In biotechnology, propagation is mainly by

In biotechnology, propagation refers to the process of reproducing or multiplying a particular organism or tissue. There are different methods of propagation, but in general, the goal is to create new individuals that are genetically identical to the original. Out of the given options, the method of propagation mainly depends on the type of organism and the desired outcome. However, in general, cell culture is the most commonly used method of propagation in biotechnology. Cell culture involves growing cells in a controlled environment, usually in a laboratory setting. This method is particularly useful for growing large numbers of cells, which can then be used for various purposes, such as studying cellular functions or developing drugs. In addition, cell culture can also be used to propagate whole organisms, such as plants, by growing their cells in vitro and then inducing them to differentiate into a new plant. Grafting and aerial layering are methods commonly used for propagating plants, while binary fission is a method of reproduction used by some microorganisms. However, these methods are not as widely used in biotechnology as cell culture, which is a highly versatile and reliable technique for propagating cells and organisms.