How is biotechnology useful for increasing food production in agriculture.

There are three options for increasing food production. They are as follow : $(i)$ Agrochemical based agriculture. $(ii)$ Organic agriculture and $(iii)$ Genetically engineered crop based agriculture.

The Green Revolution succeeded in tripling the food supply but yet it was not enough to feed the growing human population.

Increased yields have partly been due to the use of improved crop varieties but mainly due to the use of better management practices and use of agrochemicals. (Pesticides and fertilizers).

However for farmers in the developing world agrochemicals are often too expensive. Genetically modified crops are useful to obtain better yield of crops.

Plants, bacteria, fungi and animals whose genes have been altered by manipulation are called Genetically Modified Organisms ($GMO$).

$GM$ plants have been useful in many ways.

Genetic modification has : $(i)$ made crops more tolerant to abiotic stresses (cold, drought, salt, heat) $(ii)$ reduced reliance on chemical pesticides. (pest resistant crops) $(iii)$ helped to reduce post harvest losses. $(iv)$ increased efficiency of mineral usage by plants (this prevents early exhaustion of fertility of soil). $(v)$ enhanced nutritional value of food e.g., golden rice i.e. Vitamin $'A'$ enriched rice. In addition to these uses. $GM$ has been used to create tailor made plants to supply alternative resources to industries, in the form of starches, fuels and pharmaceuticals.

Some of the applications of biotechnology are the production of pest resistant plants which could decrease the amount of pesticide used.

$Bt$ toxin is produced by a bacterium called Bacillus, thuringiensis.

- $Bt$ toxin gene has been cloned from the bacteria and been expressed in plants to provide resistance to insects without the need for insecticides in effect created a bio-pesticide. Examples are $Bt$ cotton, rice, tomato, potato and soyabean etc.