INDUCED MUTATION BY GAMMA RAY

ROLE OF GAMMA RAY IN CROP IMPROVEMENT

ARTFICIAL MUTATION                     

By:- Mukesh Kr. Bhelloria

In fact electromagnetic radiation widely used in the crop improvement program. Gamma ray is the most important electromagnetic radiation because of its high penetration capacity. I am trying to perform such artificial mutation for betterment in the field of plant breeding.

                                                                                                               For every activity in an organism certain gene is responsible. For Ex:-  toxicity in Lathyrus sativus is a lethal effect which causes loss at economic level. We have to identify the lethal gene which is responsible for toxicity in such plants. We can use molecular marker for identification of such gene. After identification we have to apply gamma ray on targeted gene and remove the lethal gene. This is a critical work so, we should take care during this experiment. There is only 15-20% chances of +ve result.

Gamma sources are used to irradiate a wide range of plant materials, like seeds, whole plants, plant parts, flowers, anthers, pollen grains and single cell cultures or protoplasts. Radiations have been used successfully to induce useful mutations for plant breeding. The lower doses/ concentrations of the mutagenic treatments could enhance the biochemical components, which are used for improved economic characters.

Gamma radiation can induce useful as well as harmful effects on crops so there is need to predict the most beneficial dose for improvement of specific traits of crop plants.

I presume you mean radiation-caused genetic mutations within the DNA molecule. 

Radiation is only one means of causing mutations. Others are caused by chemicals, heavy metals binding to DNA, and simple errors in copying DNA during cell divisions. DNA controls assembly of proteins and other molecules. If the DNA is altered, structures of proteins or other molecules are altered, and they usually do not work properly -- the vast majority of time, in fact. In very rare cases, the change creates molecules or alters structures so that they work better, perhaps even take on a new function. Most of the time, the cell with the mutation fails to function properly and it dies. If DNA repair functions fail to work, the cell can become cancerous. Might this be a good reason for people to avoid x-rays and other forms of radiation?If DNA in one cell of a multicellular organism has a lethal mutation, that cell dies, but in a tree or human, the loss of a cell or a few usually does not mean much. Why?If the mutation takes place in a germ cell (a cell that gives rise to eggs or sperm) that mutation could be passed on to descendents , if the new organism-to-be is not killed outright by its DNA that does not function properly. Evolution tends to weed out mutations that are deleterious. Evolution tends to preserve the rare mutations that confer a competitive advantage. There are so many we see with obvious mutations, characteristics that no one has seen before? This might indicate to we how rare beneficial genetic mutations are.





Experimental work/Lab work:-     

Requirements:-                       1. Source of gamma ray- Radium                      2.  Molecular marker                     3.  Reactor                     4. Rn                     5. Certain chemicals

Activity:-             Take a sample of cell protoplasm of the cell for gene identification. Identify the gene on which we wish to perform activity and mark with selectable marker. Apply gamma ray carefully to produce mutation.