Unit 2225: Plant Nutrition

1. Introduction to Plant Nutrition

• Definition and importance of plant nutrition
• Essential nutrients: overview and classification
  • Macronutrients
  • Micronutrients and trace elements
• Role of nutrients in plant growth and development

2. Macronutrients for Plants

• Overview of macronutrients: Nitrogen (N), Phosphorus (P), Potassium (K)
• Nitrogen
  • Role in plant metabolism (e.g., amino acids, proteins, chlorophyll)
  • Sources and availability
• Phosphorus
  • Role in energy transfer (ATP), root development, flowering
  • Sources and availability
• Potassium
  • Role in osmoregulation, enzyme activation, disease resistance
  • Sources and availability

3. Micronutrients and Trace Elements

• Definition and importance of micronutrients
• Key micronutrients: Iron (Fe), Zinc (Zn), Manganese (Mn), Copper (Cu), Boron (B), Molybdenum (Mo), Chlorine (Cl), Nickel (Ni)
• Functions of primary micronutrients
  • Iron: chlorophyll synthesis and respiration
  • Zinc: enzyme function and growth regulation
  • Manganese: photosynthesis and nitrogen metabolism
• Sources and deficiency symptoms

4. Soil pH and Nutrient Availability

• Definition and measurement of soil pH
• Effect of pH on nutrient solubility and availability
  • Acidic soils vs alkaline soils
• Optimal pH range for nutrient uptake
• Impact of pH on plant growth
• Methods to amend soil pH (liming, sulfur application)

5. Absorption and Transport of Nutrients

• Root structure and nutrient uptake mechanisms
  • Passive absorption
  • Active transport
• Role of root hairs and mycorrhizae
• Translocation of nutrients via xylem and phloem
• Nutrient mobility within plants

6. Nutrient Deficiencies and Toxicities

• Common nutrient deficiency symptoms
  • Nitrogen deficiency: chlorosis, stunted growth
  • Phosphorus deficiency: dark green or purplish leaves
  • Potassium deficiency: leaf edge scorching
  • Micronutrient deficiencies: specific symptoms
• Nutrient toxicities and their causes
• Diagnostic techniques (visual, soil tests, tissue analysis)
• Treatment and prevention strategies

7. Fertilizers and Nutrient Management

• Types of fertilizers
  • Organic fertilizers (manure, compost)
  • Inorganic/synthetic fertilizers
• Fertilizer composition and labeling (N-P-K ratios)
• Application methods and timing
• Nutrient use efficiency
• Risks of over-fertilization

8. Sustainable Plant Nutrition Practices

• Principles of sustainable nutrient management
• Organic fertilization and soil health
• Crop rotation and intercropping for nutrient balance
• Use of biofertilizers and microbial inoculants
• Minimizing environmental impact and pollution
• Integrated nutrient management (INM) approaches