5 A J 
Alterations In Palatability to Nematodes 
A number of species of nematodes feed on tobacco roots (18). Of 
the species that occur in Wisconsin, the meadow nematode ( Praty- 
lenchus sp.) can be damaging when tobacco is planted after sod. 
This ectoparasitic nematode does not maintain itself well on 
tobacco, however, and is not an important pathogen on a crop 
continuously cultivated in the same field. In monitoring nematode 
populations, roots and rhizosphere soil will be collected, the 
nematodes screened, counted, and identification made. Any 
effect of the experimental tobacco on nematode populations 
would not be significant beyond the tobacco test plot, due to the 
relative immobility of the nematodes. Such an effect would not 
be significant subsequently in the absence o^ tobacco because the 
population would decline in the absence of the selective host: The 
root knot nematode is not a factor in Wisconsin tobacco 
production, but its possible presence in the experimental tobacco 
will be monitored at intervals during the growing season. Roots 
will be dug and examined for the presence of nematode galls. 
5AJj Alterations in Susceptibility to Fungal Diseases 
A number of fungus diseases are important in the cultivation of 
tobacco. There is no reason to believe that the genetic changes 
introduced into the tobacco in the test plot should effect 
susceptibility to fungal diseases. Any changes should be confined 
to the test plot. 
Environmental Assessment 
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