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Here are the short notes for Class 8 Science, Chapter 1: Crop Production and Management in English:
1. Crop
When plants of the same kind are grown and cultivated at one place on a large scale, it is called a crop.
* Kharif Crops: Sown in the rainy season (June to September). Examples: Paddy, maize, soybean, groundnut, and cotton.
* Rabi Crops: Sown in the winter season (October to March). Examples: Wheat, gram, pea, mustard, and linseed.
2. Basic Practices of Crop Production
Cultivation of crops involves several steps taken by farmers:
* Preparation of Soil: Tilling or ploughing the soil to make it loose, allowing roots to breathe and pe*****te deep.
* Sowing: Selecting clean, healthy, and high-yielding seeds and planting them at the right depth and distance.
* Adding Manure and Fertilizers: Adding substances to the soil to replenish nutrients.
* Manure: Organic substance obtained from decomposition of plant/animal wastes.
* Fertilizers: Chemical substances rich in specific nutrients (e.g., Urea, Potash).
* Irrigation: Supplying water to crops at regular intervals.
* Modern Methods: Sprinkler system and Drip system (saves water).
* Protection from Weeds: Removing undesirable plants (weeds) that grow naturally with the crop. This process is called Weeding.
* Harvesting: Cutting of crop after it is mature. Threshing is the process of separating grains from the chaff.
* Storage: Keeping harvested grains safe from moisture, insects, rats, and microorganisms in Silos or Granaries.
3. Difference Between Fertilizer and Manure
| Feature | Fertilizer | Manure |
|---|---|---|
| Nature | Man-made inorganic salt. | Natural substance from cattle dung and plant residues. |
| Preparation | Prepared in factories. | Can be prepared in the fields. |
| Humus | Does not provide any humus to soil. | Provides a lot of humus to the soil. |
| Nutrients | Very rich in Nitrogen, Phosphorus, and Potassium. | Relatively less rich in plant nutrients. |
4. Nitrogen Fixation
Bacteria called Rhizobium, present in the root nodules of leguminous plants (like pulses), fix atmospheric nitrogen into the soil to increase fertility.
Would you like me to explain any specific term like "Drip Irrigation" or "Tilling" in more detail?

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