NCERT Solutions Class 8 Science Chapter 1 – Crop Production and Management
NCERT Solutions for Class 8 Science Chapter 1: Crop Production and Management
This chapter introduces agricultural practices, types of crops, and modern farming techniques. Understanding these concepts helps students appreciate food production and agricultural science.
Exercise Questions and Answers
Q1. Select the correct word from the following list and fill in the blanks:
float, water, crop, nutrients, preparation
(a) The same kind of plants grown and cultivated on a large scale at a place is called _______.
(b) The first step before growing crops is _______ of the soil.
(c) Damaged seeds would _______ on top of water.
(d) For growing a crop, sufficient sunlight and _______ and _______ from the soil are essential.
Answer:
- (a) crop
- (b) preparation
- (c) float
- (d) water and nutrients
Q2. Match items in Column A with those in Column B:
| Column A | Column B |
|---|---|
| (i) Kharif crops | (c) Paddy and maize |
| (ii) Rabi crops | (d) Wheat, gram, pea |
| (iii) Chemical fertilizers | (a) Urea and superphosphate |
| (iv) Organic manure | (b) Animal excreta, cow dung |
Q3. Give two examples of each: (a) Kharif crop (b) Rabi crop
Answer:
- (a) Kharif crops: Paddy (rice), Maize, Soybean, Groundnut, Cotton
- (b) Rabi crops: Wheat, Gram (chana), Peas, Mustard, Linseed
Q4. Write a paragraph in your own words on each of the following: (a) Preparation of soil (b) Sowing (c) Weeding (d) Threshing
Answer:
(a) Preparation of soil: Soil preparation is the first step in farming. It involves loosening and turning the soil using tools like plough, hoe, or cultivator. This process is called tilling or ploughing. Loose soil allows roots to penetrate deeper, improves air circulation, and helps in mixing nutrients. It also brings nutrient-rich soil to the top and buries weeds.
(b) Sowing: Sowing is the process of putting seeds in the soil. Good quality seeds are selected by soaking them in water – damaged seeds float while healthy seeds sink. Seeds are sown at proper depth and distance using traditional tools (funnel-shaped tool) or modern seed drills. Proper spacing ensures adequate sunlight, nutrients, and water for each plant.
(c) Weeding: Weeding is the removal of unwanted plants (weeds) that grow along with crops. Weeds compete with crops for water, nutrients, sunlight, and space. They can be removed manually by hand or using a khurpi, or by using weedicides (chemicals that kill weeds). Weeding should be done before weeds produce flowers and seeds.
(d) Threshing: Threshing is the process of separating grain seeds from the harvested crop (chaff). It can be done manually by beating the dried crop or using machines called threshers. For small quantities, winnowing (using wind to separate lighter chaff from heavier grains) is used.
Q5. Explain how fertilizers are different from manure.
| Fertilizers | Manure |
|---|---|
| Chemical substances | Natural organic substances |
| Prepared in factories | Prepared in fields from decomposition |
| Rich in specific nutrients (N, P, K) | Contains all nutrients but in smaller amounts |
| Does not add humus to soil | Adds humus to soil |
| Expensive | Less expensive/free |
| Examples: Urea, NPK | Examples: Compost, vermicompost |
Key Takeaways
- Crops are plants of the same kind grown on a large scale
- Kharif crops (monsoon) vs Rabi crops (winter) have different growing seasons
- Agricultural practices: soil preparation → sowing → irrigation → weeding → harvesting → storage
- Manure is organic and improves soil structure; fertilizers provide specific nutrients
- Proper storage protects grains from pests and moisture
Leave a Reply