Overview
This lecture covers the key steps in crop production and management, types of crops, and important practices like soil preparation, sowing, irrigation, manuring, weeding, harvesting, and storage, as outlined in class 8 science.
Types of Crops
- Crops are plants cultivated in large quantities for food or other uses.
- Two main types: Kharif (rainy season, June-Sept) and Rabi (winter season, Oct-March) crops.
- Kharif crop examples: paddy (rice), maize, soya bean, groundnut, cotton.
- Rabi crop examples: wheat, gram, pea.
Steps in Crop Production
- Main steps: soil preparation, sowing, adding manures/fertilizers, irrigation, weeding, harvesting, storage.
- Preparation of soil involves loosening (tilling/ploughing) and leveling for better root growth and nutrient absorption.
- Ploughs, hoes, and cultivators are tools used for tilling; cultivators save time and labor.
- Sowing can be done by traditional (manual and animal-driven) or modern (seed drill) methods; seed drill ensures even sowing and seed protection.
Manures and Fertilizers
- Manures are natural substances from decomposed plant/animal waste, improve soil structure and add humus.
- Fertilizers are chemicals manufactured in factories, rich in specific nutrients (e.g., NPK: nitrogen, phosphorus, potassium).
- Excess fertilizer use can reduce soil fertility and cause water pollution.
- Crop rotation helps maintain soil fertility by alternating crops.
Irrigation
- Irrigation is supplying water to crops for growth, especially important for nutrient transport and seed germination.
- Traditional methods: moat, chain pump, dhekli, rahat; labor-intensive and less efficient.
- Modern methods: sprinkler system (sprays water over crops), drip irrigation (saves water, delivers directly to roots; best for dry regions).
Weeding and Crop Protection
- Weeds are unwanted plants growing with crops, competing for resources.
- Weeding is removal of weeds, done manually or using chemicals called weedicides.
- Weedicides are sprayed to selectively kill weeds without harming crops.
Harvesting and Storage
- Harvesting is cutting and collecting mature crops, done manually (sickle) or by machines (harvesters, combines).
- Threshing separates grain from chaff (combine performs both harvesting and threshing).
- Grains must be stored in dry, pest-proof conditions (silos, granaries, gunny bags, neem leaves) to prevent spoilage.
Animal Husbandry
- Animal husbandry is rearing animals on a large scale for products like milk, meat, and eggs.
Key Terms & Definitions
- Crop — Same plant species grown on a large scale in a field.
- Kharif Crop — Grown in rainy season (June-Sept), e.g., rice.
- Rabi Crop — Grown in winter (Oct-March), e.g., wheat.
- Tilling/Ploughing — Loosening and turning the soil for sowing.
- Seed Drill — Machine for sowing seeds evenly.
- Manure — Natural organic fertilizer from decomposed waste.
- Fertilizer — Artificial nutrient-rich chemical for crops.
- Irrigation — Supplying water to crops.
- Weeding — Removing unwanted plants from fields.
- Weedicides — Chemicals that kill weeds.
- Harvesting — Cutting and gathering mature crops.
- Threshing — Separating grain from chaff.
- Animal Husbandry — Rearing animals for food products.
Action Items / Next Steps
- Review the differences between Kharif and Rabi crops.
- Study the steps of crop production and match each to its tools/methods.
- Prepare for questions about advantages/disadvantages of manures vs. fertilizers.
- Read more about irrigation methods and their importance.
- Complete assigned NCRT questions for this chapter.