NCERT Class 9 Science Solutions: Chapter 15 Improvement in Food Resources Part 2

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Question 1:

Q. Which of the following conditions will give the most benefits? Why?

(a) Farmers use high-quality seeds, do not adopt irrigation or use fertilizers.

(b) Farmer use quality seeds, adopt irrigation, use fertilizer and use crop protection measures.

(c) Farmers use quality seeds, adopt irrigation, use fertilizer and use crop protection measures.


(c)Farmers using good quality seeds, adopting irrigation, using fertilizers, and using crop protection measures will derive most benefits.

(i) The use of good quality seeds increases the total crop production. If a farmer is using good quality seeds, then a majority of the seeds will germinate properly, and will grow into a healthy plant.

(ii) Proper irrigation methods improve the water availability to crops.

(iii) Fertilizers ensure healthy growth and development in plants by providing the essential nutrients such as nitrogen, phosphorus, potassium, etc.

(iv) Crop protection measures include various methods to control weeds, pests, and infectious agents. If all these necessary measures are taken by a farmer, then the overall production of crops will increase.

Question 1:

Q. Why should preventive measure and biological control methods be preferred for protecting crops?


Preventive measures and biological control methods should be preferred for protecting crops because excessive use of chemicals leads to environmental problems. These chemicals are also poisonous for plants and animals. Preventive measures include proper soil and seed preparation, timely sowing of seeds, intercropping and mixed cropping, usage of resistant varieties of crops, etc. On the other hand, biological control methods include the usage of bio-pesticides is bacillus thuringiensis, which is an insect pathogen that kills a wide range of insect larvae. Therefore, both preventive measures and biological control methods are considered eco-friendly methods of crop protection.

Question 2:

Q. What factors may be responsible for losses of grains during storage?


During the storage of grains, various biotic factors such as insects, rodents, mites, fungi, bacteria, etc. and various abiotic factors such as inappropriate moisture, temperature act on stored grains and result in degradation, poor germ-inability, discoloration, etc.

Question 1:

Q. Which method is commonly used for improving cattle breeds and why?

Q 1 Image Showing Sahiwal Breed.

Q 1 Image Showing Sahiwal Breed

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Cattle farming is commonly used for improving cattle breeds. The purpose of cattle farming is to increase the production of milk and draught labour for agricultural work. Dairy animals (Females) are used for obtaining milk and draught, irrigation, tilling, etc. cross breeding between two good varieties of cattle will produce a new improved variety. For example, the cross between foreign breeds such as Jersey Brown, Swiss (having long lactation period) and Indian breeds such as Red Sindhi, Sahiwal (having excellent resistance power against diseases) Produces a new variety having qualities of both breeds.

Question 1:

Q. Discuss the implications of the following statement:

“It is interesting to note that poultry is India’s most efficient converter of low fibre food stuff (Which is unit for human consumption) into highly nutritious animal protein food.”


Poultry in India is the most efficient converter of low fibre food stuff into highly nutritious animal protein food. In poultry farming, domestic fowls are raised to produce eggs and chicken. For this, the fowls are given animal feeds in the form of roughage, which mainly consists of fibers. Thus by feeding animals a fibre rich diet, the poultry gives highly nutritious food in the form of eggs and chicken.

Question 1:

Q. What management practices are common in dairy and poultry farming?


Common management practices in dairy and poultry farming are:

(i) Proper shelter facilities and their regular cleaning.

(ii) Some basic hygienic conditions such as clean water, nutritious food, food, etc.

(iii) Animals are kept in spacious, airy, and ventilated place.

(iv) Prevention and curve of diseases at the right time is ensured.