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Crop production and Management Science Mission Part 02 Questions answer Class 08 Book

Science Mission Part 02 Questions answer Class 08 Book

Chapter 01 Crop production and Management


Theoretical Questions

A. Short answer type questions.

1. Differentiate between the following:

i. Compost and green manure

Compost: Compost is the decomposed plant and animal waste which may include waste food, excreta, dried leaves and other organic matter. It is made in a compost pit using microbes.

Green Manure: The green leguminous plants with their root nodules is ploughed along with the soil. The green plants and the root nodules left in the soil decompose to form green manure.

ii. Compost and fertilizers

Compost is a manure prepared by a biological decomposition of organic waste. It takes longer period to absorbed by plants. It is lack of nitrogen, Phosphorous and potash

Fertilizer is manure prepared in factories from chemicals (mineral). It is easily absorbed by soil. It is rich in nitrogen, Phosphorous and potash

iii. Pesticides and weedicides

Pesticides are substances that are meant to control pests, may be fungus, bacteria or animal germs (harmful insects). Weedicides are the chemicals which are sprayed over field to get rid of weeds. Weedicides are poisonous for weeds but not for the crop.

iv. Nitrification and denitrification

Conversion of dead decaying matter into ammonia and then into nitrites and nitrates by nitrifying microbes is called nitrification.

Conversion of nitrites and nitrates from decaying organic matter into gaseous nitrogen by denitrifying microbes is called denitrification.

v. Crops and intercrop

A crop is a plant or animal product that can be grown and harvested extensively for profit or subsistence.

Growing of Trifolium or any other leguminous crop (as green manure) during intervening period in between Kharif and Rabi is intercropping.

2. List the tasks a farmer needs to perform for the cultivation of a crop.

Main tasks to be performed by Farmers before cultivation of crops are

(a) Preparation of soil. (b) Procuring and selection of seeds, (c) Improving soil fertility (d) Irrigation (e) Weeding (f) Protection of crops (g) Harvesting (h)Storage of farm produce.

3. Name one plant each from a kharif crop, rabi crop and the season (month) in which each one of them is (i) sown and (ii) harvested?

Ans: Kharif crop: paddy (rice); It is summer crop. Sown in summer season (May/June and harvested well before onset of winter(September).

Rabi crop: wheat. It is winter crop. Sown well before winter (November end) and harvested in March/April that before onset of summer.

4. What are the different foods which we get from animals?

Ans: Some of the food products obtained from animals are milk, meat including fish, eggs and honey.

5. List some animal sources of sea food.

Ans : Some animals as source of sea food are prawn, crab, oyster etc.

B. Long answer type questions.

1. How and why did humans start practicing agriculture?

Ans: Man was basically a food gatherer. At times when the weather got rough, he and his family had to eat  stale food or had to go without food. This made him to change his habit to domesticating animals and growing plants along his dwelling units. This was the beginning of farming by man.

2. How do we separate healthy seeds from a mixture of seeds?

Ans: Healthy seeds are separated from the mixture of seeds by following :

a. Manually by seeing the physical condition of the seed, damaged seeds are often broken or damaged in other ways.

B. by soaking them in water, damaged seeds are not able for germination process after soaking them.

3. What is intercropping? Name a few crops cultivated as intercrops.

Ans: Planting a leguminous crop in between two major crops in a field such as planting of Trifoliumin between Kharif and Rabi is called intercropping. This way, soil is enriched with nitrogenous nutrients for the next crop in addition to obtaining fodder for the farm animals rich in nutrients.

Intercropping is also a system of cropping where two or more crops are grown in proximity along ridges (as in mixed cropping).

Non-leguminous plant (such as one of Maize (corn), sorghum, millets, potato, cabbage, cauliflower, brinjal) and leguminous plant (such as one of pulses, beans including groundnut) are cultivated alternately as intercrops.



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