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Genetic abnormalities
 

A number of genetic abnormalities occur on tobacco. With genetic abnormalities usually only a few plants are affected and they appear to be a real curiosity. Generally, the colour and leaf shape are quite characteristic of the particular abnormality and thus do not cause confusion.

 
These foliar chimeras result in  a yellow or white partial discoloration of the lamina of different degrees. The plants show irregular spots of various forms from yellow-green to creamy-white that give to the leaves a beautiful mottled or mosaic appearance (figures 1 and 2). Very severely affected plants may be totally white (albinos) (figure 3) and die. These discolorations are a result of an abnormal development of chloroplasts in the leaf tissues.
 
Only the affected plants demonstrate this genetic disorder which is never transmitted to neighboring plants. However, it can be transferred to the offspring, if the affected  plant is used in a cross. Thus a cross using this plant should be avoided, unless one wants to create "ornamental" tobacco. In general, one can eliminate the affected plants as soon as they are observed.
 
Other genetic disorders induce morphological changes in tobacco, they are presented in the fact sheets of Abnormal leaf size and shape.

Last change : 02/01/13
  • Author :
  • D Blancard (INRAe)
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Figure 1
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Figure 2
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Figure 3