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)
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
View Full Answer(1)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?
1.Plot B shows a sudden increase in the yield percentage of crop because when chemical fertilizers are used on the crop, they boost the yield suddenly; however, 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 required 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, enriching 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.
View Full Answer(1)Suggest some preventive measures for the diseases of poultry birds.
Poultry birds are highly susceptible towards diseases caused by virus, fungi, bacteria and parasites along with nutritional deficiencies. In order to prevent these diseases, farmers can take the below mentioned measures:
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?
In the case of large-size poultry birds with no summer adaptation, the egg production will decline significantly and the cost to keep the poultry farm will go up. As no summer adaptation will lead to extra cost of maintaining the farm temperature and creating a controlled environment. The large size of the birds will require a huge quantity of diet in order to get the necessary nutrients and fibre.
Crossbreeding of birds is done to achieve a breed that is smaller in size and adaptable towards summer.
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Name two types of animal feed and write their functions.
Dairy animals have certain food requirements which are categorised into two types:
1. Maintenance requirement: The food which is required by an animal for nutrients and a balanced diet for a healthy life.
2. Milk-producing requirement: The food required specifically for the lactation period.
This feed includes:
They are also known as the Dietary fibre. Roughages are indigestible and coarse ingredients which provide bulky feeds in the diet of an animal. They promote regular bowel functions. The common examples of roughages in animal feed are silage, grass and hay.
They are a mixture of protein and other nutrients concentrated at a very high level. Concentrates are low in fibre however are a significant part of the balanced diet of an animal. The common examples of concentrates in animal feed are maize, rice bran and gram husk.
View Full Answer(1)Discuss why pesticides are used in very accurate concentration and in very appropriate manner?
To counter the effect of insect pests and fungi on crop production, chemical substances known as Pesticides are used generally. The common types of pesticides include insecticides, fungicides and herbicides. They are sprayed across the crop for treating soil and seed. An accurate and prescribed concentration of these pesticides should be used on the crop and soil as excessive usage of this chemical can lead to poisoning of plants and animal in the zone. Excessive usage of pesticides leads to reduction of the organic matter. As these chemicals are poisonous, they can cause an intense environmental pollution if used in excess.
View Full Answer(1)Write the modes by which insects affect the crop yield.
Crops are affected by insects in three ways:
Insect pests damage various plant parts like the roots, leaves, and stems, which disrupts essential processes like photosynthesis. This interference limits the plant's ability to produce food, reducing its growth and development, and consequently decreasing the plant's overall productivity.
Insects often attack the cell sap of plants, feeding on the nutrients contained in different plant parts. This leads to a depletion of essential resources, resulting in poor crop yields. The loss of nutrients hampers the plant's growth, leading to weaker plants and fewer fruits or seeds, ultimately affecting agricultural output.
Certain insect pests, such as borers, burrow into the fruits and stems of plants. This damage disrupts the plant’s internal structure, making it more prone to diseases and decay. The result is a reduced crop yield as the damaged parts of the plant become less productive or even unmarketable, impacting both the quantity and quality of the harvest.
Why bee keeping should be done in good pasturage?
The pasturage is the piece of land where the flowers are grown in order to provide bees with nectar for the production of honey. The quality or value of the honey produced is dependent on the flowers in the pasture. If good variety flowers are provided to bees for nectar and pollen collection the quality of honey produced will be of higher grade. The variation in types of flowers varies the taste and quality of honey. In order to have a quality yield with varied taste of honey, farmers are required to have different flowers at the pasturage.
View Full Answer(1)What do you understand by composite fish culture?
Composite fish culture is the farming of fish in a system where a blend of 5 or 6 fish species are raised in a single pond. The selection process of these species is done on the basis of competitive attributes and feeding patterns. This selection is done to prevent any competition amongst the selected species which leads to availability of food for all the fishes.
Example: Surface feeders such as Catlas are mixed with column feeders such as Rohus, Mrigals, Grass Carp which are bottom feeders. This combination leads to an efficient utilisation of food present in the pond and enhances the yield of fish from pond.
The major problem with composite fish culture is the unavailability of quality seed. This has been resolved by the use of hormonal stimulation of fishes in the pond itself leading to a pure seed of each species in desired quantities.
View Full Answer(1)Give the merits and demerits of fish culture?
Fish culture is a manmade process of raising fish in a controlled environment. The desired species of fish are raised inside man-made ponds or fish tanks. It is also termed as pisciculture.
Merits of fish culture:
Demerits of fish culture:
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Missing Numbers from figure / Figure Matrix
Suggest some preventive measures for the diseases of poultry birds.
Name two types of animal feed and write their functions.
Discuss why pesticides are used in very accurate concentration and in very appropriate manner ?
Write the modes by which insects affect the crop yield.
Why bee keeping should be done in good pasturage ?