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Important questions based on NCERT syllabus for Chapter 1 - Crop Production and Management:
Question-1: How are plants protected from weeds?
Solution: Farmers 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. A seed drill is also used to uproot weeds. Weeds are also controlled by using certain chemicals, called weedicides, like 2,4-D. These are sprayed on 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 spray.
Question-2: Differentiate between mixed cultivation and crop rotation
Solution: In mixed cultivation, two or more different types of crops are sown in a particular field at the same time. For example: pea plants can be grown in the same field along with a cereal like wheat.
Crop rotation is a practice of growing two or more dissimilar crops in the same field one after the other. The nutrient requirements of a particular crop is kept in mind when crops are grown on a rotational basis. For example it is a known fact that paddy uses up lot of nitrogen from the soil. When planning for the subsequent crop to be sown, this fact is kept in mind . So leguminous plants like soya bean or pea are purposely sown so that this loss of nitrogen can be replaced naturally by them.
Question-3: What is the name of plants that grow along with crops but affect the growth of crops? How do they affect growth?
Solution: In the field, many undesirable plants may grow naturally along with the cultivated crop. These undesirable plants are called weeds. The removal of weeds is called weeding.
Weeding is necessary as they compete with the crop plants for water, nutrients, space and light. In this way, they affect the growth of the crop. Some weeds interfere even in harvesting and may be poisonous for animals and human beings. Weeds by the name of Onion Grass, Paddy's Lucerne, parrot's feather, Paterson's curse are commonly seen growing along with crops.