What is the significance of apomixis?
What is the significance of apomixis?
The correct option is B It preserves the characteristics of hybrids in future generations
Apomictic seeds are a result of the phenomenon called apomixis. Apomixis is a method of asexual reproduction where seeds are formed without fusion of two different types of gametes. Since, it leads to the formation of new plants from the seeds of a single parent, the offspring produced are identical to one another.
Hence apomixis does not induce variations in the progeny.
Hybrids are cultivated these days on a large scale as they have superior traits. But the traits of hybrid plants are lost in successive generations as the hybrid plants produce seeds through sexual reproduction which involves meiosis and fertilisation. To retain the characters of hybrids, the seeds have to be produced every year which is very expensive.
But by the mechanism of apomixis, seeds are produced without fertilisation (sexual reproduction) from the single parent and hence there is no segregation of characters in the progeny.
Hence the characteristics of hybrids are preserved in future generations by apomixis and also this method of producing seeds is not expensive.
In contrast to sexual seed formation, apomixis can occur by various mechanisms that share three common developmental components:
(i) a bypass of meiosis during embryo sac formation (apomeiosis)
(ii) development of an embryo independent of fertilization (a process known as parthenogenesis)
(iii) formation of viable endosperm either via fertilisation-independent means or following fertilisation with a sperm cell. So although it bypasses meiosis during embryo development, in some plants fertilisation may be needed to induce or start it.
Apomictic seeds are a result of the phenomenon called apomixis. Apomixis is a method of asexual reproduction where seeds are formed without fusion of two different types of gametes. Since, it leads to the formation of new plants from the seeds of a single parent, the offspring produced are identical to one another.
Hence apomixis does not induce variations in the progeny.
Hybrids are cultivated these days on a large scale as they have superior traits. But the traits of hybrid plants are lost in successive generations as the hybrid plants produce seeds through sexual reproduction which involves meiosis and fertilisation. To retain the characters of hybrids, the seeds have to be produced every year which is very expensive.
But by the mechanism of apomixis, seeds are produced without fertilisation (sexual reproduction) from the single parent and hence there is no segregation of characters in the progeny.
Hence the characteristics of hybrids are preserved in future generations by apomixis and also this method of producing seeds is not expensive.
In contrast to sexual seed formation, apomixis can occur by various mechanisms that share three common developmental components:
(i) a bypass of meiosis during embryo sac formation (apomeiosis)
(ii) development of an embryo independent of fertilization (a process known as parthenogenesis)
(iii) formation of viable endosperm either via fertilisation-independent means or following fertilisation with a sperm cell. So although it bypasses meiosis during embryo development, in some plants fertilisation may be needed to induce or start it.
