CBSE Class 9 Science Revision Notes Chapter 15

CBSE Class 9 Science Revision Notes Chapter 15 – Improvement in Food Resources

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CBSE Class 9 Science Chapter 15 – Improvement in Food Resources Revision Notes 

Access Class 9 Science Chapter 15 – Improvement in Food Resources Notes

  • Improvement in Crop Yields:   

For optimal development and life cycle, different crops require different climatic conditions, temperatures, and photoperiods. Crops planted in the rainy season, which happens from October to June, are known as Kharif crops. Some examples of Kharif crops include soya beans, paddy, and Cotton. These crops, which are planted from November to April, are known as Rabi crops, including peas, wheat, gramme, and linseed. Three key groups of efforts are required to increase crop yield, i.e., crop variety improvement, crop production improvement, and crop protection management.

  • Crop variety improvement:

Crops variety improvement can be achieved by selecting process. Certain factors that lead to variety improvement include higher yield, increased quality, biotic and abiotic resistance, change in maturity duration, wider adaptability, and desirable agronomic traits. Hybridisation happens due to inter-varietal crossing, where there is a mix between two different varieties, or inter-generic crossing, where there is a mix between two separate genera, or inter-specific crossing, where there is a mix between two separate species. If beneficial genes are implanted in a crop, its output can be boosted. This results in genetically engineered crops being made.

  • Crop Production Management:

It means protecting growing and harvested crops. Nutrient management, irrigation, and cropping patterns can help improve crop output. 

Various actions done by farmers to produce crops are known as agricultural practices. These include the following activities.

  • Preparation the soil 
  • Sowing 
  • Addition of fertilisers and manure
  • Irrigation 
  • Protection against weeds 
  • Harvesting 
  • Storage 

The quality of the soil, seeds used, and procedures used for planting determine the overall strength of the crops and their growth. For example, corn can survive harsh conditions and increase yields by using strong hybrid seeds. While there is a significant advancement in seed science, farm efficiency can still be improved using suitable approaches and methods. 

  • Nutrient Management:

Air, water, and soil are plants’ main sources of nutrition. There are two types of nutrients found in plants, i.e., macronutrients and micronutrients. Both carbon and oxygen are provided by air. Both hydrogen and oxygen are found in water. The rest of the 13 nutrients are found in soil. Nutrition deficiency affects various plants’ physiological activities such as reproduction, growth, and disease susceptibility. By adding these nutrients through manure and fertiliser, the quality of the soil can be increased.  

  • Manure :

When animal excreta and plant waste decompose, manure is created. Manure consists of organic matter that increases water retention in sandy soils and prevents water from logging in clayey soils. The composting process can be aided by decomposing waste, including farm waste, vegetable waste, household garbage, and sewage waste. Vermicompost is created by using earthworms so that the decomposition of plants and animals can be done quicker by using the vermicomposting process. By sowing nitrogen and phosphorus-rich plants in the soil, green manure can be provided to plants.

  • Fertilisers:

Fertiliser gives nitrogen, phosphorus and potassium to plants. They are used to promote healthy plant growth by ensuring better vegetative growth. Fertilisers play an essential role in better yields in high-cost farming. Organic farming uses organic manures, recycled farm wastes, and bioagents with the minimum usage of chemicals, including fertilisers, herbicides, insecticides, and other pesticides.

  • Irrigation:

The predicted yield of any crop can be increased by ensuring that proper water is given at the right time during the growing season. Both modern and old ways can be used for irrigation. Water is supplied to agricultural regions utilising an irrigation system, subject to the type of available water resource. Some examples of water resources include rivers, canals, ponds, lakes, tanks, dams, and groundwater. 

  • Cropping Pattern:

Some examples of cropping patterns include mixed cropping and crop rotation. Mixed cropping is used when two or more crops are grown single plot of land. Some examples of mixed cropping include wheat and gram, peanut and sunflower. Two or more two crops are grown on a single field simultaneously while alternating the rows of one crop with another is known as intercropping. An example of inter-cropping can be soya beans and maize. Finally, when two or three crops are sown on the same land over a year is known as crop rotation. Some examples of crop rotation is cereals and legumes. 

  • Crop Protection Management:

Those unwanted plants that compete for food, space and light with crop plants are known as weeds. Herbicides and mechanical weed removal are used to remove weeds. For example, Xanthium. Specific pathogens like bacteria, fungi, and viruses can cause plant diseases. Such pathogens can be eliminated by herbicides, fungicides, and insecticides. In addition, methods such as good seed, preparation of the bed, sowing crops on time, intercropping, and crop rotation can help manage weeds. 

  • Storage of Grains:

Loss of agricultural storage can be caused by abiotic factors, including insects, rodents, fungi, mites, and bacteria. Such factors can also cause harm to crops, including insufficient factors and temperature in the storage facilities. However, proper treatment of warehouses and management can mitigate such factors.

Preventive and control procedures are taken before grains are stored for future usage. Such procedures include proper cleaning of the product before storage, drying the product in the sun and later in the shade, and pesticide fumigation.

  • Animal Husbandry:

It means scientific management of livestock animals. It includes many activities such as feeding, breeding, and controlling diseases. Some examples of animal-based farming include cattle, goat, sheep, poultry, and fish farming.

  • Cattle Farming:

There are two primary purposes of cattle farming, i.e., milk production and draught labour for agricultural tasks such as tiling, irrigation, and hauling. Farm labour makes use of draught animals, while milk animals give milk. Two commonly used Indian cattle species include Bos indicus, cows, and Bos Bubalis, or buffaloes. Cow management includes cleaning, sheltering, and feeding. Here, cleaning includes regularly washing so dirt and loose hair can be removed. Sheltering includes keeping cattle dry, warmed up, and protected from the sun by using well-ventilated roof sheds. Feeding includes both roughage feed, which consists mainly of fibre, and concentrate feed, which is low in fibre but high in protein.

Many diseases affect cattle. Diseases not only cause death but also limit milk output. Both internal and external parasites can cause diseases. External parasites that exist on the skin’s surface result in skin diseases. Internal parasites are those that cause harm to the stomach and intestine. Vaccines are administered to farm animals for various viral and bacterial infections. 

  1. Poultry Farming:   

Poultry farming refers to the act of keeping chickens for the purpose of eggs and meat. Cross-breeding is very common in poultry so desirable features can be created. Assel, an Indian breed, has been cross-bred with a foreign breed, Leghorn. 

Cross-breeding means a way to produce offspring with a desirable feature. Some desirable qualities may include dwarf boilers that can be used for the purpose of meat in a shorter amount of time, a larger number and quality of chickens, and high-temperature resistance through the summer.

For better poultry production, better management techniques are necessary. These methods include controlling temperature and hygienic conditions, housing and chicken feed, and disease and pest prevention and management. 

  • Fish Production:

Fish species such as tinned real fish and shellfish like prawns and molluscs are produced. There are two main ways through which fish can be acquired. The first way is to capture fish that are based on natural resources. The second way is fish farming, which is also known as culture fishing. 

  • Marine Fisheries:

Some examples of marine fish are mullets, pomfret, mackerel, tuna, sardines, pearl spots, and shellfish like prawns, mussels, oysters, and Bombay duck. There are several high-value fish that are raised in seawater. Some examples of marine fish are seaweeds like elkhorn sea moss, Gracilaria, and Wakame

  • Inland Fisheries:

Often, fish culture is done along with a rice crop that allows fish to grow in the field’s paddy water. However, large-scale fish farming is achievable in a composite fish culture system. In one fishpond, you would have a mixture of five to six different species in this system. 

The surface is fed on by Catla, the middle of the pond is fed on by Rohus, the bottom of the pond is fed on by Mrigals and common carp, and grass carps feed on the pond’s weed.

A hormone simulation strategy is applied to counter the problem of poor-quality seeds in fish farming. With the use of this strategy, pure fish seeds become available in the required amounts. 

  • Bee Keeping:

The act of keeping honey bee colonies within hives is known as beekeeping or apiculture. This usually does not require vast amounts of money. Apiaries, commonly called bee farms, are used to create honey for commercial usage. Wax is produced by beehives that use various therapeutic formulations with honey. 

Apis cercana indica (Indian bee), Apis dorsata (Rock bee), Apis florea (little bee), and Apis mellifera (Italian bee) produce honey used for commercial purposes. 

The quality and worth of honey are determined by the pasturage, or flower nectar and pollen collected by bees, and the variety of flowers decide the taste of honey. 

Improvement in Food Resources Class 9 Notes


Food is necessary for the proper growth and functioning of every living organism. It contains nutrients like carbohydrates, proteins, fats, vitamins, and minerals needed for the body’s development, growth, and maintenance of health. Plants and animals are the main food sources. Raw materials for food are obtained from animal husbandry and agriculture. India has a large population, and it is growing day by day. Therefore, improvements in food resources are necessary to have a higher yield to satisfy the needs of the increasing population. 

Need for Improvement in Food Resources in India

Food needs are also growing each year as the population continues to grow. No extra land for farming is available in India. Production of food must be increased by using sustainable agriculture while not decreasing natural resources and disrupting the balance of the environment. The efficiency of crops and livestock must be raised so a large population can be fed. Several revolutions have occurred due to many scientific breakthroughs and efforts made in agriculture, which have increased food production in all fields.

The green revolution helped raise food production and meet the needs of a growing population. Due to white evolution, there is more accessibility to milk. Due to the blue revolution, there has been a rise in the production of fish. Due to the yellow revolution, there was a rise in the production of oil.  

Improvement in Crop Yield

There are three stages of farm practices that can increase crop production which are –

  • Selection of seed for plantation
  • Taking care of crop plant
  • Protecting growing and harvested plants from loss
  • H3 -Crop Variety Improvement

Crop Variety Improvement

The purpose of this is to identify a species of crops that can sustain in various situations like high salt salinity, different climatic conditions and availability of water and that can give a high yield in the end. There exist two ways that could create required abilities in crops.

  • Hybridisation creates a cross between genetically different plants to make a new variety of crops. It includes inter-varietal crossing, where there is a mix between two distinct types, or inter-generic crossing, where there is a mix between two separate genera or inter-specific crossing, where there is a mix between two separate species.
  • Genetically modified crops include altering crops so their production, quality, and sustainability can increase.

Factors of Crop Variety Improvement

The purpose of this is to identify a species of crop that can be sustained in various situations like high salt salinity, different climatic conditions, and availability of water, and that can give a high yield in the end. There are two ways that could create the required abilities in crops.

Crop production management- It involves controlling different aspects of the production of crops for maximum yield. Higher yield and input application are directly related. Various agricultural practices and technologies can be used by farmers depending on their financial status. 

Nutrient Management- It involves using various methods to raise the level of nutrients in the soil. This can be achieved by using manure and fertilisers. When nutrients are made available to plants through soil, most of them get absorbed. Other nutrients like carbon, hydrogen, and oxygen are made available through water and air.

There are two primary nutrients for the plant.

  • Macronutrients– for proper growth and survival, these nutrients are necessary. They are named so because plants need them the most. These include nitrogen, phosphorus, potassium, calcium, magnesium, and sulphur.
  • Micronutrients– plants need them in smaller quantities. These include iron, manganese, boron, zinc, copper, molybdenum, and chlorine.

Manure– It is an organic substance which is derived from the decomposition of plant wastes like straw and wastes by animals like cow dung.

  • Many organic matters (humus) are received from the soil through manure. 
  • They help in the creation of soil-friendly bacteria.
  • It also helps in improving the texture of the soil.

Fertilisers– These are plant nutrients that are commercially produced. They help in supplying nitrogen, phosphorus, and potassium to the soil. 

  • They increase the production of high-cost farming.
  • They help in giving rise to healthy plants and better ensuring vegetative growth.

Irrigation– It includes the process of supplying water to crop plants through ways like canals, reservoirs, wells, and tube wells.

Cropping patterns– this includes raising crops in a way so that most benefits can arise from the same piece of land. It could be done through mixed cropping, intercropping, and crop rotation.

  1. Mixed cropping- It means harvesting two or more crops on a single piece of land. It is done mainly to keep the risk of total crop failure to a  minimum.
  2. Intercropping- It means a method which involves growing definite patterns of two or more crops at the same time. It is done to raise productivity per unit area.
  3. Crop rotation- It involves harvesting a variety of crops on one single piece of land. It is done to raise the yield from a single piece of land. 

Crop protection management– it includes protecting crops from threats like weeds, insects, pests, and disease-causing organisms. It entails finding ways to reduce the prevalence of these diseases. They can cause a lot of damage if not taken care of on time.

There are two factors that affect grains, i.e., biotic and abiotic factors.

  1. Biotic factors- these involve damage done by insects, rodents, fungi, mites, and bacteria.
  2. Abiotic factors- these involve the presence of inappropriate moisture and temperature in the place where they are stored.

Therefore, there is a need to adopt proper measures for storing. For example, produce should be properly cleaned for storage and properly dried under sunlight before being stored. 


Animal husbandry– Animal husbandry is the scientific management of livestock. 

  • It is necessary to keep up with the demand for animal-based goods like milk, eggs, leather, etc.
  • It helps in reducing input costs.

Cattle farming– cattle farming is used for milk and drought labour by cattle. The primary advantage of cattle farming is 

  • Milk and other milk-based products from cattle 
  • Labour work like tilling, irrigation, and carting on a field.

Poultry farming– It involves nurturing fowl for eggs and meat. The aim of poultry farming is to increase the poultry breed so that more eggs and broilers for meat can be produced. 

  • A broiler means a poultry bird that is used mainly for its meat.
  • A layer means a poultry bird that provides eggs.
  • Foods rich in protein, vitamins K and A and high in fat are necessary for the broiler.
  • Foods rich in vitamins, minerals, and micronutrients are necessary for the skin. They also require proper space and lightning.

Poultry Diseases and their Prevention

Various diseases affect fowl. Such diseases are caused for various reasons, which can influence growth, quality, and quantity. They can also be nutritionally deficient. These can be prevented. 

  • By arranging a proper diet for birds
  • By proper cleaning and sanitation 
  • By vaccinating birds
  • By spraying disinfectant regularly

Fish production– It involves catching and breeding fish for animal-based protein for humans. It is a cheaper source of protein. Fish are captured and cultured by fish farming.

Some methods by which fish can be produced are as follows

  1. Capture fishing- It involves capturing fish for their homes, like ponds, canals, rivers, etc. They can be found and captured by using fishing nets. 
  2. Mariculture- It is a method by which various marine fish varieties can be cultured in coastal water. Large fish are found using satellites and echo sounders and captured using various fishing nets. 
  3. Aquaculture- It means the production of fish from freshwater resources like canals and brackish water resources like estuaries and lagoons. By using simple fishing nets, fish can be located easily and captured. 

Beekeeping– the scientific name of beekeeping is apiculture. It involves cultivating, caring for, and managing honeybees to gather honey, wax, etc. 

The primary benefits of beekeeping are

  • Apart from honey, various other products like wax, royal jelly, and bee venom can also be acquired.
  • Beekeeping generally needs less expenditure, which is why farmers do it along with agriculture as an additional income.
  • It helps with the process of cross-pollination. When bees acquire nectar, pollen is exchanged.

FAQs (Frequently Asked Questions)

1. What are the uses of ‘Intercropping’?

  1. Saving space and resources 
  2. Repelling pests 
  3. Providing nutrients for neighbouring plants

2. What are the disadvantages of ‘weeds’?

  1. Efficiency of irrigation is reduced 
  2. Land value reduces 
  3. Crop production decreases

3. What is the meaning of ‘Organic farming’?

Organic farming is a system of production which avoids or largely excludes the use of synthetically compounded fertilisers, pesticides, growth regulators, genetically modified organisms, and livestock food additives.

4. What causes droughts?

Droughts occur due to water scarcity or low rainfall, often resulting in drought conditions. If farmers do not use any irrigation methods and rely only on rain, drought seriously threatens the crops. Areas with light soils also face drought-like conditions as soils cannot retain water.