Quality Food, Quality Life – Maharashtra Board Class 9 Solutions for Science and Technology (English Medium)
- Cultivation activities are collective activities spread over a period of time.
- A specific pattern is followed in inter cropping.
- The scientific and systematic management of animal livestock is known as animal husbandry.
- False. (Different crop plants need a different period of exposure to sunlight.)
- False. (A pulse crop helps in enhancing the fertility of the soil.)
- Sudan grass, Rhodes grass, Berseem.
- Apis cerana, Apis florea, Apis dorsata.
- Wilt (Others are crop diseases caused by fungi.)
- Pigeon (Others are species of birds used in poultry farming.)
- Manure is a natural product obtained by organic matter such as cow dung, plant residues and human waste.
- Manure is non-polluting, while chemical fertilisers can cause pollution of soil.
- Manure replenishes the soil with essential elements, adds humus to the soil and improves its texture.
- Manure increases the fertility of the soil, while the continuous use of chemical fertilisers makes it infertile.
- Therefore, the use of manure should be preferred to chemical fertilisers.
- In spite of good agricultural practices, there is scarcity of food as India is a vast country with a large population.
- The requirement of food for such a large population is more.
- To meet this ever increasing demand, more land needs to be cultivated.
- Therefore, to grow more food, India should adopt better agricultural practices.
- India is a vast country with a large population, so it is essential to have food for all. For that we have to take precautions to preserve food by its safe storage.
- The safe storage of food materials facilitates their proper distribution to each part of the country.
- Food materials can be easily damaged by abiotic and biotic factors.
- Therefore, it essential to ensure safe storage of food materials.
Chemical compounds prepared artificially which contain primary plant nutrients are called chemical fertilisers.
Desirable features of chemical fertilisers:
- The chemical fertilisers are compact and concentrated, so they are required in very small quantities.
- They are soluble in water, so they can be readily absorbed by plants.
- We can choose a specific chemical fertiliser according to the type of soil.
- They make the soil more fertile and enhance the growth of plants.
- They are easy to handle.
Undesirable features of chemical fertilisers:
- Chemical fertilisers, if used continuously, make the soil infertile.
- If they are not used in proper proportion, then they can be harmful to plants.
- The organic matter content of the soil is reduced, and natural microbial flora of the soil is lost.
- Excessive use of chemical fertilisers pollutes nearby water bodies.
- Cattle farming in India is practised mainly for milk production and for agricultural activities such as ploughing farms and transport.
- Indian cattle are mainly of two different species – Bos indicus (cow) and Bos bubalis (buffalo).
- Milk-producing females are called milch animals, while male animals used for farm labour are termed as draught animals.
- High-yielding breed of cattle are developed to obtain more quantities of milk. These hybrid breeds are resistant to many diseases.
- Indian cow gives 5 to 6 litres of milk per day, while hybrid varieties give 10 to 12 litres of milk per day.
- Lal Kandhari, Devani, Khillari and Dangi breeds of cows in Maharashtra are selected for hybridisation at the national level.
- High-yielding varieties (HYV) of crops are produced by using the hybridisation technique. Under this technique, two different varieties of crop plants each having the desired characteristic is crossed.
- Due to this technique, a new variety of crop having a combination of the desired characteristics is obtained.
- HYV crops have higher yields, better quality, better resistance to diseases and pests and require a short period of maturation.
- Farmers are switching over to HYV crops as they get more yields in a short duration and thus are commercially benefited.
- Hybrid varieties of rice are Jaya and T 141 and those of wheat are Sonalika, Arjun and Sonora 64.
- Sometimes, crops get infested by pests, weeds and diseases. Pests are organisms which bring damage to the standing crops. The common pests are insects, rodents and birds.
- So, to protect the crops, pests have to be controlled. Two methods of pest control are chemical control and biological control.
- Chemical control of pests is done by using chemical substances called pesticides. Pesticides are sprayed on the crops by using a hand-operated machine or by a power-operated sprayer. Fumigation and dusting are other methods of using pesticides.
- Biological control: This is done by deliberately letting out certain birds, insects or other living organisms which are enemy species of pests. They destroy the pests selectively and save the crops. Though this method is very slow, it is highly specific and does not pollute the environment.
- Weeds are unwanted plants which grow along with the crops in the fields. They are harmful for crops as they compete with the main crop for space, nutrients and sunlight. So, weeds have to be removed by plucking them for protecting the crops. Some common weeds are grass and wild oats.