Pratylenchus spp. 

Brown root rot of tobacco

 
The Pratylenchus spp. are much less harmful to tobacco than Meloidogyne spp. They are spread worldwide and affect more than 500 plant species. They are reported on tobacco in all producing countries, but the damage varies from one country to another. Vietnamese cultures seem significantly affected by these nematodes. They are moderately or occasionally harmful for example in Canada, Chile, China, Pakistan, Germany and Italy.
 
In France, a few cases have been reported in recent years on tobacco. Given the frequency of outbreaks caused by T. basicola (Chalara elegans) on the roots of tobacco and symptoms this pathogen produces, it is possible that there have been confusions in diagnosis and that the losses by Pratylenchus spp. be underestimated. Two species, Pratylenchus crenatus (Loof, 1960) and Pratylenchus penetrans (Coober, 1917), have been observed. It should be noted that in some countries, Pratylenchus spp. promote the development of Chalara elegans. We do not know if this is the case in France.
 
Other species of Pratylenchus attack tobacco, including for instance Pratylenchus Brachyura (Godfrey 1929), Pratylenchus Scribners (Steiner 1943), Pratylenchus pratensis (de Man 1880), Pratylenchus neglectus (Rensch 1924).