Improvement in Food Resources Class 9 Notes Science Chapter 12

Introduction

Improvement in Food Resources refers to the methods aimed at increasing the quantity and quality of food produced through agriculture and animal husbandry to meet the growing demand for food sustainably.

Various Food Resources

As living organisms, food is essential for our growth, health, and overall development. We obtain food primarily from plants and animals through agriculture and animal husbandry. With India's growing population, the demand for food is rising, and it is crucial to find ways to increase food production efficiently.

This chapter focuses on:

• The need to improve crop and livestock production to meet food demand.
• Successes like the Green Revolution and the White Revolutionboosted food and milk production.
• The importance of sustainable practices in agriculture and animal husbandry to protect natural resources.
• The connection between food security, increased production, and access to food.
• Scientific methods like mixed farming, intercropping, and integrated farming improve yields without harming the environment.

Improvement in Crop Yields

Food Crops and their Nutritional Benefits

• Cereals such as wheat, rice, maize, millets, and sorghum provide us with carbohydrates for energy.
• Pulses like gram (chana), pea (matar), black gram (urad), green gram (moong), pigeon pea (arhar), and lentil (masoor) supply us with protein.
• Oilseeds including soybean, groundnut, sesame, castor, mustard, linseed, and sunflower offer essential fats.
• Vegetables, spices, and fruits deliver a variety of vitamins and minerals, along with small amounts of proteins, carbohydrates, and fats.
• Fodder crops like berseem, oats, or Sudan grass are grown for livestock feed.
  Different Types of Crops in India

In India, there has been a fourfold increase in the production of food grains from 1952 to 2010, with only a 25% rise in the area available for cultivation.

Factors Affecting Crop Growth

• Different crops need specific climatic conditions, temperatures, and photoperiods to grow and complete their life cycles. Photoperiods refer to the length of sunlight, which influences plant growth and flowering.
• Plants obtain their energy through photosynthesis, a process that depends on sunlight.
• During the Kharif season (June to October), crops like paddy, soybean, pigeon pea, maize, cotton, green gram, and black gram thrive.
• In the Rabi season (November to April), crops such as wheat, gram, peas, mustard, and linseed perform well.

Major Activities for Improvement:

• Crop Variety Improvement: Enhancing crop types to maximise yields.
• Crop Production Improvement: Adopting methods to boost overall crop output.
• Crop Protection Management: Taking steps to safeguard crops from damage and loss.

Crop Variety Improvement

Methods for Crop Variety Improvement

• Breeding for beneficial traits: Choosing varieties with qualities like disease resistance, fertiliser response, product quality, and high yields.
• Hybridisation: This involves crossing genetically different plants, which can be intervarietal (across different varieties), interspecific (between species of the same genus), or intergeneric (across different genera).
• Genetic modification: Adding specific genes to achieve desired traits in crops.

The factors for which variety improvement is done are:

• Higher yield: To increase the productivity of the crop per acre.
• Improved quality: Quality needs vary by crop. For example, baking quality is vital in wheat, protein quality is essential in pulses, oil quality is important in oilseeds, and preservation quality matters for fruits and vegetables.
• Biotic and abiotic resistance: Developing varieties that resist diseases, insects, nematodes, drought, salinity, waterlogging, heat, cold, and frost. Crop production can suffer due to biotic stresses (like diseases and insects) and abiotic stresses (like drought and salinity). Varieties that can withstand these stresses can enhance crop production.
• Change in maturity duration: Shorter crop duration from sowing to harvesting makes the variety more economical. This allows farmers to grow multiple crops in a year and reduces production costs. Uniform maturity simplifies harvesting and lowers losses during the process.
• Wider adaptability: Developing varieties that can adapt to various environmental conditions helps stabilise crop production. A single variety can then thrive in different climatic regions.
• Desirable agronomic characteristics: Traits like tallness and extensive branching are beneficial for fodder crops, while shorter plants are preferred in cereals to consume fewer nutrients. Thus, developing varieties with these traits boosts productivity.

Crop Production Management

• In India, as in many other agriculture-focused countries, farming varies from small to very large farms.
• Consequently, farmers have differing amounts of land, resources, and access to information and technology.
• Financial conditions significantly influence the farming practices and technologies that farmers can adopt.
• Cultivation methods and crop yield depend on factors like weather, soil quality, and water availability.
• Since weather conditions, such as drought or floods, can be unpredictable, varieties that grow well in various climatic situations are beneficial.
• Similarly, varieties that tolerate high soil salinity have also been developed.

Nutrient Management

Plant Nutrients

• Essential nutrients: Plants need nutrients from air, water, and soil for growth. Air provides carbon and oxygen, water supplies hydrogen, and soil provides the other thirteen nutrients.
• Macro-nutrients: These are nutrients required in large amounts, including carbon, oxygen, hydrogen, and others from the soil.
• Micro-nutrients: These are needed in smaller quantities and are also supplied by the soil.

A lack of these nutrients can negatively impact plant growth, reproduction, and disease resistance.

Deficiency of these nutrients affects reproduction, growth, and susceptibility to diseases in plants.

Manure

Manure contains large quantities of organic matter and also supplies small quantities of nutrients to the soil. Manure is prepared by the decomposition of animal excreta and plant waste. Manure helps enrich the soil with nutrients and organic matter and increases soil fertility.

Manure

Benefits of Manure

• Enriches soil: Manure adds organic matter and nutrients, enhancing soil fertility.
• Improves soil structure: The organic matter in manure helps soil hold water better in sandy soils and improves drainage in clay soils.
• Environmentally friendly: Using manure reduces the need for chemical fertilizers and recycles farm waste.

Types of Manure

       (i) Compostand vermicompost:

• Composting:This involves breaking down waste like animal dung and vegetable scraps to create nutrient-rich compost.
• Vermicomposting: In this method, earthworms are used to speed up decomposition, resulting in vermicompost.Vermicomposting
• (ii) Green manure:
  • Plants such as sun hemp or guar are grown before planting other crops. When these plants are turned into the soil, they enrich it with nitrogen and phosphorus.

Fertilizers

• Fertilizers are commercially manufactured nutrients that provide nitrogen, phosphorus, and potassium.
• They are essential for promoting healthy growth of leaves, branches, and flowers, leading to robust plants.
• Fertilizers significantly contribute to higher crop yields in intensive farming.Fertilizers

Benefits and Considerations of Fertilizers

• Boosts plant growth: Fertilizers deliver key nutrients like nitrogen, phosphorus, and potassium, fostering healthy growth.
• Increases yields: When used correctly, fertilizers can enhance crop productivity in high-cost farming.

Proper Application and Precautions

• While aiming for maximum crop yields, consider the quick benefits of fertilizers alongside the long-term advantages of manure for soil health.
• Fertilisers need to be applied carefully, focusing on the right amount and timing to ensure they are fully used by plants.

Organic farming is a method that minimises or eliminates the use of chemical fertilisers, herbicides, and pesticides. It maximises the use of organic manures, recycled farm waste such as straw and livestock dung, and employs natural agents like blue-green algae for creating biofertilisers. Additionally, neem leaves or turmeric can be used as natural pesticides during grain storage, promoting healthier farming systems.

Organic Farming

• Organic farming reduces or eliminates the use of chemicals like fertilizers, herbicides, and pesticides.
• Instead, it focuses on maximising the use of organic manures, recycled farm waste (like straw and livestock excreta), and bio-agents, such as cultures of blue-green algae for biofertilizers.
• Additionally, neem leaves or turmeric can serve as bio-pesticides for grain storage.
• Healthy cropping systems, including mixed cropping, inter-cropping, and crop rotation, are used to enhance control of insects, pests, and weeds while providing essential nutrients to crops.

Irrigation

Proper irrigationis very important for the success of crops. Most agriculture in India relies on rain, meaning the success of crops in many areas depends on timely monsoons and adequate rainfall throughout the growing season. Therefore, poor monsoons can lead to crop failure. Ensuring that crops receive water at the right times during their growing season can boost the expected yields of any crop.

Irrigation

Types of Irrigation Systems

• Wells: There are two types of wells: dug wells and tube wells. A dug well collects water from shallow water-bearing layers, while tube wells can reach deeper water sources. Pumps are used to lift water from these wells for irrigation.
• Canals: This is usually a large and complex irrigation system. Canals receive water from one or more reservoirs or rivers. The main canal splits into branch canals, which have further distributaries to irrigate fields.
• River lift system: In areas where canal flow is inconsistent due to insufficient reservoir release, this system is more effective. Water is taken directly from rivers to support irrigation in nearby areas.
• Tanks: These are small storage reservoirs that collect and store runoff from smaller catchment areas. New initiatives to increase available water for agriculture include rainwater harvesting and watershed management. This involves creating small check-dams, which help raise groundwater levels. The check-dams prevent rainwater from flowing away and reduce soil erosion.

Droughts occur due to a lack or irregular distribution of rain. Drought poses a risk to rain-fed farming areas, where farmers rely solely on rain for crop production. Light soils hold less water, and in such areas, crops are negatively affected by drought conditions.

Cropping Patterns

Cropping patterns refer to various methods of growing crops to achieve the best results. These methods include:

Types of Cropping Patterns

• Mixed cropping: Growing two or more crops at the same time on the same land, such as wheat with gram, wheat with mustard, or groundnut with sunflower. This method reduces the risk of disease and helps protect against crop failure.
• Inter-cropping: Planting two or more crops together in a specific pattern, like rows of soybean alternating with rows of maize, or finger millet (bajra) with cowpea (lobia). This ensures that each crop has different nutrient needs, optimising nutrient use and reducing pest and disease spread.
• Crop rotation: Growing different crops on the same land in a planned sequence. The choice of crops depends on moisture availability and irrigation. Proper crop rotation can allow for two or three successful harvests in a year.

Crop Protection Management

• Field crops face many threats from weeds, insects, and diseases. Managing these threats timely is crucial to avoid significant crop damage and losses.
• Weeds: Unwanted plants in the fields, such as Xanthium (gokhroo), Parthenium (gazar ghas), and Cyperus rotundus (motha). They compete for resources, reducing crop growth. Therefore, removing weeds early is essential for a good harvest.
• Insect pests: They harm plants in three main ways: by cutting roots, stems, and leaves; by sucking sap; and by boring into stems and fruits, all of which can lower crop health and yields.
• Diseases: Caused by pathogens like bacteria, fungi, and viruses, which can spread through the soil, water, and air, leading to reduced crop health.

Methods of Control

• Pesticides: Chemical solutions such as herbicides, insecticides, and fungicides are used to manage weeds, pests, and diseases, though excessive use may harm the environment.
• Mechanical removal: Physical methods, like manual weeding, can be used to control weed growth.
• Preventive measures:
  • Seed bed preparation: Properly preparing the seed bed and timely sowing of crops can help prevent weed growth.
  • Intercropping & crop rotation: Planting multiple crops together or rotating them can lessen the impact of pests and diseases.
  • Resistant varieties: Using crop varieties that resist pests and diseases.
  • Summer ploughing: Deep ploughing in summer to eliminate weeds and pests, reducing their effect on future crops.

Storage of Grains

Storage losses in agricultural products can be significant. The reasons for these losses are biotic—such as insects, rodents, fungi, mites, and bacteria—and abiotic factors like unsuitable moisture and temperature levels in storage. These factors lead to a decline in quality, weight loss, reduced germination, and discoloration of the produce, ultimately resulting in poor marketability.

Control Measures

Preventive Measures

• Preventive and control measures are implemented prior to storing grains.
• Thorough cleaning of the produce is essential.
• Proper drying should be done in both sunlight and shade.
• Fumigation with pest-control chemicals is necessary.
• Effective seedbed preparation, timely sowing of crops, intercropping, and crop rotation assist in controlling weeds.
• Utilising resistant varieties and summer ploughing can help eliminate weeds and pests.

Systematic Warehouse Management

• This is vital for minimising storage losses.
• The process involves organised treatment of grains and effective management of warehouses.

Animal Husbandry

• Animal husbandry is the scientific management of livestock, which includes activities such as feeding, breeding, and controlling diseases.
• This type of farming involves animals like cattle, goats, sheep, poultry, and fish.
• As the population grows and living standards improve, the demand for milk, eggs, and meat also increases.
• Moreover, there is a heightened awareness about the humane treatment of livestock, leading to new considerations in farming practices.
• Therefore, there is a need to enhance livestock production to meet these rising demands.

Cattle Farming

• Cattle farming serves two main purposes: producing milk and providing draught power for agricultural tasks like ploughing, watering, and transporting goods.
• In India, cattle are classified into two species: Bos indicus (cows) and Bos bubalis (buffaloes).
• Female animals that produce milk are referred to as milch animals, while those used for labour are known as draught animals.
• The amount of milk produced is influenced by the lactation period, which is the time after a calf is born that the mother produces milk.
• This production can be enhanced by extending the lactation period.
• Exotic breeds (like Jersey and Brown Swiss) are often chosen for their longer lactation periods, whereas local breeds (such as Red Sindhi and Sahiwal) are known for their strong disease resistance.
• Cross-breeding these types can result in animals that possess both desirable traits.Cattle Farming

Proper Care and Shelter

• Animals such as cows and buffaloes require clean shelter for their well-being and to ensure the production of clean milk. Regular grooming is necessary to remove dirt and loose hair. They should be housed in well-ventilated sheds that protect them from rain, heat, and cold. The floors of these shelters should be sloped to remain dry and facilitate cleaning.

Feeding Requirements

• Dairy animals have two types of food needs: 
  (a) maintenance requirement, which keeps them healthy, and 
  (b) milk-producing requirement, which is essential during lactation. 
• Animal feed consists of
  (a) roughage, which is high in fibre, and
  (b) concentrates, which are lower in fibre but rich in proteins and nutrients. 

Cattle require a balanced diet that provides all necessary nutrients in the right proportions. Certain feed additives containing micronutrients can also enhance the health and milk yield of dairy animals.

Diseases and Control

• Cattle can suffer from various diseases that may reduce milk production.
• A healthy animal typically eats regularly and maintains a normal posture.
• Cattle can be affected by both external and internal parasites.
• External parasites live on the skin and lead to skin problems, while internal parasites like worms can harm the stomach and intestines, and flukes can damage the liver.
• Infectious diseases can also arise from bacteria and viruses.
• Vaccinations are administered to livestock to protect against many significant viral and bacterial diseases.

Poultry Farming

Poultry farming is the practice of raising birds like chickens for their eggs and meat. Special poultry breeds are created for specific roles: layers produce eggs, while broilers are bred for meat. Cross-breeding between local Indian breeds, such as the Aseel, and foreign breeds like the Leghorn aims to create new varieties with desirable characteristics, which include:

• High numbers and quality of chicks;
• Dwarf broiler parents for commercial chick production;
• Ability to adapt to hot weather;
• Low maintenance needs;
• Smaller egg-laying birds that can thrive on cheaper, more fibrous diets made from agricultural by-products.

Egg and Broiler Production

Broiler chickens are specifically raised for meat and are sent to market when ready. Their diet is rich in protein and includes adequate fat. The poultry feed is also high in vitamins A and K to ensure optimal growth and efficient feed use. Careful management is essential to minimise mortality and maintain feather and meat quality.

Importance of Good Management Practices

Effective management practices are vital for successful poultry production. This includes:

• Keeping the housing at the right temperature;
• Ensuring cleanliness of the environment and feed;
• Preventing and managing diseases and pests.

Different Requirements for Broilers

Broilers have different housing, nutritional, and environmental needs compared to egg layers. Their specific diet is designed to support their growth requirements.

Disease Prevention and Control

Poultry can get sick from various causes, including:

• Viruses;
• Bacteria;
• Fungi;
• Parasites;
• Nutritional deficiencies.

Regular cleaning, sanitation, and disinfecting are essential to prevent diseases. Vaccination is crucial to protect against infectious diseases and reduce losses during outbreaks.

Interestingly, poultry in India is highly efficient at converting low-fibre food that is unsuitable for human consumption into nutritious animal protein.

Fish Production

• The main aim is that fish serves as an affordable source of protein in our meals.
• Fish production includes various species, such as true finned fish and shellfish like prawns and mollusks.
• Fish can be obtained in two ways: through natural resources, known as capture fishing, or through farming, referred to as culture fishery.
• Fish can live in either seawater or freshwater, including rivers and ponds, allowing for fishing in both marine and freshwater ecosystems.

Marine Fisheries

• India has a long coastline of 7500 km and is rich in deep-sea fish resources.
• Popular marine fish found in these waters include pomfret, mackerel, tuna, sardines, and Bombay duck.
• Marine fish are caught using various fishing nets from fishing boats.
• To improve fishing, modern tools like satellites and echo-sounders help locate large schools of fish, increasing the catch.

Aquaculture in Seawater

• Certain valuable marine fish are grown in seawater through a method called mariculture.
• Examples of farmed finned fish include mullets, bhetki, and pearl spots. Shellfish like prawns, mussels, and oysters are also cultivated.
• Seaweed is another product obtained from mariculture, and oysters are cultivated not only for their meat but also for pearl production.

Meeting the Increasing Demand

• As stocks of marine fish are depleted, the demand can only be met through culture fisheries, a practice known as mariculture.

Inland Fisheries

Inland Fisheries

• Freshwater resources consist of canals, ponds, reservoirs, and rivers.
• Brackish water areas, like estuaries and lagoons, are also important for fish.
• While fish are captured in these inland waters, most production comes from aquaculture.

Aquaculture in Freshwater Systems

• Fish can be grown in paddy fields, where they coexist with rice crops.
• Intensive fish farming takes place in composite fish culture systems that use both local and imported fish species.
• In composite fish culture, different fish species are chosen so they do not compete for food. For instance, Catlas feed at the surface, Rohus in the middle, while Mrigals and Common Carps feed at the bottom, and Grass Carps eat weeds. This mix allows for maximal use of food without competition.
• A challenge in composite fish culture is that many fish breed only during the monsoon. Even if fish seeds are collected from the wild, they may mix with other species. To solve this, methods have been developed to breed these fish in ponds using hormonal stimulation, ensuring a steady supply of pure fish seeds in the right amounts.

Fish Culture

• Fish culture can be combined with rice crops, where fish are grown in the water of paddy fields.
• Composite fish culture systems allow for more intensive fish farming.
• Many fish species in composite fish culture only breed during the monsoon.
• Multiple fish species are selected for a single fishpond, each having different food habits to utilise all available food.
• Surface feeders, middle-zone feeders, bottom feeders, and weed eaters are combined to optimise food utilisation and increase fish yield.
• A major problem in fish farming is the lack of availability of good-quality seed.
• Even if fish seed is collected from the wild, it can be mixed with that of other species as well.
• To overcome this problem, ways have now been worked out to breed these fish in ponds using hormonal stimulation.
• This has ensured the supply of pure fish seed in desired quantities.

Challenges in Fish Farming

• Many fish species in composite fish culture only breed during the monsoon.
• A major problem in fish farming is the lack of availability of good-quality seed.
• To overcome this problem, ways have now been worked out to breed these fish in ponds using hormonal stimulation.

Bee-Keeping

Bee-keeping for honey production is an agricultural enterprise since it requires low investments, making it an additional income-generating activity for farmers.

• Local bee varieties, such as Apis cerana indica (the Indian bee), A. dorsata (the rock bee), and A. florae (the little bee), are used alongside the Italian bee (A. mellifera) for commercial honey production.
• The Italian bees have high honey collection capacity, sting somewhat less, and stay in a given beehive for long periods.
• The quality of honey depends on pasturage, and bee farms or apiaries are established for commercial honey production.
• Honey production also provides wax, which is used in various medicinal preparations.

Factors Affecting Honey Quality

• The value and quality of honey depend on the availability of pasturage (flowers) for bees to collect nectar and pollen.
• The taste of honey is determined by the type of flowers available in the vicinity, in addition to a sufficient quantity of pasturage.