POINTS   TO   REMEMBER

We already know that:

  • All living organisms require food.
  • The energy from food is utilized by an organism for carrying out its various life processes such as digestion, respiration and excretion.
  • Plants can make their food themselves but animals including humans cannot.
  • We get food from plants or animals, or both.

 2. Crop: When plants of the same kind are grown at a place in a regular manner on a large scale, it is called a crop.

3. In our country three categories of crops are grown:
  • Kharif Crops:The crops which are sown in the rainy season (i.e., from June to September) are called kharif crops. Paddy, maize, soyabean, groundnut, cotton etc., are kharif crops.
  • Rabi Crops:The crops grown in winter season (i.e., from October to March) are called rabi crops. Examples of rabi crops are wheat, gram, pea, mustard, linseed.
  • Zayed Crops (or Summer Crops):The crops grown in summer season are called zayed crops. Moong, muskmelon, watermelon, cucumber, gourd and bitter gourd are examples of zayed crops.
4. Cultivation of crops involved following activities:

  • Soil Preparation:It involves loosening and tilling of the soil (i.e., ploughing and watering).
  • Sowing:Sowing is the process of putting seeds in the soil
  • Adding Manure and Fertilisers:The substances, which are added to the soil in the form of nutrients to improve the production of the crops and the fertility of the soil are called manure and fertilisers.
  • Irrigation:Supply of water to crops at appropriate intervals is called irrigation.
  • Protection from Weeds:Needs are the unwanted plants that grows along with the crops. Its removals is must for the better growth of the crops.
  • Harvesting:The cutting of crop after it is mature is called harvesting.
  • Storage:If the crop grains are to be kept for longer time, they should be safe from moisture, insects and rats

 5. Agricultural Practices:There are various activities that have to be performed, before sowing the seed and upto harvesting. These are called agricultural practice.

6. Fertilisers and Manure:
The substance which are added to the soil in the form of nutrients for the improvement of crop production and the fertility of the soil are called fertilisers and manure.

7. Thrashing:
The process of separation of grain from the chaff in the harvested plant is called thrashing.

8. Weeds:
There are other undesirable or unwanted plants may grow naturally along with the crop, such plants are called weeds.

9. Weedicides:
Those certain chemicals which are used to control weeds are called weedicide. For example: 2-4D (2-4-dichlorophenoxyacetic acid), metachlor.

10. Winnowing:
A process, which do the separation of grain and chaff is called winnowing.

11. Humus:
Humus is the top layer of the soil, i.e., formed by decaying or decomposition of organic matter like leaves or animal remains, dead organism, shed leaves or organism by the microorganism.

12. Pests:
Pests are the insects or rodents that destroy much of our crop yield. Thus, it is necessary to save crops from pests.

13. Important agricultural tools:

This is used for tilling the soil, adding fertilisers to the crop, removing the weeds, scraping of soil, etc. This implement is made of wood and drawn by a pair of bulls. (fig. 1.1)
It is used for removing weeds and for loosening the soil. (Fig. 1.2.)
Used for ploughing. It is driven by tractor use of cultivator saves labour and time. (Fig. 1.3.)
Traditional Tool:
The tool used traditionally for sowing seeds is shaped like a funnel. (Fig. 1.4)
Seed Drill:
Used for sowing with the help of tractors. This tool sows the seeds uniformly at a proper distance and depth. (Fig. 1.5.)
Used for manual harvesting. (Fig. 1.6.) 

                                                              Fig. 1.1 The plough
                                      Fig. 1.2. A hoe

                 Fig. 1.3. Cultivator driven by a tractor          Fig. 1.4. Traditional method of sowing

                Fig. 1.5.A seed drill                                                                                          Fig. 1.6. Sickle
                                            Fig. 1.7. A farmerSpraying weedicide
14. Food from Animals:
Like plants the animals also provide us with different kinds of food. Many people living in the coastal areas consume fish as a major part of their diet.

15. Animal Husbandry:
Animals reared at home or in a farm, have to be provided with proper food, shelter and care, when this is done on a large scale it is called animal husbandry.

16. Silo:
Harvested grains are usually dried before being stored because moisture encourages the growth of microorganism. They are then stored in metal or earthen container, gunny bags. Such stores are also called silo.

17. Granaries:
The harvested grain, usually stored in huge stores, after they are properly dried in sunlight. Such stores are called granaries.

18. Fumigation:
Fumigation is most effective method for checking the growth of insects by providing smoke or in gaseous state of chemicals without affecting the grain. 

Q.1. Select the correct word from the following list and fill in the blanks.

                            float, water, crop, nutrients, preparation
  1. The same kind of plants grown and cultivated on a large scale at a place is called ………...   .
  2. The first step before growing crops is ……………. of the soil.
  3. Damaged seeds would  …………. on top of water.
  4. For growing a crop, sufficient sunlight and …………   and  …………. form the soil are essential.  
Ans.   (a) crop                                 (b) preparation
           (c) float                                (d) water, nutrients.
Q.2. Match items in column A with those in column B.
Column AColumn B
  1. Kharif crops
  2. Rabi crops
  3. Chemical fertilisers
  4.  Organic Manure
  1. Food for cattle
  2. Urea and super phosphate
  3. Animal excreta, cow dung urine and plant waste
  4. Wheat, gram, pea
  5. Paddy and maize
Column AColumn B
  1. Kharif crops
  2. Rabi crops
  3. Chemical fertilisers
  4. Organic Manure
  1. Paddy and maize
  2. Wheat, gram, pea
  3. Urea and super phosphate
  4. Animal excreta, cow dung urine and plant waste
Q.3. Give two examples of each:
            (a) Kharif crop                             (b) Rabi Crop

 Ans.   (a) Paddy, maize                           (b) Wheat,gram.                 
Q.4. Write a paragraph in your own words on each of the following:
            (a) Preparation of soil                  (b) Sowing
            (c) Weeding                                  (d) Threshing

   (a) Preparation of Soil: It is necessary to prepare soil before growing a crop. It involves tilling and loosening the soil. This allows the roots to penetrate deep in the soil. The loose soil allows the roots to breath easily even when they are deep. The process of loosening and tilling of the soil is called tilling or ploughing. This is done by using a plough.

           (b) Sowing: Sowing is the process of putting seeds in the soil. The tool used traditionally for sowing seeds is shaped like funnel. The seeds are filled into the funnel, passed down through two or three pipes having sharp ends. Now-a-days a seed drill is used for sowing with the help of tractors. This tool sows the seeds uniformly at a proper distance and depth.

(c) Weeding: The undesirable plants grown along with the crop are called weeds. The removal of weeds is called weeding. Weeding is necessary, since weeds compete with the crop plants for water, nutrients, space and light. Thus, affecting the growth of the crop.

(d) Threshing: The process of separating the grain seeds from the chaff is called threshing. Traditionally it is done by winnowing. Nowadays this is carried out with the help of combined harvesters. Which a combination of harvester and thresher.

Q.5. Explain how fertilizers are different from manure.

  1. Fertilizers are chemicals which are rich in a particular nutrients like nitrogen phosphorus and potassium.
  2. Excessive use of fertilizers destroys soil fertility.
  1. Manures are decomposed organic matter obtained from plant or animal waste.
  2. The use of manures improves soil texture as well as its water holding capacity.
Q.6. What is irrigation? Describe two methods of irrigation which conserve water.
Ans.Irrigation: Supply of water to crops at appropriate intervals is called irrigation. Two methods which help us to use water economically are:
  1. Sprinkler System:This system is more useful on the uneven land where water is available in smaller quantity. The perpendicular pipes, having rotating nozzles on the top, are joined to the main pipeline at regular intervals. When the water is allowed to flow through the main pipe with the help of a pump, it escapes from the rotating nozzles. It is sprinkled on the crop as if it is raining. Sprinkler is very useful for the sandy soil [Fig. 1.8.].

Fig. 1.8.Sprinkler system
  1. Drip System:In this system, the water falls drop by drop just at the position of the roots. So, it is called drip system. It is the best technique of watering fruit plants, gardens and trees. This system consists of a main pipe to which lateral pipes are joined. The specially prepared nozzles are attached to these lateral pipes. The nozzles are grounded just near the roots of the plants. It provides water to plants drop by drop. Water is not wasted at all. So, it is a boon in regions where availability of water is poor. [Fig. 1.9.].

Fig. 1.9.Drip system

Q.7. If wheat is sown in the kharif season, what would happen? Discuss.

We know that India is a vast country. The climate condition like temperature, humidity and rainfall vary one region to another. Accordingly, there is a rich variety of crops grown in different parts of the country and different season, so if wheat is sown in June to September then production of wheat will be lesser than the best climate during October to March.
Q.8. Explain how soil gets affected by the continuous plantation of crops in a field.

Since, crops take up nutrients from soil, continuous growing of crops makes the soil poorer in certain nutrients.
Q.9. What are weeds? How can we control them?

In a field many other undesirable or unwanted plants may grow naturally along with the crop. These plants are called weeds. We can adopt many ways to remove weeds and control their growth. Tilling before sowing of crops helps in uprooting and killing of weeds, which may then dry up and get mixed with the soil. The best time for the removal of weeds is before they produce flowers and seeds. The manual removal includes physical removal of weeds by uprooting or cutting them close to the ground, from time to time. This is done with the help of a khurpi or a harrow.
Weeds are also controlled by using certain chemicals, called weedicides like 2, 4-D. These are sprayed in the fields to kill the weeds. They do not damage the crops. The weedicides are diluted with water to the extent required and sprayed in the fields with a sprayer. (Fig. 1.7)
Q.10. Arrange the following boxes in proper order to make a flow chart of sugarcane crop production.

Sending crop to
Suger factory
 Irrigation Harvesting Sowing
                  1                                 2                             3                     4
Preparation of    soil
 Ploughing the field Manuring
           5                                  6                              7


Ploughing the field
 Preparation of soil Sowing Manuring
                    6                          5                            4                         7
 Harvesting Sending crop to suger factory 
                     2                      3                           1
Q.11. Complete the following word puzzle with the help of clues given below.
  1. Providing water to the crops.
  2. Keeping crop grains for a long time under proper conditions.
  3. Certain plants of the same kind grown on a large scale.
  1. A machine used for cutting the matured crop.
  2. A rabi crop that is also one of the pulses.
  3. A process of separating the grain from chaff.


Q.1. What does agriculture mean?
Ans.In Latin word alter means field and culture to means cultivate. Thus, agriculture means to cultivate a field.
Q.2. How can we reduce loss of grains due to eating away by rodents?
Ans. By the use of storage bins and godowns.
Q.3. Name two common examples of agricultural crops.
Ans.Wheat, Rice, Barley etc.
Q 4. What are crop plants?
Ans.The plants grown on a large scale in the vast fields are called crop plants or simply crop.
Q.5. What is a crop?
Ans.A cultivated produce from the ground is called a crop.
Q.6. What precaution should be taken while using grain, fruits and vegetables brought from the field to the market?
Ans.They should be washed well to make them free from pesticides.
Q.7. What does a plant need to grow well and healthy?
Ans.Oxygen, water, sunlight and nutrients from the soil.
Q.8. Define fertilisers.
Ans.Fertilisers are chemical substances rich in soil nutrients, such as potassium, nitrogen and phosphorus. It is used to improve the production of crops and the soil fertility.
Q.9. What is tilling or ploughing?
Ans.The process of loosening and turning the soil is called tilling or ploughing.
Q.10. What is hoe?
Ans.Hoe is a simple tool which is used to remove weeds and for lossening the soil. It has a long rod or wood or iron.
Q.11. What is crumbs?
Ans.The ploughed field may have big pieces of soil called crumbs.
Q.12. Write some useful tools used in ploughing and levelling.
Ans.Wooden plough, iron plough, soil plank.
Q.13. What are weeds?
Ans.Weeds are the unwanted plants that germinate and grow in the crop field and share nutrients and sunlight with our crop.
Q.14. Why is it necessary to remove weeds from our fields?
Ans.If weeds are not removed from our fields they will take the nutrients from the soil besides air and sunlight. Thus, our crop may fall short of nutrients and sunlight.
Q.15 . What are pests? How are they harmful?
Ans.Pests are the insects or rodents that destroy much of our crop yield. Thus, it is necessary to save crops from pests.
Q.16. When is the crop normally harvested in the two seasons?
Ans.The Rabi crops are normally harvested in March /April while the Kharif crops are harvested at the end of monsoon, i.e., in September /October.
Q.17. What is harvesting?
Ans.The cutting of crops after maturity and stored is called harvesting.
Q.18. Name some harvest festivals.
Ans. Pongal, Baisakhi, Holi, Diwali, Nabanya and Bihu are harvest festivals.
Q.19. Why prayers and religious rites are held at many places during harvesting season?
Ans.To offer thanks to the Gods for the bountiful harvest.
Q.20. How is harvesting crop brought to the ground?
Ans.They are cut close to the ground by using a sickle or mechanical harvester.
Q.21. How is thrashing done?
Ans.Thrashing is mostly done with the help of a machine called thrasher or a motorised machine called combine. These separate the chaff from grain.
Q.22. What is thrashing?
Ans.The process of separation of grain from the chaff in the harvested plant is called thrashing. For this process, a machine called thrasher or a motorized machine called combine are used.
Q.23. What do you understand by the term field fallow?
Ans.Leaving the field without growing any crop on it for a season or two is known as field fallow. In this the field is allowed to take rest and replinished its nutrient resources.
Q.24. Which microorganisms cause diseases in plants?
Ans. Bacteria, virus and fungi.
Q.25. How are diseases transmitted in plants?
Ans.Through seeds, soil and air.
Q.26. Name three pesticides which can be used without affecting the animals or plants.
Ans.Malathion, Disyston, BHC (Benzenehexachloride).
Q.27. Define pesticides.
Ans.Pesticides are chemicals which can kill organisms called pests like insects, rats and birds.
Q.28. Name some weedicides.
Ans.   i.2-4D (2, 4-Dichlorophenoxyacetic acid)
Q.29. Can some method, other than use of insecticides be used to control pests?
Ans.Biological methods have been tried to control insect population by attracting male into a trap, containing small amount of female hormone.
Q.30. Can sound also be useful in saving crops from insects or rodents?
Ans. Chinese have used some particular frequency of sound to scare away rats by its irritating noise from the crop fields. Birds can easily be scared away by sound.
Q.31. Distinguish between pesticides and weedicides.
Ans.Weedicides kill weeds while pesticides kill pests. Both are useful for the production of crops, but are harmful in its use by farmers.
Q.32. What are biocides?
Ans.The pesticides produced by living organisms which would kill only specific pests without affecting other organisms, especially humans, are called biocides.
Q.33. Why should we not use excess of pesticides?
Ans.Because indiscriminate use of pesticides and fertilisers may lead to environmental degradation, This may even make pests resistant to pesticides and make them ineffective.
Q.34. How do fertilisers used pollute water?
Ans.Excess of fertilisers are washed away into the surrounding water bodies. Thus, concentration of nitrates and phosphates in the ground and surface water increases making it unfit for use.
Q.35. Why Harvest Festivals are celebrated with great enthusiasm?
Ans.Because at that time the people are jubilant to see the crop laden with grains. They are happy because their hardwork had borne fruits. Thus, people celebrate these with great enthusiasm.
Q.36. What is a manure?
Ans.Manure is a material formed by the decomposition of waste products of plants and animals such as excreta, cowdung, urine, plant wastes and other organic material. This is added to the soil to enrich the soil in nutrients, and to improve the production.
Q.37. Name some plant diseases and the organisms causing them.
Ans.  (i) Wilt is a disease caused by bacteria which block the transport of water through the pant xylem.
         (ii) Rust of wheat is caused by fungi.
        (iii) Blight of potato is caused by fungi.
Q.38 . Why do we grow different plants in different parts of India?
Ans.The requirements of different types of plants vary considerably. Some need hot  regions while others can grow only in cold regions. Some needs more water and some can survive in scarcity of water. Thus, we grow the crops or plants according to the habitat in different  regions of India.
Q.39. What is humus? How is it formed?
Ans.Humun is the top layer of the soil formed by decaying or decomposition of organic matter like leaves or animal remains or dead organisms, dead animals, dead plants, shed leaves or organisms by the microorganisms.
Q.40. Why should we use organic manure?
Ans.Since, organic manure is obtained from organisms, it is simple recycling of nutrients through soil. As such characteristics and texture of soil is not disturbed. Further, vegetables and fruits grown by using organic manure are safer to eat.
Q.41. What are important conditions for ensuring better yield of crops?
Ans.Good and right kind of soil, seeds, water and protection from weeds and pests and use of proper modern implements and practices are important for good crop yield.
Q.42. Why do we level the soil after ploughing and how we do it?
Ans.The land after ploughing is leveled with the help of tractors and even sometimes with the plough attached mechanism. This is necessary to prevent soil from being blown away by wind or drained off by water.
Q.43. What do you understand by the term decomposers?
Ans.Some microorganisms like bacteria, fungi or even some worms decompose, i.e., breakdown the dead leaves, animal remains and wastes into simple compounds and forms carbon, nitrogen and other chemicals. Such microorganisms are called decomposers.
Q.44. Why do we need to keep requisite distances between two adjoining trees ?
Ans.The plant needs water and nutrients from the soil while air and sunlight from the  atmosphere. For proper growth they need sufficient amount of these materials which is possible only by growing them at a requisite distance. This is why we keep a requisite distance between the two adjoining trees.
Q.45. What precautions we need to observe while sowing seeds?
Ans.The following precautions should be taken while sowing seeds:
  1. Seeds should be grown at proper depth.
  2. They should be sown at a proper distance apart from each other.
  3. Seed used for sowing should be clean, healthy and free from any disease or infection.
Q.46. How can we separate at home the diseased seeds from healthy ones among seeds to be used for our kitchen gardening?

When dip the seeds in a bucket of water some of the seeds float on the top of water while some sink down. The ones that float on water are unhealthy seeds because they are hollow and lighter. Those sink are healthy one.
Q. 47. Why is soil turned and loosened before seeds are sown?

It is necessary to turn and loosen the soil because only loose soil allows the roots to penetrate freely deeper into soil. The roots can breathe easily in loose soil. The deep roots hold the plants more firmly. The water also can reach easily up to more depth in loose soils. Microbes and worms can also grow in loose soil.
Q.48. Why do we need to add manure to the soil?

Manures help in conserving and enriching the fertility of the soil. By growing plants again and again on the same soil, the soil becomes deficient in these nutrients. Thus, it is necessary to replenish the soil with these nutrients, manures are used in conserving and enriching the fertility of the soil.
Q.49. How can we save our crops from these pests?

Use of insecticides or pesticides helps in saving the crops from the pests. Pesticides kill the pests and their eggs selectively without effecting the plants. Some insecticides even prevent the moulting of the insects. Thus they kill them.
Q.50. How and when are insecticides /pesticides sprayed on the fields?

          How are the pests controlled in a crop field?


Fig. 1.10.
Knap-sak sprayer
To control the pest population, it is important to spray pesticides at appropriate time of life cycle of the pest for example: for grasshoppers and mosquitoes, the rainy season is the best time to spray.
            Selection of appropriate pesticide is also important. The pesticides are generally sprayed through various kinds of manual/mechanical sprayer. Knap-sak sprayer (Fig. 1.10) is manually operated and is very common in use these days.
Q.51. What is a Scare-Crow and why is it used for?

It is an artificial statue like structure made of bamboo sticks to which human clothes are worn. This looks like a human being and helps in scaring the field from birds (mistaking it to be a person standing).
Q.52. Why the pesticides be used with great care?

Pesticides may irritate the skin and the respiratory system of man, when the pesticides are used. They reach in the soil and water and absorbed by the plants. These plants, when consumed by man, the chemicals enter into the system and disturb metabolic activities, as well as food chain.
Q.53. How worms and microbes are friends of a farmer?

The worms and microbes are friends of a farmer as they help in making humus to enrich soil with nutrients. Some even loosen the soil like earthworm. Even the dead bodies of these contribute to the formation of humus. The excreta of earthworm too make the soil fertile.
Q.54. How has the uses of fertilisers improved crop production?

Use of fertilisers compensate for replenishing soil nutrients. The nutrients may be depleted by continuous use of the land for growing crops. Thus, to maintain soil fertility the amount or dose of nutrients in the form of chemical fertiliser is necessary. They increase the yield of the crops.
Q.55. How is winnowing done?

The thrashed seeds are thrown slowly after raising it to a certain height in presence of air which separates chaff from the seeds. Due to gravity of earth the heavy seeds all straight to the grounds while the light chaff is blown a little farther away by wind. The density of the material is an important factor.
Q. 56. What is the need for storage of food materials?

Generally, the food crops are seasonal. They are available in plenty during a particular period. Therefore, it is the need for storage of food material to provide seasonal foods throughout the year to each citizen at every place of the country.
How does a farmer store the grains?
The presence of less than 14% moisture is suitable for the grains to be in good condition. So a farmer dries the grains in sun and stores them in small metal containers or jute bags. Larger amount of grains are stored in granaries and silos.
Q.58. What would happen to the stocks of nutrients if we grow plants in the same soil year after year?

Nutrients would get depleted by growing plants in the same soil year after year. I adversely affects the ability of the soil to replenished itself and ultimately the crop production, Thus, it is wise practice to leave the land free for sometime or to apply different other practice, like crop rotation, etc.
Q.59. How enlightened management of land is essential for sustaining good crop yields year after year?

Ploughing the soil makes it aerated and easy to manure. Ploughing soil is then leveled for uniform and easy irrigation. The top soil is very much important for plant growth, It contains nutrients. If it is lost by wind or water erosion, it would adversely affect the crop production. Thus, enlightened management of land is essential for sustaining good crop yields year after year.
Q.60. Why does a farmer rotate crops in a field?

Repeated growing of the same crop depletes the soil of specific nutrients, But rotating different crops in the same piece of land in same year replenishes the soil naturally. Generally, the leguminous crops are alternated with other crops because the legumes have nitrogen fixing bacteria in their roots which converts atmospheric nitrogen into nitrates thus increasing nitrogen strength in the soil.
Q.61. Why should the harvested grains be protected from moisture?

The harvested grains should be protected from moisture because it promotes the growth of moulds (fungi) on grains. Some of the fungi which grow due to moisture on grains may be poisonous.
Q.62. How is Field Fallow helpful in replenishing the soil?

. When we leave the field undisturbed without growing any crop on it, a lot of humus grow in it along with soil bacteria. This way soil becomes rich in nutrients. Thus, vitality of the soil is regained for the next crop. This way field fallow helps in replenishing the soil.
Q.63. How does fumigation differ from spraying?

Fumigation is the most effective method for checking the growth of insects in stored grain. It kills the insect without affecting the grain. Spraying is more suitable to disinfect the storage structure before arrival of fresh stock of food material.
Q.64. What steps are taken to protect crops from pests?

Crops from pests are protected by:
  1. Raising scarecrows.
  2. Beating of drums.
  3. Spraying dilute solution of pesticides.
Q.65. List some important requirements for a field needed to grow plants.

. Some of the important requirements of a good field are:
  1. Openness:Field should be open so that air, light etc. can reach properly to each plant.
  2. Well Protection:So that stray cattle/other animals and man do not destroy crop.
  3. Ploughed Well:So that soil is loosely held and young plant roots can easily penetrate into the soil and are well ventilated.
  4. Irrigated Well:So that nutrients can easily be taken up by plants. Irrigation should neither be too much nor too less.
  5. Healthy Soil:Soil should have enough nutrients to fulfill the requirements of the plants.
  6. Weeds should be removed.
Q. 66. Name the seasons for cultivating crops in India.

There are three main seasons in India for growing crops:
  1. Kharif Season-beginning in June-July.
  2. Rabi Season-beginning in October-November.
  3. Summer Season or Zayed Season-beginning in April-May.
Q.67. What do you understand by the term “Irrigation”? How much water should be given to crops?

Irrigation: Irrigation means giving proper amount of water to our agricultural crops. Fields are irrigated by water from canals, water-ways or from wells.
         Bunds and Furrows are important methods of irrigation.
         Neither too much nor too little water can give us good yield. Excess of water destroys crops and thus, it should be drained off by providing suitable outlet. Some plants like paddy (rice), tea etc., need to be partially submerged in water. Bunds and furrows are important in these cases.
Q.68. How are weeds removed from fields? What is this process called?

. Process of removing weeds is called weeding. It is done (i) by hand (ii) with the help of trowel as shown in Fig. 1.11 (a) (iii) by using a Harrow as shown in Fig. 1.11 (b) (iv) use of weedicides.

Fig. 1.11.
(a) Hand picking and use of trowel            Fig.1.11 (b) Harrow weeding
Q.69. How is our food production or crop yield increasing day by day?

  Our food production is increasing day by day because:
  1. We have increased area under cultivation.
  2. We are using better quality seeds.
  3. we are employing scientific methods to improve soil fertility.
  4. plants are protected against pests.
  5. We are using better storage facilities.
  6. Controlled plant diseases.
Q.70. State two indications of damage by insects and microorganisms in stored foodgrains.

There are two indications of the presence of insects in stored foodgrains:
  1. Patches of white powdery material can be observed on the bags or on the floor of store.
  2. The grain temperature increases.
  3. Presence of weevilled grain, webs, cocoons, dead or living insects in the stored food material.
Q.71. How is the population of insects and microorganisms controlled in stored foodgrains?

The population of insects and microorganisms is controlled by the following ways:
  1. The store as well as foodgrain materials should be free from insect and microorganisms.
  2. The stored grains should be regularly checked to detect the presence of insects.
  3. Pesticides and fumigants should be used for controlling pests and insects.
Q.72. How do fumigant act on stored grain? How do we use ethylene-dibromide?

Fumigants are volatile chemicals and they vapourise killing the insects without affecting the grain. 3 mL of EDB would be sufficient to fumigant one quintal of stored grain whereas 5 mL for one quintal paddy. The certain ampules of EDB wrapped in cloth are inserted little below the surface of the grain to be fumigated. Now, the structure is made to, be airtight.
Q.73. How are pests controlled in a crop field?

    1. By treating seeds with chemicals before sowing them.
           2. Spraying pesticides as Malathions, Disyston, BHC
at a proper time.      
           3. Use of particular frequency of sound or chemicals to scare away rats from crop field.
Q.74. Give different ways of irrigating a crop in the field.

   (i) Lift irrigation                         (ii) Water wheel
         (iii) Swinging basket                   (iv) Sprinkler
          (v) Tubewell.
Q.75. How was agriculture started as a regular activity of cultivation of food plants ?

In the early stages of civilisation humans had no community life. They used to live or wander from place to place. They used to eat whatever available such as plants, fruits, leaves, stems or animals. Due to security reasons and other factors they started to live together and for convenience they started settling near water resources. This prompted theme to learn and grow plants near their place of residence. Slowly after acquiring more experience they started cultivation in bigger areas. Thus, agriculture was started as a regular and systematic activity with passage of time.
Q.76. How do you control the weeds?

Weeds can be controlled by:
  1. Tilling of crops before sowing. This helps in uprooting the weeds which dry up and are killed.
  2. Weeding or removal of weeds should be done before they produce flowers or seeds. Dry weather is favourable.
  3. Physical removal of weeds should be done from time to time using khurpi or a tractor driver harrow.
  4. Rotation of crops also help in controlling weeds.
  5. Weedicides i.e., chemicals to control weeds, should be sprayed in the fields during vegetative growth of weeds before flowering or seed formation.
Q.77. Explain the process of harvesting and thrashing.

Harvesting: The removal of crop after maturity is called harvesting. The harvesting differs from crop to crop, e.g.,
  1. Harvesting is done manually using ordinary sickle in crops like wheat, paddy and maize.
  2. Tractor driven machines are used to harvest wheat and paddy.
  3. Fruits and vegetables are plucked manually.
        Thrashing: The separation of grains from chaff is called thrashing. On a small scale can be it done by winnowing
In some cases both harvesting and thrashing is done simultaneously by machines called Combine.
However, combines should be avoided in case of wheat as it gives less amount of fodder.
Q.78 Why proper storage of food grains is important? How is it done?

Storage of produce is an important task. If the crop grains are to be kept for longer time, they should be safe from moisture, insects and rats. The fresh crop has more moisture. If freshly harvested grains (seeds) are stored without drying, then they may get spoilt or they may lose their germination capacity. Hence, before storing them, the grains are properly tried in the sun to reduce the moisture in it. This prevents the attack by insect pests, bacteria and fungi. Farmers store their grains in jute bags or metallic bins. However, large scale storage of grains is done in silos and granaries to protect them from pests like rats and insects.
Dried neem leaves are used for storing food grains at home. For storing large quantities of grains in big godowns, specific chemical treatments are required to protect them from pests and microorganisms.

 Q.1. Fill in the blanks with appropriate words:

  1. .....................  are the activities used for cultivation of crops.
  2. …………….  is a process to loosen soil.
  3. …………….  involves putting seeds in soil.
  4. ……………. is organic matter obtained from plant or animal wastes.
  5. ……………. are chemical substances rich in nutrients such as nitrogen, phosphorus, potassium.
  6. …………… like paddy, maize grow well during June-October.
  7. …………... like wheat, legumes grow well during Nov.-April.
  8. …………. include all plants other than the crop.
  9. …………. is removal of weeds.
  10. ………….. are chemicals to control growth of weeds.
  11. …………..  are plant products to replace weedicides.
  12. …………..  are chemicals that kill pests which damage crop.
  13. .................. is cutting off the crop after it has matured.
  14. ………….. is a device to spread seeds in soil.
Q.2. Match the following items given in Column ‘A’ with that in Column ‘B’:

Column AColumn B
  1. Plough
  2. Hoe
  3. Cultivator
  4. Seed drill
  5. Moat
  6. Sickle
  7. Sprayer
  8. Combine
  1. Sowing of seeds
  2. An irrigation system
  3. Manual harvesting
  4. Loosening and turning of soil
  5. Used for spraying weedicide
  6. Removing weeds
  7. Combined harvester and thresher
  8. Tractor driven tilling device
Q.3. State whether the statements given below are True or False:

  1. Various kinds of plants grown at a place constitute a crop.
  2. Supply of water to crops at appropriate intervals is called irrigation.
  3. Weeding involves removal of weeds (unwanted and uncultivated plants).
  4. Harvesting is the cutting down of the mature crop.
  5. Removal of the grains from the chaff is called threshing.
  6. Proper storage of grain. is necessary to protect them from pests and microorganisms.
  7. Sowing of seeds at varying (different) depth and distance gives good yield.
  8. It is better to use fertilisers than organic manure.
Q.4. Choose the correct option in the following questions:

i. The process of loosening of the soil is called

a) tilling                                                             b) harvesting
c) spraying                                                         d) weeding
ii. Which is pesticides?

a) 2,4-dichlorophenoxyacetic acid                    b) Malathion
c) Metachlor                                                     d) Chloroform
iii. Seed drill is used for

a) harvesting                                                      b) cleaning the seed
c) sowing                                                           d) weeding
iv. Rabi crop is harvested in

a) January                                                          b) March
c) October                                                         d) September
v. Maize grow well during in

a) June                                                               b) January
c) April                                                              d) September
vi. The agricultural instrument used for removal of weed is

a) sickle                                                             b) khurpa
c) seed drill                                                       d) plough
vii. Transplantation of seedling is done in

a) coffee                                                            b) cocoa
c) rice                                                                d) mango
viii. Compost is a

a) manure                                                          b) fertilizer
c) pesticide                                                        d) weedicide
ix. BHC (Benzene hexachloride) is a

a) weedicide                                                      b) fertilizer
c) fungicide                                                       d) pesticides
x. The chemical substances rich in nutrients are called

a) fertilizer                                                        b) weedicide
c) pesticides                                                      d) herbicides
xi. The process of separation of grain from the chaff after harvesting is known as

a) tilling                                                            b) thrashing
c) spraying                                                       d) weeding
xii.  The soil matter formed by decayed organic matter is called

a) pesticides                                                      b) fertilizer
c) humus                                                           d) biocide
xiii.Supply of water to crops of appropriate interval is called

a) cultivation                                                     b) irrigation
c) harvesting                                                     d) sowing
xiv.Which simple tool is used to remove weeds?

a) Sickle                                                            b) Plough
c) Hoe                                                               d) Seed drill
xv.  Which instrument is used for spraying weedicides?

a) Sprayer                                                          b) Cultivator
c) Plough                                                           d) Combine
Q.1. Fill in the blanks:

  1.   Agricultural practices                  ii. Tilling                             iii. Sowing
  2. Manure                                         v. Fertilisers                        vi. Kharif crops
  3. Rabi crops                                 viii. Weeds                             ix. Weeding
  4. Weedicides                                  xi. Herbicides                      xii. Pesticides
  5. Harvesting                                xiv. Seed drill.
Q.2. Match the items under Column ‘A’ and Column ‘B’:

Column AColumn B
  1. Plough
  2. Hoe
  3. Cultivator
  4. Seed drill
  5. Moat
  6. Sickle
  7. Sprayer
  8. Combine
  1. Loosening and turning of soil
  2. Removing weeds
  3. Tractor driven tilling device
  4. Sowing of seeds
  5. An irrigation system
  6. Manual harvesting
  7. Used for spraying weedicide
  8. Combined harvester and thresher
Q. 3. True or False:

     i) False                ii) True             iii) True                  iv) True         v) True   
   vi) True               vii) False          viii) False
Q.4. Choose the correct option:

      (i) (a)                   (ii) (b)                  (iii) (c)                (iv) (c)                   (v) (a)
    (vi) (b)                 (vii) (c)                 (viii) (a)               (ix) (d)                   (x) (a)
    (xi) (b)                 (xii) (c)                 (xiii) (b)              (xiv) (c)                 (xv) (a).