAKE OF NUTRIENT IN CONTROL PLOTS (Kg/ha) X 100AVAILABLE SOIL TEST VALVES OF CONROL PLOTS( Kg/ha) %CF = TOTAL UPTAKE OF NUTRIENT IN TREATED PLOTS (Kg/ha) --(AVAILABLE SOIL TEST VALVES OF TREATED PLOTS( Kg/ha) X %CS) X 100 FERTILIZER DOSE APPLIED(Kg/ha)
  • 18. Target Yield Equation  Using the Basic Data, Fertilizer Dose Required for specific yield target is calculated by F=(NR *T – CS/100*S)*100/CF F= Fertilizer required kg/ha NR= Nutrient requirement kg/q T= Targeted yield q/ha CS= % contribution of N/P/K from soil S= Soil test value CF= % contribution of N/P/K from fertilizer