NEET Biology Strategies for Enhancement in Food Production

The chapter strategies for enhancement in food production is of high importance from the NEET 2022 point of view, and students must be well versed with the basics. These notes contain the synopsis of the chapter and can be really helpful for a quick go through of the chapter. 

Here, we’ll be discussing all the important concepts of the chapter, such as animal husbandry, plant breeding, single cell proteins and tissue culture and some other crucial concepts.  

Important Topics of Strategies for Enhancement of Food Production

• Animal Husbandry

• Animal Breeding

• Bee-keeping

• Single Cell Protein

• Tissue Culture

• Plant Breeding

Important Concepts of the Chapter

Animal Husbandry

All creatures require food for their development and survival. The major necessity for enhancement of food production is to meet the demands of an ever-increasing population. Plant breeding, animal husbandry, and modern technologies such as tissue culture, genetic engineering, and embryo transfer have dramatically enhanced yield.

Animal Breeding and Types

A breed is a collection of animals from the same species that are related in descent and have similar characteristics and appearance. Inbreeding and outbreeding are two types of breeding.

Difference Between Inbreeding and Outbreeding

Bee-keeping (Apiculture)

It is the care and maintenance of a honey bee hive for the production of honey. Honey is a nutrient-dense substance derived from beehives. Beeswax is utilised in a variety of sectors to make cosmetics, polishes, and other products. Apis indica is the most prevalent honey bee species.

Fisheries

• Blue Revolution - The growth in the production of fish and other aquatic creatures is linked to the Blue Revolution.

• Aquaculture - It is the practice of commercially breeding and rearing aquatic flora (fish, molluscs, crustaceans) and fauna (aquatic plants and algae). Intensive aquaculture takes place in ponds and tanks, whereas extensive aquaculture takes place in seas, rivers, or lakes.

• Pisciculture - is the growing of fish for the purpose of producing edible fish and fish products. Different fishes are cultivated together in polyculture. Different species are cultured separately in monoculture.

Plant Breeding

Plant breeding is the process of selectively breeding plants to achieve desired characteristics in them, such as higher quality, high production, and disease resistance.

Green Revolution

Enhanced food production to fulfil population demands is referred to as the Green Revolution. M. S. Swaminathan was the driving force behind India's green revolution. Fertilizers, insecticides, high yielding seeds, irrigation infrastructure, and other modern procedures and technology are employed for this purpose.

Wheat and rice varieties with high yields have made a significant contribution to the expansion in food grain output.

Plant breeding is done to improve production, quality, tolerance to environmental stress, and pest and pathogen resistance. Plant breeding programmes are run by the government and private companies all around the world. The following are the steps involved in creating a new plant genetic variety:

Main Steps Required for Developing New Varieties:

1. Collection of variability - It is the collection of all the different varieties of a particular crop. All of a plant's alleles for all of its genes are gathered. Germplasm collection is the term for it.

2. Germplasm evaluation and parent selection - The germplasm is tested for the desired characteristic and parents are chosen based on the results.

3. Cross hybridisation - is when two desirable characteristics are united, such as disease resistance and high protein content.

4. Selection and testing of superior recombinants - Hybrids with desired traits are chosen and self-pollinated over several generations in order to achieve homozygosity. This prevents character segregation in the next generation.

5. New cultivator testing, release, and commercialization - It entails a thorough quality inspection for productivity and other characteristics such as disease resistance. The crop is cultivated in a controlled environment in a research area for this purpose.

Some High Yielding Varieties of Hybrid Indian Crops

Plant Breeding for Disease Resistance

Mutation Breeding

A mutation is an abrupt, stable, and heritable alteration in an organism's gene expression. As a result, a new personality emerges that is not present among parents. 

The mutation is a term used to describe experimentally generated mutations that are used to improve crops. Mutation breeding refers to the agents that are employed to cause mutation in crops for the purpose of agricultural improvement. Mutagens are chemicals that are used to cause mutations. Physical agents such as x-rays, ultraviolet rays, and gamma rays, as well as various compounds such as HNO₂, base analogues, and acridine dyes.

Biofortification

Biofortification is the process of breeding nutrient-dense crops. Crops with higher nutritional value have higher protein, oil, vitamin, micronutrient, and mineral content, as well as higher quality. The Indian Agricultural Research Institute (IARI) in New Delhi has published a number of vitamin and mineral-rich vegetable cultivars.

Examples of Biofortified Crops Developed

SCPs (Single Cell Proteins)

Single cell proteins are the cells of microorganisms such as bacteria, yeasts, and filamentous algae that have been processed in various ways and utilised as food. Excess nucleic acid is removed throughout the processing. Whey, sulphite waste liquor, hydrocarbon waste from the petroleum sector, waste water including scratch from potato processing factories, straw, molasses, and animal manure are some of the basic materials used in single cell protein production.

Tissue Culture

Tissue culture is the method of growing an entire plant from a single cell. Totipotency is the ability of an explant (a piece of a plant) or a cell to regenerate the entire plant.

Micropropagation is a tissue culture-based method for growing thousands of plants. The medium should be nutrient-dense. A carbon source (sucrose), growth regulators (auxins, cytokinins), vitamins, inorganic salts, and amino acids should all be present.

Somaclones: Each plant grown by tissue culture is referred to as somaclon and is identical to the parent plant.

Many food crops, such as tomato, apple, and banana, have been commercially cultivated utilizing tissue culture technologies.

Types of Culture

• Callus culture and suspension culture

• Meristem culture

• Embryo culture

• Anther culture

• protoplast culture

Somatic Hybridisation

Somatic Hybridisation can be described as the procedure of fusing naked protoplasts (protoplasts with the plasma membrane after the cell wall has been digested) of cells from two different species of plants that have desirable features. Somatic hybrids are the plants grown in this manner.

Pomato was created by combining potato and tomato, however, it lacked the desired combination of features to be commercially viable.

Solved Examples from the Chapter

1. Autopolyploidy can be induced artificially by

1. Chloroform

2. Colchicine

3. Chloroquine

4. Colchine

Ans: b. Colchicine

Autopolyploidy is a kind of polyploidy in which there are more than two copies of homologous chromosomes in the chromosomal complement. Since microtubules are involved in chromosomal segregation, colchicine causes polyploidy by blocking chromosome segregation during meiosis, resulting in half of the gametes (sex cells) having double the amount of chromosomes.

Key point to remember- Colchicine causes polyploidy by blocking chromosome segregation during meiosis.

2. A cybrid is hybrid carrying (35)

1. Genomes and cytoplasm of two different plants

2. Cytoplasms of two different plants

3. Cytoplasms of two different plants but genome of one plant

4. Genomes of two different plants

Ans: c. Cytoplasms of two different plants but the genome of one plant

A cybrid is a cell or plant hybrid that has the genome of one species but the cytoplasm of the other. A cytoplasmic hybrid is also known as a cybrid. The process of creating a cybrid is termed cybridization. 

Key point to remember- Nuclear material from one organism is introduced into a cell that has had its nucleus removed to create a cytoplasmic hybrid eukaryotic cell.

3. Main objective of production of herbicide resistant GM crops is to

1. Encourage eco-friendly herbicides

2. Reduce herbicide accumulation in food articles for safety of health

3. Eliminate weeds from fields without the use of manual labour

4. Eliminate weeds from fields without the use of herbicides  

Ans: b. Reduce herbicide accumulation in food articles for safety of health

Weeds compete with crops for light, water, and nutrients, reducing agricultural yields and affecting crop quality. Herbicides will be used to get rid of weeds (weed killer). Maize, cotton, soybeans, tobacco, and other crops have developed herbicide tolerance. The major goal is to limit herbicide accumulation in food products in order to protect people's health.

Key point to remember- Herbicides are primarily used to get rid of weeds.

Solved Problems of Previous Year Question from the Chapter

1. By which method was a new breed ‘Hisardale’ of sheep formed by using Bikaneri ewes and Marino rams?

1. Cross breeding

2. Inbreeding

3. Outcrossing

4. Mutational breeding

Ans: a. Cross breeding

Cross-breeding is the technique of breeding two individuals from different species. In Punjab, the "Hisardale" sheep breed was created by combining Bikaneri ewes with Marino rams.

Key point to remember- Crossbreeding is also called ‘’designer crossbreeding".

2. Select the incorrect statement.

1. Inbreeding is essential to evolve purelines in any animal.

2. Inbreeding selects harmful recessive genes that reduce fertility and productivity.

3. Inbreeding helps in the accumulation of superior genes and the elimination of undesirable genes.

4. Inbreeding increases homozygosity.  

Ans: b. Inbreeding selects harmful recessive genes that reduce fertility and productivity.

Inbreeding makes deleterious recessive genes visible, which are then selected out. It also aids in the accumulation of superior genes while removing undesirable genes. As a result, the selection is made at each phase to maximise the productivity of the inbred population. Inbreeding is known to impair fertility and even productivity in animals.

Key point to remember- The development of offspring from mating or breeding individuals that are genetically related is referred to as inbreeding.

3. Artificial selection to obtain cows yielding higher milk output represents;

1. Stabilizing selection as it stabilizes the character in the population

2. Directional as it pushes the mean of the character in one direction

3. Disruptive as it splits the population into two one yielding higher output and the other lower output

4. Stabilizing followed by disruptive as it stabilizes the population to produce higher yielding cows

Ans: b. Directional as it pushes the mean of the character in one direction

Artificial selection is a procedure which can be used to obtain cows yielding higher milk output that will result in the shift of the mean of the character to one side. This is a directional change.

Further, the organism that carries the mean value of the trait is opted out in the stabilising selection. The process of selecting extremes is termed as a disruptive selection.

Key point to remember- Artificial selection is a directional change.

Practice Questions

1. Semi-dwarf wheat was developed by

1. Swaminathan

2. N.E. Borlaug

3. Ramdhan

4. None of these

Ans: b. N.E. Borlaug

Semi Dwarf wheat was created by agronomic Norman Borlaug. This semi-dwarf wheat was found to be exceptionally successful in the United States, where it was planted on around 22% of the wheat cultivated acreage. Sonalika is a wheat cultivar that was introduced to India as a semi dwarf.

2. In livestock breeding experiments, which of the following stages is transferred to surrogate mothers? 

1. Unfertilized eggs

2. Fertilized eggs

3. 8 to 32 celled embryo

4. Frozen semen

Ans: c. 8 to 32 celled embryo

In MOET, a cow is given hormones with FSH-like action to induce follicular maturation and superovulation, resulting in the production of 6-8 eggs per cycle rather than the typical one. The animal would either be artificially inseminated or mated with an outstanding bull. The fertilised eggs are collected non-surgically and delivered to surrogate mothers at the 8–32 cell stage. The next round of hyperovulation is possible with the genetic mother.

3. In maize, hybrid vigour is exploited by

1. Inducing mutations

2. Bombarding the protoplast with DNA

3. Crossing of two inbred parental lines

4. Harvesting seeds from the most productive plants

Ans: c. Crossing of two inbred parental lines

Heterosis, also known as hybrid vigour, refers to a hybrid's greater vigour (size, strength, and so on) than its parents.

It is always superior to either of its parents because it is a hybrid. Height, viability, a higher output of fruits and seeds, increased tolerance to environmental conditions, resistance to diseases, pests, and better seed germination are all examples of heterosis in plants.

In many crops, such as maize, heterosis has been commercially exploited by crossing two inbred parental lines. After several generations, the vigour is lost.

Conclusion

The Strategies for Enhancement in Food Production NCERT PDF covers all the crucial concepts and further at the end, certain sample questions have been added. These sample questions give clarity over the types of questions that can be asked in the NEET examination. Moreover, previous year questions and practice questions have also been added, which a student can practice once they are done with the chapter.