Agronomy Module 6

Cropping Systems

1. Rice-wheat system is predominant in Indo-Gangetic Plains.
2. Maize-legume intercropping improves nitrogen availability and yield.
3. Relay cropping ensures continuous production and risk reduction.
4. Mixed cropping increases crop diversity and reduces pest incidence.
5. Strip cropping reduces soil erosion and runoff.
6. Contour farming minimizes soil erosion on slopes.
7. Alley cropping combines trees and crops for sustainable farming.
8. Crop rotation breaks the life cycle of pests and diseases.
9. Zero tillage conserves soil moisture and reduces labor.
10. Raised bed planting improves drainage and root aeration.

Sustainable & Resource-Conserving Practices

1. Green manuring improves soil fertility and organic carbon content.
2. Cover crops reduce nutrient leaching and soil erosion.
3. Organic farming avoids synthetic fertilizers and pesticides.
4. Integrated nutrient management combines organic and chemical fertilizers.
5. Conservation agriculture reduces soil erosion and improves water-use efficiency.
6. Crop residue management maintains soil organic matter and fertility.
7. Mulching conserves soil moisture and regulates temperature.
8. Biofertilizers reduce dependence on chemical fertilizers.
9. Integrated pest management minimizes pesticide use and environmental impact.
10. Water harvesting and micro-irrigation improve water availability in dry areas.

Weeds and Their Management

1. Weeds reduce crop yield by 10–50% if unmanaged.
2. Echinochloa crus-galli is a major weed in rice fields.
3. Parthenium hysterophorus is a highly invasive weed.
4. Pre-emergence herbicides act before weed emergence.
5. Post-emergence herbicides act after weed emergence.
6. Mulching suppresses weed growth naturally.
7. Manual weeding is eco-friendly but labor-intensive.
8. Allelopathic crops like sorghum suppress weed growth.
9. Integrated weed management combines mechanical, cultural, and chemical control.
10. Correct herbicide doses avoid crop injury.

Soil and Fertility Management

1. Sandy soils have low water and nutrient retention.
2. Clay soils retain nutrients but may have poor drainage.
3. Loam soils are ideal for most crops.
4. Acid soils are corrected by liming.
5. Saline soils are reclaimed by leaching with good quality water.
6. Organic manures improve soil texture, fertility, and microbial activity.
7. Green manure crops include Sesbania, Sunhemp, Dhaincha.
8. Proper NPK application improves growth and yield.
9. Micronutrients like Zn, B, Fe are essential for crop growth and quality.
10. Split application of nitrogen reduces leaching and increases efficiency.

Irrigation and Water Management

1. Critical irrigation stages include flowering, fruiting, and grain filling.
2. Drip irrigation delivers water directly to roots.
3. Sprinkler irrigation mimics rainfall.
4. Flood irrigation is inefficient but common in rice.
5. Mulching conserves moisture and moderates soil temperature.
6. Waterlogging reduces oxygen availability and crop growth.
7. Deficit irrigation saves water in drought-tolerant crops.
8. Basin irrigation is used in fruit orchards.
9. Furrow irrigation suits row crops like maize and sugarcane.
10. Efficient water management improves yield stability.

Miscellaneous Important Facts

1. Photosynthesis occurs in green leaves.
2. Respiration provides energy for growth.
3. Transpiration regulates plant temperature and nutrient transport.
4. Harvest index = Economic yield ÷ Biological yield.
5. Seed treatment reduces seed-borne diseases.
6. Hybrid seeds give higher yield due to heterosis.
7. Plant spacing affects light interception, nutrient uptake, and yield.
8. Proper harvesting ensures quality and market value.
9. Crop residues improve soil fertility and organic carbon.
10. Integrated crop management improves productivity, sustainability, and profit.