Find below the important notes for the chapter, Strategies for Enhancement in Food production, as per NEET Biology syllabus. This is helpful for aspirants of NEET and other exams during last-minute revision. Important notes for NEET Biology- Strategies for Enhancement in Food production covers all the important topics and concepts useful for the exam. Check BYJU’S for the full set of important notes and study material for NEET Biology and solve the NEET Biology MCQs to check your understanding of the subject.
|Name of the NEET sub-section||Topic||Notes helpful for|
|Biology||Strategies for Enhancement in Food production||NEET exams|
Strategies for Enhancement in Food production – Important Points, Summary, Revision, Highlights
Strategies for Enhancement in Food production
Food is necessary for the development and survival of all the organisms. To cater to the need of the increasing population, it is necessary to increase food production. Plant breeding, animal husbandry and modern technologies like tissue culture, genetic engineering, embryo transfer have increased the yield by many folds.
It is a practice of raising and breeding livestock (buffaloes, cattle, sheep, cow, etc.). It also includes poultry farming and fisheries.
Dairy farm management and poultry farm management is required to select good breed having high yielding potential and disease-resistant varieties.
Animal Breeding and Types
A breed is a group of animals of the same species, that are related in descent and have common features and appearance.
There are two types of breeding, Inbreeding and Outbreeding
It refers to breeding between male and female and of the same breed for 4 to 6 generations. For this purpose superior males and superior females are selected and mated.
Inbreeding promotes homozygosity and is required for evolving pure lines or true breeding species as the case in Mendel’s experiment.
Inbreeding removes undesirable genes and accumulates superior genes.
Inbreeding depression results from continuous inbreeding. Here, productivity, as well as fertility decreases, which can be restored by mating with unrelated superior animals.
It refers to mating unrelated animals. This can be of three types:
- Out-crossing: It is mating of the same breed, which do not have a common ancestor for few generations. This helps in overcoming inbreeding depression.
- Cross-breeding: It helps in combining superior traits of two breeds. For this purpose superior males of one breed are mated with superior females of another breed.
Hisardale- Result of cross-breeding of Marino rams (males) and Bikaneri ewes (female), a new breed of sheep is developed in Punjab.
- Interspecific hybridization: Breeding between two different and related species.
Mule- A hybrid of a male donkey and a female horse.
Controlled breeding experiments are done to overcome several problems related to normal mating. Artificial insemination is used for control breeding. Semen may be used immediately or frozen and can be transported to use later on.
Multiple Ovulation Embryo Transfer Technology (MOET) increases successful hybridisation chances.
In this method, the cow is given hormones similar to FSH (Follicle-stimulating hormone) to induce follicular maturation. This results in the production of more (6-8) eggs compared to one in a normal cycle. Mating or artificial insemination is done with the semen of an elite bull and the fertilised eggs (at the stage of 8-32 cells) are transferred to surrogate mothers.
It is the maintenance of a beehive of honey bees for the production of honey. Honey is a nutrient-rich compound extracted from beehives. Beeswax is used in various industries to prepare cosmetics, polishes, etc. Apis indica is the most common species of honey bees.
Also Read: MCQs on Apiculture
Blue revolution is related to an increase in the production of fishes and other aquatic animals.
Aquaculture is breeding and rearing aquatic flora (fish, molluscs, crustaceans) and fauna (aquatic plants and algae) for commercial use. Extensive aquaculture is done in oceans, rivers or lakes, whereas intensive aquaculture is done in ponds and tanks.
Pisciculture is fish farming to get edible fish and fish products. In polyculture, different fishes are cultured together. In monoculture, different species are cultured separately.
Plant breeding is manipulative breeding of plants to get desired traits in plant species such as superior quality, high yield and disease resistance.
The Green Revolution refers to increased production of food to meet the population requirement. The green revolution in India was founded by M. S. Swaminathan. Modern methods and technologies are used for this purpose, e.g. use of fertilizers, pesticides, high yielding seeds, irrigation facilities, etc.
High yield varieties of wheat and rice have greatly contributed to the increase in food grain production.
Plant breeding is done to increase yield, improve quality, tolerance to environmental stress, resistance to various pathogens and pests.
Government and various companies run plant breeding programmes worldwide. The steps to yield a new genetic variety of plant are:
- Collection of variability- It is the collection of all the variety of a given crop. All the different alleles for all the genes of a plant are collected. It is known as germplasm collection.
- Evaluation and selection of parents- The germplasm is evaluated for the desired trait.
- Cross hybridisation- Two desired characters are combined, e.g. disease resistance plant is cross-bred with a plant having high protein content.
- Selection and testing of superior recombinants- Hybrids having desired characters are selected and self-pollinated for various generations to get homozygosity. This ensures that characters do not segregate in the next generation.
- The commercialisation of new cultivars- Proper quality check is done for yield and other qualities like disease resistance. For this purpose, the crop is grown in a research field under controlled conditions.
Evaluation is followed by testing in farmer’s fields all around the country for three consecutive seasons.
Some of the high yielding varieties of hybrid Indian crops
Wheat: Norman E Borlaug developed semi-dwarf varieties of wheat in Mexico. It increased the production of wheat from 11 million to 75 million tonnes.
Sonalika and Kalyan Sona are high-yielding and disease-resistant wheat varieties grown in India.
Rice: Semi-dwarf varieties of rice were derived from IR-8 (developed in the Philippines) and Taichung Native-1 (Taiwan).
Jaya and Ratna are semi-dwarf rice varieties developed in India
Sugar cane: Two different sugarcane species, Saccharum barberi (grown in north India) and sugar-rich Saccharum officinarum (grown in South India and have thick stems) were cross-bred successfully to get sugarcane, high in yield, sugar content and thick stem, that can be grown in North India too.
Millets: High yielding and resistant to water stress variety of jowar, maize and bajra are developed in India.
Plant Breeding for Disease Resistance
Approximately 20-30% of crops are lost due to various diseases caused by bacteria, viruses and fungi.
Disease resistant varieties are developed by the conventional method (hybridisation and selection) or by mutation method. Genetic engineering and selection among somaclonal variants are also used to get disease-resistant variety.
Some of the examples of disease-resistant varieties, that are developed by the conventional method of hybridisation and selection are:
Mutation Breeding: Mutation causes a change in the gene sequence. Mutation can be induced artificially to get the desired trait, which was not present earlier.
Examples: The new variety of Mung beans have been developed by mutation, that is resistant to powdery mildew disease and yellow mosaic virus.
It is important to have diseases resistant quality along with high yielding capacity. To get this combination, disease-resistant genes are transferred to high yielding varieties by sexual hybridisation. A new variety of bhindi, that is resistant to the yellow mosaic virus was developed and called Parbhani Kranti. The disease resistance quality was transferred from a wild species.
Plant Breeding for Pest Resistance
There is large scale destruction of crops due to insects and pests. The process of development of pest-resistant varieties is similar to disease resistance.
Some of the examples of pest-resistant varieties developed and being used commercially are:
Plant Breeding for Improved Food Quality
Other than disease resistance, pest resistance and high yield, it is also important for crops to have greater nutrient value to eradicate nutrient deficiency diseases.
We can improve public health by producing nutrient-rich crops, which will have healthier fat, higher protein, vitamins and minerals content.
Biofortification: The process of breeding nutrient-rich crops is known as biofortification. Crops with improved nutritional value have improved quality and content of protein, oil, vitamins, micronutrient and mineral content. IARI (Indian Agricultural Research Institute), New Delhi has released many varieties of vegetables rich in vitamins and minerals.
Some examples of biofortified crops developed are:
|Hybrid maize (developed in 2000)||Twice the amino acids lysine and tryptophan|
|Wheat (Atlas-66)||High Protein content|
|Rice||Iron-rich (5 times more)|
|Carrots, pumpkin, spinach||Vitamin A enriched|
|Mustard, bitter gourd, tomato, bathua||Vitamin C enriched|
|Spinach and bathua||Iron and Calcium enriched|
|French beans, broad beans, lablab beans and garden peas||Protein-enriched|
Single Cell Protein (SCP): Single-cell protein is one of the sources of protein and can meet the requirement for the nutrition of ever-increasing human and animal population.
To get SCP, microbes are grown on an industrial scale. Blue-green algae like Spirulina are a good source of nutrients and can be grown easily on wastewater from sewage, potato processing plants, animal manure and straw molasses.
The bacteria Methylophilus methylotrophus can produce 25 tonnes of protein due to its high growth rate and biomass production. Large scale production of edible mushrooms is a growing industry.
Tissue culture is the process of developing the whole plant form a part of the plant.
The capacity of an explant (part of the plant) or a cell to regenerate the whole plant is known as totipotency.
Micropropagation is a method of producing thousands of plants using tissue culture. The medium should be rich in nutrients. It should have a carbon source (sucrose), growth regulators (auxins, cytokinins), vitamins, inorganic salts and amino acids.
Somaclones: Each of the plants developed by tissue culture is known as somaclones and they are identical to the parent plant.
Many food crops like tomato, apple, banana, etc. have been produced on a commercial scale using tissue culture methods.
The tissue culture method is also useful in getting rid of disease infections. The apical and axillary meristem is free from a viral infection, which can be removed and grown in vitro to get a healthy plant. Meristems of banana, potato and sugarcane have been cultured successfully.
Somatic Hybridisation: It is the process of fusing naked protoplasts (protoplast with the plasma membrane, after digesting cell wall) of cells of two different varieties of plants having desirable traits. The plants grown by this method are known as somatic hybrids.
Pomato has been developed using potato and tomato but did not contain the desirable combination of traits to be used commercially.
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