Master NCERT Class 8 Science

Chapter 1 - Crop Production and Management

Agricultural Practices

➔ Crop: When plants of the same kind are cultivated at one place on a large scale.
➔ Kharif Crops: Crops sown in the rainy season (June to September). Example: Paddy, Maize, Soybean, Groundnut, Cotton.
➔ Rabi Crops: Crops grown in the winter season (October to March). Example: Wheat, Gram, Pea, Mustard.

Basic Practices of Crop Production

➔ Preparation of Soil: The first step. Involves turning and loosening the soil to allow roots to penetrate deep and breathe easily.
➔ Tilling / Ploughing: The process of loosening and turning the soil using a plough.
➔ Crumbs: Big pieces of soil that need to be broken down with a plank.

➔ Sowing: Planting healthy, good quality seeds into the soil. Often done using a Seed Drill to sow at equal distances and depths.
➔ Manure: An organic substance obtained from the decomposition of plant or animal waste. Enhances water holding capacity and soil texture.
➔ Fertilizers: Chemical substances rich in particular nutrients (e.g., Urea, NPK). Excessive use makes soil less fertile and causes water pollution.

Irrigation and Protection

➔ Irrigation: The supply of water to crops at regular intervals.
➔ Modern Methods: Sprinkler system (useful for uneven land) and Drip system (water falls drop by drop directly near the roots; best for saving water).
➔ Weeds: Undesirable plants that grow naturally along with the crop, competing for nutrients and water.
➔ Weedicides: Chemicals used to control and kill weeds (e.g., 2,4-D).

Harvesting & Storage

➔ Harvesting: The cutting of crop after it is mature. Usually takes 3-4 months for a cereal crop.
➔ Threshing: The process of separating the grain seeds from the chaff.
➔ Combine: A machine which is both a harvester and a thresher.
➔ Winnowing: Separation of grain and chaff by wind, used by farmers with small holdings.

➔ Storage: Grains must be dried in the sun to prevent moisture, insects, and fungi. Stored in silos or granaries.
➔ Animal Husbandry: Rearing animals on a large scale for food and other purposes.