What do we get from cereals, pulses, fruits and vegetables?
(i) Cereals - provide us with carbohydrates. They fulfill our energy requirements. Wheat, rice, maize are cereals.
(ii) Pulses - provide proteins, Gram, pea and lentil are pulses.
(iii) Fruits and vegetables provide vitamins and minerals. They also provide small amount of proteins, carbohydrates, and fats are also present in them.
What are the desirable characters of bee varieties suitable for honey production?
Bee varieties having the following desirable characters to be suitable for honey production:
(i) High yield - They should yield high quantity of honey. The bee varieties reared should produce more honey.
(ii) Less Stings - They should not sting much. bees reared should sting less so that they can be reared easily and the honey can be obtained easily.
(iii) Long stay - They should stay in the beehive for long durations.
(iv) Good breeding - They should breed very well.
How do biotic and abiotic factors affect crop production?
Biotic factors such as pests, insects and diseases reduce the crop production. These adverse effect on the plants and thus decrease the production. A pest causes damage to our crops by feeding. Weeds also reduce crop productivity by competing with the main crop for nutrients and light.
Similarly, abiotic factors such as temperature, wind, rain, drought, salinity etc. affect the net crop production. For example droughts and floods have a great impact on crops sometimes, destroying the entire crop. Salinity can lead to the death of crops if they are not resistant to it.
What is genetic manipulation? How is it useful in agricultural practices?
Genetic manipulation is a process in which the gene for a desired character is introduced inside the cell of a plant. The incorporation of a new gene in to the new plant produces a transgenic plant which exhibits the desired characters.
Genetic manipulation is useful as it allows new varieties with desired characters to be produced. It allows in the production of plants with higher yield, good quality, biotic and abiotic resistance, short maturity period, wider adaptability and desirable agronomic characteristics.
What are the advantages of inter-cropping and crop rotation?
Inter-cropping and crop rotation both are used to get maximum benefit on limited land.
Inter-cropping ensures maximum utilisation of the nutrients supplied. It helps in preventing pests and diseases to spread throughout the field. It also increases soil fertility.
Crop rotation prevents soil depletion, increases soil fertility, and reduces soil erosion.
Both these methods reduce the need for fertilizers. It also helps in controlling weeds and controls the growth of pathogens and pests in crops.