B.EXERCISE GIVEN AT THE END OF THE CHAPTER
Q1. Explain any one method of crop production which ensures high yield.
Ans. Hybridisation ensures high yield. It is a process of crossbreeding in which two varieties of a crop, each possessing at least one disered character are selected and are cross-bred to incorporate the desired characters in one variety. For example, one variety is taken which is having high yield and the other variety with disease resistance character is taken so that the resulting variety possesses both of these traits.
Q2. Why are manure and fertiliser used in fields ?
Ans. Refer to Q.6., Page 402 (Questions from within the chapter).
Q3. What are the advantages of inter-cropping and crop rotation ?
Ans. In intercropping, two or more crops are simultaneously grown on the same field in a definite row pattern–a few rows of one crop and adjoining to that a few rows of another crop. This practice reduce intraspecific competition i.e. the competition among plants of same crop, for the same type of nutrients. This ensures that both crops can give better yield.
Crop rotation also has its own benefits. It makes the soil fertile and helps in production of crop yield. It also decreases the demand of nitrogenous fertilisers as leguminous plants grown during crop rotation fix the atmospheric nitrogen, thus the soil enrich with nitrogen compounds. Moreover, the selected rotation of crops also helps in pest control, as pests do not find their favourite crop in the next season and it becomes difficult for them to survive there.
Q4. What is genetic manipulation ? How it is useful in agricultural practices ?
Ans. Incorporating desirable characters by hybridisation, mutation, DNA recombination, etc. is called genetic manipulation.
By genetic manipulation, we get improved variety of seeds having desired characters like resistance, and higher yield. There seeds not only give higher yield but also reduce the input cost.
Q5. How do storage grain losses occur ?
Ans. Refer Q. 9. on Page 403 (Questions from within the chapter).
Q6. How do good animal husbandry practices benefit farmers ?
Ans. By animal husbandry we mean scientific management of farm animals. Good animal husbandry practices benefit the farmers in the following ways :
1. Improvement of breeds of the domesticated animals.
2. Reduction is input cost.
Q7. What are the benefits of cattle farming ?
Ans. The main benefits of cattle forming are :–
1. Wet milk from cattle and from it obtain/other milk products like butter, cheese, etc.
2. Bullock labour is used for agricultural practices such as tilling, irrigation and carting.
Q8. For increasing production, what is common in poultry, fisheries and bee keeping ?
Ans. Selection of improved varieties.
Q9. How do you differentiate between capture fishing, mariculture and aquaculture ?
1. It is the process of obtaining fish from the natural resources like ponds, canals, rivers, etc.
2. In capture fish-ing, Fish can be located easily and then caught using fishing nets
It is a practice of culture of marine fish varieties in the open sea.
In mariculture, satellites and echo-sounders are used for locating fish. Then they are caught using many kinds of fishing nets from fishing boats.
It means the pro-duction of fish from fresh water re-sources, like which canals, ponds, reser-voirs, rivers, and brackish water re-sources, like estuaries and lagoons.
Like capture fishing in aquaculture also the fish can be located easily and are caught using fishing nets.
|<< Prev - 1 | 2 | 3 | 4 | 5 - Next >>|