(a) The shift from grain to meat diets creates more demands for cereals. Why?
(b) A 250 kg cow produces 200 g of protein per day but 250 g of Methylophillus methylotrophus can produce 25 tonnes of protein. Name this emerging area of research. Explain its benefits.
(a) The shift from grain to meat diets creates more demand for cereals as it takes $3-10 \mathrm{~kg}$ of grain to produce 1 kg of meat by animal farming.
(b) This research is related to single cell protein.
Microbes are being grown on an industrial scale as a source of good protein. Microbes like Spirulina can be grown easily on materials like wastewater from potato processing plants (containing starch), straw, molasses, animal manure and even sewage, to produce large quantities and can serve as food rich in protein, minerals, fats, carbohydrate and vitamins.
Such utilisation also reduces the environmental pollution.
What are the advantages of tissue culture methods over conventional method of plant breeding in crop improvement programmes?
As traditional (conventional) breeding methods failed to keep pace with demand and to sufficiently provide fast and efficient systems for crop improvement, another technology called tissue culture developed.
The advantages of tissue culture over conventional breeding are as follows
(i) It can be used to produce large number of plantlets within a short period by micropropagation.
(ii) All cells in the culture are derived from a single explant by mitotic division, therefore all have the similar genotype and constitute a clone.
(iii) Tolerance to stress can be obtained by providing pollutants, toxins, salts, etc., in culture medium in increasing dosage. The surviving healthy cells are selected for raising resistant plants.
(iv) Virus free plantlets can be obtained by meristem culture.
(v) Embryos which do not survive inside seeds can be grown by tissue culture to form new plants.
'Modern methods of breeding animals and plants can alleviate the global food shortage'. Comment on the statement and give suitable examples.
With ever increasing population of the world, enhancement of food production is a major necessity. Modern biological principles as applied to animal husbandry and plant breeding have a major role in our efforts to increase food production. These modern techniques include embryo transfer technology and tissue culture techniques.
Multiple Ovulation Embryo Transfer Technology (MOET) is a programme for herd improvement in animals like cattle, sheep, rabbits, buffaloes, mares, etc.
High milk-yielding breeds of female are bred with high quality meat-yielding (meat with less lipid) bulls to increase herd size. It ensures good quality of progeny. It is also economic and time saving process to obtain the desirable progeny.
The procedure for MOET is as follows
(i) A cow is administered hormones with FSH-like activity to induce follicular maturation and super-ovulation.
(ii) The cow produces 6-8 eggs instead of one egg produced normally.
(iii) It is now, either mated with an elite bull or artificial insemination is carried out.
(iv) When the fertilised eggs attain 8-32 cells stage, they are non-surgically removed and transferred to a surrogate mother.
(v) The genetic mother can now be again super ovulated.
Modern methods in plant breeding involves following
(i) Tissue culture is an in vitro technique of regeneration of a whole plant from any part of a plant (explant) by growing it on culture medium under aseptic conditions.
(ii) Biofortification is the method for developing crops with higher levels of vitamins, minerals, proteins and healthier fats to improve public health.
(iii) Single cell protein is an alternative protein source for animal and human nutrition from certain beneficial microorganisms like Spirulina.
Does apiculture offer multiple advantages to farmers? List its advantages if it is located near a place of commercial flower cultivation.
Yes, apiculture offers many advantages to farmers such as
(i) Honey produced by honeybees is a food of high nutritive value.
(ii) It is used in the indigenous system of medicine.
(iii) Honeybee also produces beeswax, which is used in the preparation of cosmetics and polishes of various kinds.
If apiculture is done near a place of commercial flower cultivation it offers several advantages. Bees are the pollinators of many crop species such as sunflower, Brassica, apple and pear. Keeping beehives in crop fields during flowering period
(i) Increases pollination efficiency.
(ii) Improves the yield which is beneficial both from the point of view of crop yield and honey yield.
(a) Mutations are beneficial for plant breeding. Taking an example, justify the statement.
(b) Discuss briefly the technology that made us self-sufficient in food production.
(a) It is possible to induce mutations artificially in plants through use of chemicals or radiations (like gamma radiations), and then selecting and using those plants that have the desirable character as a source in breeding.
This process is called mutation breeding. In mung bean, resistance to yellow mosaic virus and powdery mildew was induced by mutations.
(b) Traditional farming can only yield a limited biomass, as food for humans and animals. Better management practices and increase in agricultural land area can increase yield, but only to a limited extent. Plant breeding as a technology has helped increase production to avery large extent.
Plant breeding is the purposeful manipulation of plant species in order to create desired plant types that are better suited for cultivation, give better yields and are disease resistant.
This technology has given support to green revolution, which was responsible for not merely meeting the national requirements in food production, but also helped us to export it.