Strategies for Enhancement in Food ProductionNEET Zoology · Class 12 · NCERT Chapter 9

You can expect 1 question from this chapter in NEET 2027. The most reliable scoring areas are: the difference between inbreeding and outbreeding, the meaning and purpose of MOET, the scientific name of the honeybee used in apiculture (Apis indica), the steps of plant breeding, biofortification examples (Atlas 66 wheat, lysine and tryptophan-rich maize), and the concept of single cell protein. Tissue culture terms (totipotency, callus, somaclone) also appear.

Inbreeding depression is the reduced fertility, reduced productivity and increased disease susceptibility that appears after several generations of mating closely related animals (inbreeding). It happens because inbreeding increases the chance that two copies of a harmful recessive gene are inherited together. It is managed by outbreeding: selecting superior bulls from one breed and mating them with superior cows of another breed (cross-breeding), or by selecting unrelated animals of the same breed (out-crossing) to restore genetic variability and productive capacity.

MOET stands for Multiple Ovulation Embryo Transfer Technology. A superior female (cow, sheep, etc.) is given hormones that cause her ovaries to release many eggs at once (super-ovulation, typically 6 to 8 eggs). She is mated with a superior bull (or artificially inseminated), and the fertilised embryos are flushed out and transferred into surrogate mothers. This lets you get many offspring from one genetically superior female per year, instead of just one. It is important because it multiplies the genetic contribution of elite animals and speeds up the improvement of livestock breeds.

There are five main steps in order. (1) Collection of variability: gather germplasm (seeds, plants) from many sources, including wild relatives. (2) Evaluation and selection of parents: screen the germplasm for the desired traits and select the best individuals as parents. (3) Cross hybridisation among selected parents: cross the selected parents to combine their good traits in one plant. (4) Selection and testing of superior recombinants: from the progeny, identify plants that have the desired combination of traits and are better than both parents. (5) Testing, release and commercialisation: test the new variety in different environments; if it performs well it is released as a new cultivar.

Biofortification is plant breeding aimed at improving the nutritional quality of a crop: more vitamins, more minerals or more protein in the seeds or fruit. Key NEET examples are: (1) Maize hybrids that have twice the level of amino acids lysine and tryptophan compared to normal maize. (2) Atlas 66, a wheat variety with a much higher protein content than ordinary wheat. (3) Iron and calcium-rich spinach and carrots (less commonly asked). The goal is to fight nutritional deficiency diseases, especially in populations that depend heavily on a single crop.

Single cell protein is protein-rich dried biomass of microorganisms (algae, fungi, bacteria) grown on cheap waste materials. The microorganism is grown in large fermenters and the dried cells are used as a protein supplement for humans or animal feed. Key NEET examples: Spirulina (a cyanobacterium, also called blue-green alga), grown on waste water from potato processing; and Methylophilus methylotrophus, a bacterium that uses methanol as carbon source and can produce 25 tonnes of protein per acre per year. SCP is important because it can replace conventional protein sources like fish meal and soybean.

Totipotency is the ability of a single plant cell (or a small group of cells) to grow into a whole new plant. This is the basis of plant tissue culture. A small piece of tissue called an explant is taken from the plant and placed on a sterile nutrient medium with plant growth hormones. The explant divides to form an undifferentiated mass called a callus. The callus is then shifted to a different medium (with different hormone ratios) and shoots and roots form. This process produces exact genetic copies of the parent plant called somaclones, and the technique is called micropropagation. Somatic hybridisation (protoplast fusion) is another tissue culture technique: cell walls are removed from two different plant cells and the naked protoplasts are fused to make a hybrid. The classic example is pomato (potato + tomato).