Forest Focus Group

Introduction

Nitrogen is one of the most essential nutrients for plant growth, but plants cannot directly use atmospheric nitrogen (N₂). Nitrogen-fixing microorganisms, present in biofertilizers, convert this nitrogen into ammonia or related compounds that plants can take up. These biofertilizers offer an eco-friendly and cost-effective alternative to chemical fertilizers, improving crop productivity without harming soil ecosystems.

Key Microorganisms Used

1. Rhizobium

• Forms symbiotic relationships with legumes such as soybean, peas, chickpeas, and clover.

• Fixes nitrogen within root nodules.

2. Azotobacter

• Free-living bacteria suitable for non-leguminous crops like wheat, maize, cotton, and vegetables.

• Improves seed germination and root development.

3. Azospirillum

• Associates with grasses and cereals.

• Enhances root growth and nitrogen uptake.

4. Blue-Green Algae (Cyanobacteria)

• Used mostly in rice cultivation.

• Improves soil organic matter.

5. Azolla–Anabaena System

• A water fern and cyanobacteria symbiosis.

• Common in paddy fields, adding nitrogen naturally.

6. Frankia

• Forms symbiotic relationships with non-leguminous woody plants.