NCERT Exemplar Class 9 Science Solutions Chapter 15 Improvement in Food Resources

NCERT Exemplar Class 9 Science Solutions Chapter 15

By practicing the solved exercise that includes MCQs, short and long answer provides a clear understanding of how to approach and answer questions in a skillful manner.

Get answers to Improvement in Food Resources NCERT Exemplar Class 9 Science Solutions Chapter 15-MCQ

Question:1

Which one is an oil yielding plant among the following?
(a) Lentil
(b) Sunflower
(c) Cauliflower
(d) Hibiscus
Answer: The correct answer is option(b), Sunflower.

Explanation: Sunflower is mainly cultivated for their seeds, which contain a high percentage of oil. The oil is commonly used for cooking as well as in cosmetics. Lentils are grown for their seeds, cauliflower is a vegetable, and hibiscus yields seeds.

Question:2

Which one is not a source of carbohydrate?
(a) Rice
(b) Millets
(c) Sorghum
(d) Gram
Answer: The correct answer is option(d), Gram

Explanation: Rice, millet, and sorghum are rich in carbohydrates, whereas gram is a primary source of protein and fiber.

Question:3

Find out the wrong statement from the following
(a) White revolution is meant for increase in milk production
(b) Blue revolution is meant for increase in fish production
(c) Increasing food production without compromising with environmental quality is called as sustainable agriculture
(d) None of the above
Answer: The correct answer is option(d), None of the above

Explanation: White revolution is launched to increase the production of milk in 1970 by Dr Verghese Kurien. In 1960, to increase the utilization of water and benefit of fishermen blue revolution was started. Sustainable agriculture is defined as increasing food production without compromising environmental quality.

Question:4

To solve the food problem of the country, which among the following is necessary?
(a) Increased production and storage of food grains
(b) Easy access of people to the food grain
(c) People should have money to purchase the grains
(d) All of the above
Answer: The correct answer is option (d), All of the above.

Question:5

Find out the correct sentence

1. Hybridization means crossing between genetically dissimilar plants

2. Cross between two varieties is called as inter specific hybridization

3. Introducing genes of desired character into a plant gives genetically modified crop

4. Cross between plants of two species is called as inter varietal hybridization

(a) (i) and (iii)
(b) (ii) and (iv)
(c) (ii) and (iii)
(d) (iii) and (iv)

Answer: The correct answer is option(a).

Explanation: For having good qualities of different plants, the process of crossing between genetically dissimilar plants is used and this process is called hybridization. In genetically modified crops, we tried to introduce genes of the desired character into any plant. There are multiple type of hybridization and they are developed for different needs.

• If this crossing is done between different varieties, it is called Intervarietal hybridization.

• If the crossing is done between different genes, then it is called inter- generic hybridization.

• If crossing is done between different species of same gene it is called inter-specific hybridization.

• In genetically modified crops we tried to introduce genes of the desired character into any plant.

Question:6

Weeds affect the crop plants by
(a) killing of plants in field before they grow
(b) dominating the plants to grow
(c) competing for various resources of crops (plants) causing low availability of nutrients
(d) all of the above
Answer: The correct answer is option(d), All of the above

Explanation: Weeds are unwanted plants that grow along with crops. These weeds start to use resources like space, water, light, and nutrients of the crops due to which availability of nutrients gets reduced and need to be killed in the field before they grow.

Question:7

Which one of the following species of honeybee is an Italian species?
(a) Apis dorsata
(b) Apis florae
(c) Apis cerana indica
(d) Apis mellifera
Answer: The correct answer is option(d), Apis mellifera

Explanation: Honeybee is a special kind of fly and its genus name is Apis. Apis florea is a small honeybee of south east Asia.
Apis dorsata is a large honeybee of south east Asia.
Apis cerena is an Indian domestic honeybee.
Apis melifera is the most common honeybee which is domesticated. It is also known as the Italian bee.

Question:8

Find out the correct sentence about manure
(i) Manure contains large quantities of organic matter and small quantities of nutrients.
(ii) It increases the water holding capacity of sandy soil.
(iii) It helps in draining out of excess of water from clayey soil.
(iv) Its excessive use pollutes environment because it is made of animal excretory waste.
(a) (i) and (iii)
(b) (i) and (ii)
(c) (ii) and (iii)
(d) (iii) and (iv)
Answer: The correct answer is option(b).

Explanation: Manure is also known as fertilizer, and it is used in agriculture. Manure increases the fertility of land by giving organic matter and nutrients to the soil. Manure also increases the humus level in soil, which increases the water holding capacity of soil.

Question:9

Cattle husbandry is done for the following purposes
(i) Milk Production
(ii) Agricultural work
(iii) Meat production
(iv) Egg production
(a) (i), (ii) and (iii)
(b) (ii), (iii) and (iv)
(c) (iii) and (iv)
(d) (i) and (iv)
Answer:The correct answer is option(a)

Explanation: Animal Husbandry related to cattle is done for the production of milk and meat and also doing the work of agriculture such as bull is used for ploughing the fields.

Question:10

Which of the following are Indian cattle?
(i) Bos indicus
(ii) Bos domestica
(iii) Bos bubalis
(iv) Bos vulgaris
(a) (i) and (iii)
(b) (i) and (ii)
(c) (ii) and (iii)
(d) (iii) and (iv)
Answer: The correct answer is option(a)

Explanation: Bos indicus are termed as Zebu, which are domestic cattle that originate from the Indian subcontinent, and Bos bubalis are generally termed as wild water buffalo and are found in parts of India and Southeast Asia.

Question:11

Which of the following are exotic breeds?
(i) Brawn
(ii) Jersey
(iii) Brown Swiss
(iv) Jersey Swiss
(a) (i) and (iii)
(b) (ii) and (iii)
(c) (i) and (iv)
(d) (ii) and (iv)
Answer:The correct answer is option(b).

Explanation: Brawn: It is also termed as Head cheese and is basically a meat jelly made by flesh coming from the head of a pig or calf.
Jersey: This breed of cow originated from of the Channel Islands of United Kingdom called Jersey. Brown Swiss: This cattle breed is also termed as American Brown Swiss and it originates from United States. Jersey Swiss: There is no breed or term as such.

Question:12

Poultry farming is undertaken to raise following
(i) Egg production
(ii) Feather production
(iii) Chicken meat
(iv) Milk production
(a) (i) and (iii)
(b) (i) and (ii)
(c) (ii) and (iii)
(d) (iii) and (iv)
Answer:The correct answer is option(a)

Explanation: Poultry farming is majorly used to produce eggs and Chicken meat. Poultry does not produce milk. Milk production is done by Cattle.

Question:13

Poultry fowl are susceptible to the following pathogens
(a) Viruses
(b) Bacteria
(c) Fungi
(d) All of the above
Answer: The correct answer is option (d)

Question:14

Which one of the following fishes is a surface feeder?
(a) Rohus
(b) Mrigals
(c) Common carps
(d) Catlas
Answer: The correct answer is option(d).

Explanation: Rohus: These fishes are generally large in size and are omnivores. They are column feeders, and their feeding takes place on food available in the mid column.
Mirgals: They come under the category of bottom feeders as the feed on vegetation(decayed) found at the bottom.
Common carps: These fishes are omnivores and feed on zooplankton, insects and crustaceans found at the bottom. They are bottom feeders.
Catlas: They are surface feeders and feed on zooplankton.

Question:15

Animal husbandry is the scientific management of
(i) animal breeding
(ii) culture of animals
(iii) animal livestock
(iv) rearing of animals
(a) (i), (ii) and (iii)
(b) (ii), (iii) and (iv)
(c) (i), (ii) and (iv)
(d) (i), (iii) and (iv)

Answer: The correct answer is option(d).

Explanation: Animal husbandry is the scientific management of animal breeding, animal livestock and rearing of animals.

Question:16

Which one of the following nutrients is not available in fertilizers?
(a) Nitrogen
(b) Phosphorus
(c) Iron
(d) Potassium
Answer: The correct answer is option (c), Iron

Explanation: Fertilizers are the chemical substances which provide nutrients to a plant, which leads to an increase in the growth and yield of a plant or crop. They provide Potassium, Nitrogen and Phosphorus to the plant.

Question:17

Preventive and control measures adopted for the storage of grains include
(a) strict cleaning
(b) proper disjoining
(c) fumigation
(d) all of the above
Answer: The correct answer is option(d), All of the above

Explanation: In order to prevent the grains from insects, mites the storage places should be managed by taking Preventive and control measures which include:
Strict cleaning: The produce is properly cleaned before it is moved for storage.
Proper disjoining: Different produce should be kept at separate levels from each other.
Fumigation: Chemicals are used in the storage spaces to kill the pests.

Unlock the Short Answers of NCERT Exemplar Class 9 Science Solutions Chapter 15

Question:18

Match the column A with the column B

Answer: (a)-(ii), (b)-(iii), (c)-(i), (d)-(iv)
Rohu: These fishes are generally large in size and are omnivores. They are column feeders, and their feeding takes place on food available in the mid column.
Mirgal: They come under the category of bottom feeders as the feed on vegetation(decayed) found at the bottom.
Catla: They are surface feeders and feed on zooplankton.
Fish farming is also termed as pisiculture which includes raising fishes for commercial purposes. A similar term for fish farming is Culture fishery where selected species of fishes are cultivated on a pond.

Question:19

Fill in the blanks
(a) Pigeon pea is a good source of______.
(b) Berseem is an important_______crop.
(c) The crops which are grown in rainy season are called_______crops.
(d) ______are rich in vitamins.
(e) ______crop grows in winter season.
Answer:

(a) Pigeon pea is a good source of Protein.

(b) Berseem is an important fodder crop.

(c) The crops that are grown in the rainy season are called rainy crops.

(d) Vegetables are rich in vitamins.

(e) Rabi crop grows in the winter season.

Question:20

What is a GM crop? Name any one such crop which is grown in India.
Answer: Genetically modified (GM) crops are plants that have been genetically changed by using biotechnology to increase desirable traits such as resistance to pests, tolerance to herbicides, or improved nutritional content.

An example of such a crop grown in India is Bt Cotton (Bacillus thuringiensis). It is the only approved GM crop in India.

Question:21

List out some useful traits in improved crop?
Answer:
The traits in an improved crop are mentioned below:

1. Higher Yield- Improved crops produce more grain, fruits, or vegetables per unit area.

2. Drought Resistance- These crops can tolerate water scarcity and survive in dry conditions.

3. Pest and Disease Resistance- Improved crops are resistant to specific pests and diseases, reducing the need for pesticides.

4. Improved Nutritional Quality- It enhances the nutritional value of crops by increasing vitamins, minerals, or other nutrients.

Question:22

Why is organic matter important for crop production?
Answer: Organic matter consists of animal and plant remains that have gone through decomposition. It is very important for crop production due to many reasons:

1- Organic matter increases the soil nutrients and makes the soil more porous.

2- Organic matter acts like a sponge that retains moisture in the soil and makes water available to plants during dry times.

3- Organic matter decomposes to release essential nutrients like nitrogen, phosphorus, etc., which are important for plant growth.

4- Organic matter helps bind soil particles together, which prevents soil and water erosion.

Question:23

Why is excess use of fertilizers detrimental for the environment?
Answer: The Detrimental Effects of Excessive Fertilizer use are given below:

1- Fertilizer reduces soil fertility over time by changing pH and decreasing organic matter.

2- Extra fertilizer flows away into rivers and lakes, making the water dirty and unsafe.

3- Fertilizers release harmful gases that contribute to global warming.

4- Excess fertilizer destroys tiny organisms in the soil that help plants to grow.

Question:24

Give one word for the following
(a) Farming without the use of chemicals as fertilizers, herbicides and pesticides is known as ———.
(b) Growing of wheat and groundnut on the same field is called as ———.
(c) Planting soyabean and maize in alternate rows in the same field is called as ———.
(d) Growing different crops on a piece of land in pre-planned succession is known as———.
(e) Xanthium and Parthenium are commonly known as———.
(f) Causal organism of any disease is called as ———.
Answer:

(a) Farming without the use of chemicals as fertilizers, herbicides, and pesticides is known as organic farming.

(b) Growing wheat and groundnut on the same field is called mixed cropping.

(c) Planting soybean and maize in alternate rows in the same field is called intercropping.

(d) Growing different crops on a piece of land in pre-planned succession is known as crop rotation.

(e) Xanthium and Parthenium are commonly known as weeds.

(f) A Causal organism of any disease is called as pathogen.

Question:25

Match the following A and B
(A) (B)
(a) Cattle used for tilling and carting (i) Milk producing female
(b) Indian breed of chicken (ii) Broiler
(c) Sahiwal, Red Sindhi (iii) Draught animals
(d) Milch (iv) Local breed of cattle
(e) Chicken better fed for obtaining (v) Aseel
meat
Answer:
(a)- (iii):
Draught animals are also termed as working animals which include domesticated ox and bull. These types of cattle are used for laborious tasks on the farm such as tilling and carting.
(b)-(v):
Aseel chicken is the breed which originates in Indian subcontinent.
(c)-(iv):
Sahiwal is of Zebu breed and originated in Sahiwal (Region of Punjab before the division of India and Pakistan). These are majorly used for dairy purposes.
Red Sindhi is also of Zebu breed and originated in Sindh region of Pakistan. They are amongst the most popular dairy breeds across India, Bangladesh and Pakistan.
(d)-(i):
Bos indicus(cows) which are milk-producing are termed as Milch.
(e)-(ii):
Chickens which are fed with the supplement feeds rich in vitamin to increase the growth rate and feed efficiency for the purpose of obtaining meat are termed as Broilers.

Question:26

If there is low rainfall in a village throughout the year, what measures will you suggest to the farmers for better cropping?
Answer: The following measures can be taken by the farmers.

• Farmers can grow drought-resistant crops that require less water.

• In case of low rainfall, crop rotation should be practiced to maintain soil fertility.

• Use drip irrigation or sprinklers to minimize water use.

• Farmers can harvest and store rainwater for use during dry periods.

• Farmers can use organic manure to improve the soil’s water-holding capacity.
  
  

Question:27

Group the following and tabulate them as energy-yielding, protein yielding, oil yielding and fodder crop.
Wheat, rice, berseem, maize, gram, oat, pigeon gram, sudan grass, lentil, soybean, groundnut, castor and mustard.
Answer :

Question:28

Define the term hybridization and photoperiod.
Answer: Hybridization: Hybridization is the process of crossing two different plants to produce a new plant with desirable characteristics, like better growth or pest resistance.

Photoperiod: Photoperiod is the amount of time a plant is exposed to light in a day, which affects its growth and flowering. The changes in photoperiod plays a significant role in a plant’s growth.

Question:29

Fill in the blanks
(a) Photoperiod affect the————.
(b) Kharif crops are cultivated from————to————.
(c) Rabi crops are cultivated from————to————.
(d) Paddy, maize, green gram and black gram are————crops.
(e) Wheat, gram, pea, mustard are————crops.
Answer :
a. Photoperiod affect the flowering process.
b. Kharif crops are cultivated from June to October.
c. Rabi crops are cultivated from November to April.
d. Paddy, maize, green gram and black gram are Kharif crops.
e. Wheat, gram, pea, mustard are Rabi crops.

Question:30

Cultivation practices and crop yield are related to environmental condition. Explain.
Answer: Crop yield depends on environmental conditions like temperature, rainfall, and sunlight. Proper water availability and soil quality also affect plant growth and the supply of nutrients. Pests and diseases spread more in certain climates, while extreme weather like droughts or floods can damage crops. The photoperiod influences flowering and fruiting and the timing of sowing and harvesting, which is important for better yield. The crop yield is affected by these environmental conditions as the growth of the crop and the duration of the cycle totally depend on these conditions.

Question:31

Fill in the blanks
(a) A total of———nutrients are essential to plants.
(b) ———and———are supplied by air to plants.
(c) ———is supplied by water to plants.
(d) Soil supply———nutrients to plants.
(e)———nutrients are required in large quantity and called as———.
(f) ——— nutrients are needed in small quantity for plants and are called ———.
Answer:
a) A total of sixteen nutrients are essential to plants.
b) Carbon and Oxygen are supplied by air to plants.
c) Hydrogen is supplied by water to plants.
d) Soil supply thirteen nutrients to plants.
e) Six nutrients are required in large quantity and called as Macronutrients.
f) Seven nutrients are needed in small quantity for plants and are called Micronutrients.

Question:32

Differentiate between compost and vermicompost?
Answer:

Question:33

Arrange these statements in correct sequence of preparation of green manure.
(a) Green plants are decomposed in soil.
(b) Green plants are cultivated for preparing manure or crop plant parts are used.
(c) Plants are ploughed and mixed into the soil.
(d) After decomposition it becomes green manure.
Answer:
(b) Green plants are cultivated for preparing manure or crop plant parts are used.
(c) Plants are ploughed and mixed into the soil.
(a) Green plants are decomposed in soil.
(d) After decomposition it becomes green manure.

Question:34

An Italian bee variety A. mellifera has been introduced in India for honey production. Write about its merits over other varieties.
Answer: There are several merits of this honey bee over other varieties, which are:

• Produces more honey compared to other bee species.

• Can be easily managed and reared in large numbers.

• Collects nectar from long distances, increasing honey production.

• Resistant to many local pests and diseases.

• Adaptable to different environmental conditions.

Question:35

In agricultural practices, higher input gives higher yield. Discuss how?
Answer: In farming, using better inputs usually gives more crops. Good seeds, fertilizers, water, and pesticides help plants grow well and give a higher yield. Fertilizers add nutrients to the soil, and enough water helps plants to grow properly. Pesticides protect crops from insects and diseases. Modern tools and machines also make farming easier and faster. When farmers use these inputs correctly, they get more and better crops.

Explore Long Answer of NCERT Exemplar Class 9 Science Solutions Chapter 15

Question:36

Discuss the role of hybridization in crop improvement.
Answer: Hybridization plays an important role in crop improvement, which is explained below:

• Hybrid plants often produce more crops than regular plants and give higher yields.

• Hybrids can resist diseases better, which can reduce crop loss.

• Hybrid crops may have improved taste, size, and shelf life.

• Hybrid plants can grow more quickly and mature earlier.

• They can be made to resist harmful insects to prevent any type of disease.

• Hybrids can grow very well in different climates and soils.

Question:37

Define
(i) Vermicompost
(ii) Green manure
(iii) Bio fertilizer
Answer:
1. Vermicompost: Vermicompost is a natural fertilizer made by breaking down organic waste with the help of earthworms. It is rich in nutrients and improves soil quality. Also, this process is faster than composting.

2. Green manure: Green manure is a type of organic fertilizer made by growing and ploughing back plants like legumes into the soil. It increases soil fertility and adds organic matter. Examples – Guar and sun hemp. Green manure helps in the enrichment of soil with phosphorus and nitrogen.

3. Biofertilizer: Biofertilizer is a substance containing living microorganisms that promote plant growth by providing essential nutrients like nitrogen and phosphorus. Azotobacter, Rhizobium, and Azospirilium supply nutrients to the crop/plant and are termed as Biofertilizers.

Question:38

Discuss various methods for weed control.
Answer: A weed is an unwanted plant that grows along with crops and competes for nutrients, water, sunlight, and space. Weeds reduce crop yield by taking away essential resources and can also cause diseases. They grow quickly and spread easily, making them difficult to control if not managed on time.
There are several methods by which we can control weeds:

• Weeds need to be removed by hand before they spread.

• Herbicides should be applied to kill weeds without harming the crop.

• Crop rotation can be practiced to prevent the growth of specific weeds.

• Mulch the soil to block sunlight and stop weed growth.

• Proper spacing should be there between plants to reduce weed competition.

• Grow cover crops that prevent weeds from taking root.

Question:39

Differentiate between the following
(i) Capture fishery and Culture fishery
(ii) Mixed cropping and Inter cropping
(iii) Bee keeping and Poultry farming
Answer :
(i)

(ii)

(iii)

Question:40

Give the merits and demerits of fish culture?
Answer: Fish culture is the process of raising fish in controlled environments like ponds or tanks to produce fish for food and other purposes.

Merits of Fish Culture:

• Fish culture provides a continuous supply of fish.

• It increases income and employment opportunities.

• This also reduces the pressure on natural water bodies.

• Fish culture allows control over fish growth, feeding, and health.

• It utilizes small water bodies effectively.

Demerits of Fish Culture:

• It requires high initial investment.

• This needs to be regularly monitored and managed.

• Fish culture increases the risk of water pollution if waste is not managed.

• High risk of diseases that can spread quickly.

Question:41

What do you understand by composite fish culture?
Answer: Composite fish culture is a system where different species of fish are raised and reproduce together in the same pond. These fishes are selected in such a way that they do not struggle and not fight over food, as they feed on different types of food available in the pond. This method increases fish production by using the complete pond efficiently.

Examples: Commonly used fish in composite fish culture include catla, rohu, and mrigal, which feed at different levels of the water body.

Question:42

Why bee keeping should be done in good pasturage?
Answer: Beekeeping should be done in good pastures because good pastures have plenty of flowers that provide nectar and pollen, which are very important for honeybees. When bees get enough food, they produce more honey and stay healthy. Good pastures also help bees collect nectar from a variety of flowers, thus improving the quality and quantity of honey. Additionally, healthy bees are at low risk of diseases, thus increasing the yield of honey.

Question:43

Write the modes by which insects affect the crop yield.
Answer: There are several modes by which insects affect the crop yield.

• Insects like caterpillars feed on leaves and stems, reducing the plant's ability to grow.

• Insects like aphids suck sap from plants, weakening them and reducing yield.

• Some insects bore into fruits and seeds, making them unfit for use.

• Insects can spread harmful plant diseases, affecting the entire crop.

• Insects like grubs attack roots, preventing the plant from absorbing water and nutrients.

• Insects attack can damage flowers, reducing fruit and seed production.

Question:44

Discuss why pesticides are used in very accurate concentration and in very appropriate manner?
Answer: Pesticides are used in accurate concentrations and in the right way to protect crops without causing harm. If too much pesticide is used, it leads to reduction of the organic matter, pollute the soil and water, and harm beneficial insects and animals. On the other hand, using less of pesticides may not control pests effectively, leading to crop damage. Accurate use ensures that pests are controlled while keeping the environment, animals, and humans safe.

Question:45

Name two types of animal feed and write their functions.
Answer: Two types of animal feed an their functions are given below:

1- Roughage: Roughage is a type of animal feed that is rich in fiber and low in energy. It includes green fodder like grass, hay and straw.

Roughage is important for proper digestion in animals, mainly in cows, buffaloes, and goats. It helps in maintaining a healthy digestive system by allowing the movement of food in the stomach.

2- Concentrates: It Includes grains, oil seeds, and their by-products.

Concentrates are important as it supplies energy and proteins for growth and milk production.

Question:46

What would happen if poultry birds are larger in size and have no summer adaptation capacity? In order to get small sized poultry birds, having summer adaptability, what method will be employed?
Answer: If poultry birds are larger in size and cannot adapt to hot weather, they may suffer from heat stress, grow slowly, and produce less eggs and requires a large amount of food. To get smaller, heat-tolerant birds, cross breeding is used. In this method, birds with desirable traits, such as smaller size and the ability to tolerate heat, are chosen and are raised over various generations. This help in developing a new breed of poultry that have better qualities to survive and perform well in hot climates.

Question:47

Suggest some preventive measures for the diseases of poultry birds.
Answer: Poultry birds are at high risk of getting diseases caused by several microbes. In order to prevent these diseases several measures need to be taken which are :-

1. Maintain Cleanliness: The poultry farm needs to clean and try to prevent the growth of harmful bacteria and viruses.

2. Vaccination: Birds of poultry farm needs to be vaccinated time to time to prevent any diseases affecting them.

3. Avoid overcrowding:The poultry farms need to be spacious and have to avoid overcrowding to reduce struggle and prevent diseases.

4. Quality food: Birds of poultry farms need to be feed with high quality food which boosts their immunity and promotes good health.

Question:48

Figure15.1 shows the two crop fields [Plots A and B] have been treated by manures and chemical fertilizers respectively, keeping other environmental factors same. Observe the graph and answer the following questions.
(i) Why does plot B show sudden increase and then gradual decrease in yield?
(ii) Why is the highest peak in plot A graph slightly delayed?
(iii) What is the reason for the different pattern of the two graphs?

Answer:

1. Plot B shows a sudden increase in the yield percentage of crop because when chemical fertilizers are used on the crop, they increase the yield of the crop immediately; but this increase in yield is temporary as the chemical fertilizers reduces the organic matters present in the soil and it also ends up killing the beneficial micro-organisms.
2. Plot A shows a delayed peak because when the plot is treated by manures, the small amount of nutrients is released into the soil at a very slow rate. The manure being rich source of organic matter leads to an increase the fertility of the soil.
3. The different pattern of the two graphs is observed because of the two separate methods used to increase the yield of crop in the plots. Manure being the organic way carried out the transfer of nutrients into the soil at a slow rate, providing the nutrients to the soil. Whereas the chemical fertilizers enhanced the soil fertility for a temporary period of time. The continuous use of chemical fertilizers on Plot B led to killing of micro-organisms required for soil. This affected the soil fertility and reduced the yield percentage.

Question:49

Complete the crossword puzzle (Fig.15.2)

Across
1. Oil yielding plant (9)
3. Crop grown in winter season (4)
5. Fixed by Rhizobium (8)
9. Common honey bee (4)
Downward
2. Animal feed (6)
4. A micronutrient (5)
6. Unwanted plant in crop fields (4)
7. An exotic breed of chicken(7)
8. Bottom feeders in fish pond(7)
10. A marine fish (4)
Answer:
Across
1. Oil yielding plant (9) - Sunflower
3. Crop grown in winter season (4) - Rabi
5. Fixed by Rhizobium (8) - Nitrogen
9. Common honey bee (4) - Apis
Downward
2. Animal feed (6) - Fodder
4. A micronutrient (5) - Boron
6. Unwanted plant in crop fields (4) - Weed
7. An exotic breed of chicken (7) - Leghorn
8. Bottom feeders in fish pond (7) - Mrigals
10. A marine fish (4) - Tuna