Chapter 15 Improvement in Food Resources
Intext Questions
Question 1: What do we get from cereals, pulses, fruits and vegetables?
Answer: Cereals are the source of carbohydrate and provide us with energy. Pulses are the source of proteins and are required for growth and development. Fruits and vegetables are the main sources of vitamins and minerals and are required to protect us from diseases etc.
Question 2: How do biotic and abiotic factors affect crop production?
Answer: Biotic factors like microbes, insects may spread diseases or damage crop. Abiotic factors like temperature, rain, wind etc. may destroy the crops that are grown.
Question 3: What are the desirable agronomic characteristics for crop improvement?
Answer: The desirable agronomic characteristics for crop improvement are
• Tallness
• Profuse branching
Dwarfness is desired in cereals so that less nutrients are consumed by these crops. Thus developing varieties of desired agronomic characters help give higher productivity.
Question 4: What are macro nutrients and why are they called macro-nutrients?
Answer: Macro-nutrients are the nutrients that are used by organism in more quantity. Some of the macro-nutrients are nitrogen, carbon, oxygen etc.
Question 5: How do plants get nutrients?
Answer: Plants also require nutrients for growth and development. Nutrients are supplied to plants by air, water and soil. There are sixteen nutrients which are essential for plants. Air supplies carbon and oxygen, hydrogen comes from water, and soil supplies the other thirteen nutrients to plants.
Question 6: Compare the use of manure and fertilisers in maintaining the soil fertility.
Answer:
• Manure contains large quantities of organic matter and also supplies small quantities of nutrients to the soil.
• Manure helps in enriching soil with nutrients and organic matter and increasing soil fertility.
• The bulk of organic matter in manure helps in improving the soil structure.
• Fertilisers are commercially produced plant nutrients.
• Fertilisers increase the rate of soil erosion.
• Use of fertilisers can deplenish the organic matter in soil and hence making the soil acidic or basic.
Question 7: 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) Farmers use ordinary seeds, adopt irrigation and use fertilizer.
c) Farmers use quality seeds, adopt irrigation, use fertilizer and use crop protection measures.
Answer: If the farmers use quality seeds, adopt irrigation, use fertilizer and use crop protection measures, it will the most benefits. This is because the use of quality seeds is not sufficient until good irrigation system, fertilisers and crop protection measures are used.
Question 8: Why should preventive measures and biological control methods be preferred for protecting crops?
Answer: Excessive use of chemicals leads to environmental problems, hence biological methods are preferred for protecting the crops from viruses, pathogens along with increasing production. As chemicals are harmful, bio-pesticides are used for protecting the crops.
Question 9: What factors may be responsible for losses of grains during storage?
Answer: Biotic and abiotic factors may be responsible for losses of grains during storage. These include insects, fungi, pests, flood, rain, moisture etc.
Question 10: Which method is commonly used for improving cattle breeds and why?
Answer: Cross-breeding is the best method which is used for improving cattle breeds. In this method, breeding between two good cattle breeds result in a new variety of offspring. While breeding, care is taken to have a good resultant with a high yielding having resistance to diseases. Example: Foreign breeds like Jersey are selected for long lactation period, while local breed like Red Sindhi show excellent resistance to diseases.
Question 11: 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 unfit for human consumption) into highly nutritious animal protein food.”
Answer: 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 chickens. For this the fowls are given animal feeds in the form of roughage, which mainly consists of fibres. Thus, by feeding animals a fibre rich diet, the poultry gives highly nutritious food in the form of eggs and chickens.
Question 12: What management practices are common in dairy and poultry farming?
Answer:
• Well-designed hygienic shelter for dairy and poultry farming
• Good quality of food and fodder
• Protection from various diseases/infection
• Sunlight feasible and air ventilated shelter.
Question 13: What are the differences between broilers and layers and in their management?
Answer:
• Broilers: The poultry bird raised for meat purpose is called broiler. The daily food requirements for broilers is protein rich with adequate fat. The level of vitamin A and K is kept high in poultry feeds.
• Layers: The egg-laying poultry bird is called layer. The housing, environmental and nutritional requirements of broilers vary from those of egg layers. Layers require proper lighting and space.
Question 14: How are fish obtained?
Answer: There are two ways of obtaining fish. One is from natural resources, which is called capture fishing. The other way is by fish farming, which is called culture fishery.
Question 15: What are the advantages of composite fish culture?
Answer:
• A combination of 5 or 6 fish species is used in a single fish pond as they don’t compete for food.
• All the food resources are utilised.
• Increases fish yield from the pond.
• Survival of fishes increases.
Question 16: What are the desirable characters of bee varieties suitable for honey production?
Answer:
• The variety of bees should yield a large amount of honey.
• The bees should stay for a longer period of time in bee hives.
• The bee should not sting much.
• The bees should be disease resistant.
Question 17: What is pasturage and how is it related to honey production?
Answer: Pasturage refers to the flowers available to bees for nectar and pollen collection. The kind of flowers will determine the taste of the honey so pasturage is the main reason for good quality of honey.
Exercise Questions
Question 1: Explain any one method of crop production which ensures high yield.
Answer: Hybridisation is one of the methods of crop production which ensures high yield. Hybridisation refers to crossing between genetically dissimilar plants. This crossing may be intervarietal (between different varieties), interspecific (between two different species of the same genus) or intergeneric (between different genera).
Question 2: Why are manure and fertilisers used in fields?
Answer: Plants need nutrients for their growth and development. Deficiency of these nutrients affects physiological processes in plants including reproduction, growth and susceptibility to diseases. To increase the yield, the soil can be enriched by supplying these nutrients in the form of manure and fertilisers.
Question 3: What are the advantages of intercropping and crop rotation?
Answer: Intercropping is growing of two or more crops simultaneously on the same field in a definite pattern. Advantages:
• Checks pests and decreases the chances of spoiling crops.
• Decreased chances of soil erosion.
• Reduced loss of crops with high yield.
• Less water requirement.
The growing of different crops on a piece of land is a pre-planned succession is known as crop rotation. Advantages:
• Farmers can grow 2-3 crops in a year.
• Pulses take nitrogen directly from atmosphere and hence require minimal amount of fertilisers.
• Best use of land with proper supply of nutrients.
Question 4: What is genetic manipulation? How is it useful in agricultural practices?
Answer: Genetic manipulation is a process in which the transfer of genes take place from one organism to other. A gene of a particular character is introduced inside the chromosome cells, resulting in transgenic plant. Example: BT Cotton is a genetically modified crop which carries bacterial genes that protect this plant from insects. They are used in plants like rice, brinjal, maize to get protection from insects.
Question 5: How do storage grain losses occur?
Answer: Storage grain loss occurs due to abiotic and biotic factors like flood, wind, humidity, temperature, insects, birds, microbes etc.
Question 6: How do good animal husbandry practices benefit farmers?
Answer: Good animal husbandry practices benefits the farmers in following way:
• Yields in good quality cattle
• Better quality of production
• Use in agriculture like tilling, irrigation etc.
Question 7: What are the benefits of cattle farming?
Answer: The benefits of cattle farming are
• Cattles are used for agricultural purposes
• Generation of good quality cattle
• Milking and meat purpose
Question 8: For increasing production, what is common in poultry, fisheries and bee-keeping?
Answer: For increasing production, cross-breeding techniques are adopted in poultry, fisheries and bee-keeping. In addition to this, proper maintenance of cattle is required for good production.
Question 9: How do you differentiate between capture fishing, mariculture and aquaculture?
Answer:
• Capture fishing: It is a technique in which fish are captured from various sources of natural resources like sea, river, lakes etc.
• Mariculture: Culturing of marine fish like prawns, oysters, etc. in marine water for commercial use.
• Aquaculture: Culturing of fish in both marine and freshwater.
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