Question

How can we make allopolyploid species, and why can it be useful?

What is the difference between the mutation and recombination, in terms of the effect on population variation?

Answer 1

Synthetic allopolyploids can be made by following procedure

1) Identification of desirable species A and species B

2) Pollination and fertilization of them to obtain the rescue embryo

3) We may use use test-tube fertilization of protoplast fusion if there is reproductive barrier

4) These rescued embryos are regenerated or transplanted to form allodiploids ( which contain 2n chromosomes)

5) Generation of 2n gametes which are also called reduced gametes by application of anti-microtubule agents.

6) The unreduced gametes can be fertilized to normal gametes to make Allopolyploids. Generally back-crossing is preferred with desirable parental species.

Allopolyploids are advantageous because of their ubiquitous occurrence in nature. Gene dosage, gene redundancy, Heterosis, and reproductive system significance are some of their advantages.. Allopolyploids have upper-hand in breaking down hybrid incompatibility, moreover they also form unreduced gametes and also undergo chromosome doubling during evolution or under selection pressure.

Many important crops such as wheat, cotton, and canola, are allopolyploids and display improved agricultural traits in comparison to their diploid progenitors. Allopolyploidy has played a significant role indentifying domestic of crops and their further selection for desirable products.

Difference between mutation and recombination

Mutation	Recombination
The permanent and heritable changes in the nucleotide sequence of the genes or chromosomes are referred as mutation	During recombination, New nucleotide rearrangements are produced by exchange of DNA strands.
Types of mutations are as follows, 1) Point mutation 2) Frameshift mutation 3) Chromosomal mutation	Types of recombination 1) Homologous recombination 2) Site-specific recombination 3) Transposition
The mutation are mainly caused by error-prone DNA replication	The recombination occurs during the meiotic division or plasmid to genome recombination in E.Coli
Caused by mutagens e.g chemicals, radiation	Occur naturally
Small changes to genome, introduction of new alleles and genetic variance within small population	Large and significant change to genome , leads to evolutionally changes within species, traits
Minor contribution for evolution	Major and significant contribution for evolution and survival of the fittest