What is embryo rescue? When is this method followed?

Hint:Plant breeding can be defined as manipulation of a plant species to produce desired phenotypes and genotypes. Embryo rescue is a technique that is used in modern plant breeding.

Complete answer:
Embryo rescue is the type of in vitro fertilization method. This method is used for the development of the plants from the cells or the parts of the plants which are not able to survive and produce viable plants. This technique is useful in the development of many interspecific and intergeneric food and ornamental plant crop hybrids.
It is the most commonly used method for embryo rescue. Generally, in this method seeds from controlled pollination plants are collected prior to the expected embryo abortion occurrence. Then, isolation and excision of embryos occur which are then placed directly onto the culture medium for the generation of fertile plants.
This method is followed when there is a formation of the weak embryo which is not able to nourish the seed and so there is no production of the new plant. So, this method is performed to nurture the embryo to produce plants.

Note: It is to be noted that besides embryo culture, ovule and ovary culture, which are more suitable for small-seeded species or very young embryos, are also utilized for embryo rescue.