Reproduction is one of the vital and fundamental properties of living organisms. Every living being maintains continuity of its own kind by producing new individuals. Hence, reproduction is a process of perennation from generation to generation. This also helps maintaining the number of individuals of a particular species.
Plants reproduce generally, by three methods: Vegetative, asexual and sexual. In vegetative method of propagation, no specialized reproductive units are formed. The plant parts or its remnants (leaves, branches or roots) are here, capable of growing into a new individual, under suitable conditions. Among the angiosperms, vegetative reproduction can be induced. It is also inherent among many plants since their cells are tot potent.
In the asexual methods of reproduction, specialized reproductive structures develop which may later, convert it into new individual. This method of reproduction along with vegetative one is predominantly seen among the lower cryptogams. The asexual reproductive units are called zoospores, aplanospores, conidia etc.
The sexual method of reproduction naturally occurs among all kinds of plants. The specialized reproductive units are called gametes. In case of angiosperms these gametes (male or female) are borne in the flowers. The gametes bear half the number of chromosomes of the parent plant.
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The gametes fuse to form zygotes. The process is called fertilization. This restores the original number of chromosomes of the plant. Since asexual reproduction is characteristically shown by cryptogams already described in the vol.1 of this book, methods of vegetative and sexual reproduction of angiosperms are discussed in the following.