SSAC-122

SSAC-122: SOIL CHEMISTRY, SOIL FERTILITY AND NUTRIENT MANAGEMENT

Credits: 3(2+1)

THEORY:
Soil as a source of plant nutrients, Essential and beneficial elements, criteria of essentially, forms of nutrients in soil, mechanisms of nutrients transport to plants, factors affecting nutrient availability to plants, Measures to overcome deficiencies and toxicities. Problem soils – Acid, Salt Affected and Calcareous Soils, characteristics, nutrient availabilities. Reclamation – Mechanical, Chemical and Biological Methods. Fertilizer and insecticides and their effect on soil water and air. Irrigation water – quality of irrigation water and its appraisal. Indian Standards for water quality. Chemistry of submerged and saline soil. Use of saline water for agriculture. Soil fertility – Different approaches for soil fertility evaluation methods, Soil testing – chemical methods. Critical levels of different nutrients in soil. Plant analysis – DRIS methods, critical levels in plants. Rapid Tissue Tests. Indicator Plants. Biological methods of soil fertility evaluation. Soil test based fertilizer recommendations to crops. Factors influencing Nutrients Use Efficiency (NUE) in respect of N, P, K, S, Fe and Zn fertilizers. Soil Health Card, Source, method and scheduling of nutrients for different soils and crops grown under rainfed and irrigated conditions.

PRACTICAL :
Principles of analytical instruments and their calibrations and applications, Colorimetry and Flame photometry. Estimation of available N, P, K, S and Zn in soils, pH, EC, Soluble Cations and Anions in soil water extracts. Lime requirement and Gypsum requirement of problem soils. Estimation of N, P and K in plant.

Practical (Experiments):
1) Principle and application of Spectro-photometry / Colorimetry.
2) Principle and application of Flame Photometry/Atomic Absorption Spectrophotometer (AAS).
3) Principle and application of 4. Determination of pH and EC from Soil Saturation Extract.
4) Determination of CaCO3 in soil (Rapid Titration Method).
5) Estimation of available N in soil (Subbiah and Asija, 1956).
6) Estimation of available P2O5 in soil. (Olsen et. al., 1954/ Bray’s)
7) Determination of available K2O in soil using Flame Photometer.
8) Estimation of Available Sulphur in soil (Turbidity Method).
9) Estimation of DTPA extractable Micronutrients from soil using AAS.
10) Determination of Exchangeable Ca and Mg in soil.
11) Determination of Carbonates and Bicarbonates in Soil Water Saturation Extract.
12) Lime/Gypsum requirement of problem soils.
13) Estimation of total N from plant sample by Micro Kjeldhals Method.
14) Estimation of Total P from plant sample by Vando Molybdate Method.
15) Estimation of Total K from plant sample using Flame Photometer.
16) Determination of Fe, Zn, Mn and Cu from plant sample by AAS.
17) Preparation and understanding of Soil Health Card.
18) Visit to Soil Testing Laboratory.