Soil physical and chemical properties strongly influence soil health, nutrient availability, crop productivity and the sustainability of agricultural systems. This manual provides a concise and practical guide to commonly used methods of soil and plant analysis. The procedures are based on established scientific principles and adapted to the diverse soils, climates and agricultural practices of India. Emphasis is placed on methods that are reliable, economical and suitable for routine laboratory and field applications. Each method explains its principle, apparatus, reagents, procedure, calculations, interpretation and precautions. The manual is intended for students, researchers, laboratory personnel and scientists working in soil science, agronomy and environmental science.

This chapter introduces soil testing as an essential component of scientific nutrient and land management. It traces the establishment and expansion of soil-testing laboratories in India and explains their role in assessing soil fertility, productivity and physical, chemical and biological conditions. Soil testing helps determine suitable fertilizer and amendment requirements while preventing the excessive or unbalanced application of nutrients. The chapter emphasizes that fertilizer recommendations must reflect differences among soils and fields. It also introduces representative soil sampling as the foundation of dependable laboratory results and outlines important precautions concerning equipment calibration, clean glassware, contamination prevention and safe laboratory practices.

This chapter explains how representative soil samples should be collected, labelled, transported and prepared for analysis. It identifies essential sampling equipment, including spades, khurpis, augers, trays, sampling bags, markers and polythene sheets. The recommended procedure involves dividing land into uniform sampling units, collecting soil from several well-distributed locations and combining these portions into a composite sample. The chapter describes V-shaped sampling cuts, suitable sampling depths and sample reduction through quartering. It also lists the field information that should accompany each sample. Procedures for air-drying, grinding, sieving and mixing samples are presented, together with precautions for avoiding unusual areas and contamination.  

This chapter presents laboratory procedures for measuring the major physical properties that regulate soil behaviour, water availability, aeration and root development. It begins with particle-density determination using a pycnometer and proceeds to bulk density, soil texture, moisture content, total pore space, porosity and water-holding capacity. Each practical exercise provides the underlying principle, required apparatus, procedural steps, calculations and relevant precautions. The hydrometer method is introduced for estimating the proportions of sand, silt and clay. Methods for evaluating moisture retention and pore relationships are also described. Collectively, these measurements help characterize soil structure, compaction, drainage, water storage and its suitability for crop production.

This chapter describes methods for evaluating soil reaction, salinity, organic matter and plant-available nutrients. It begins with soil pH and electrical conductivity, explaining their importance in nutrient availability and the identification of acidic, saline or alkaline conditions. Procedures are then provided for estimating organic carbon, available nitrogen, phosphorus, potassium and sulphur. The chapter also covers calcium, magnesium and micronutrients, including zinc, iron, copper, manganese, boron and molybdenum. Every method identifies the necessary apparatus and reagents and explains extraction, colour development, instrumental measurement, calculation and interpretation. Particular attention is given to calibration, sample preparation, reagent quality, contamination control and laboratory safe

This chapter introduces plant analysis as a means of determining crop nutrient status and diagnosing nutritional deficiencies. It explains the selection of representative plant tissues at suitable stages of growth, followed by washing, drying, grinding, digestion and elemental estimation. Recommended tissues and sampling stages are provided for cereals, pulses, oilseeds, fibre crops, vegetables, ornamentals and fruit crops. Procedures are included for estimating nitrogen, phosphorus, potassium, sulphur, boron, zinc, iron, copper and manganese in plant samples. The chapter stresses that reliable interpretation depends on correct tissue selection, careful sampling and freedom from contamination. It thereby connects laboratory measurements with crop nutrition and fertilizer management.