- Although mutations are often recessive, they can potentially be dominant.
- In general, mutations are bad for the organism.
- Mutations are arbitrary.
- Mutations frequently occur.
- Pleiotrophy is a typical feature of induced mutations and is frequently the result of mutations in nearby genes.
Mutagens
Mutagens are substances that are used to cause mutations. The many mutagens can be categorised as follows:
Physical mutagens
- Ionizing radiations
- Particulate radiations – α-rays, fast neutron, thermal neutrons.
- Non-particulate radiations – X-rays, γ-rays.
- Non ionizing radiation – Ultraviolet radiation.
Chemical mutagens
- Alkylating agents – Sulphur mustard, mustard gas, EMS (Ethyl methane sulphonate), Ethylene Imine (EI)
- Acridine dyes- acriflavin, proflavin, acridine orange, acridine yellow,ethedium bromide.
- Base analogues – 5-bromouracil, 5-Chlorouracil.
- Others – Nitric acid, hydroxyl amine.
Achievements
- Mango – Rosica from Peruvian variety Rosadodelca
- Papaya- Pusa Nanha from local type
- Grape-Marvel Seedless from Delight
- Banana- High gate from Gros Michel, Motta Poovan from Poovan
- Orange-Washington Navel
- Grapefruits – Marsh and Thompson
