Which part of the tobaco plant is infected by meloidogyne incognita ?why?and also give some pictures ?

ROOT IS VULNERABLE TO INFECT BECOZ THEY ARE IN UNDERGROUND WITH HOT CLIMATES AND SHORT WINTER... ROOTNOT NEMATODES AND PARASITES ARE THE GENUS MELODIGYNE...

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meloidogyna icognitia , is a root infecting nematode of the tobacco plant ,
so, it mainly affect the roots of the tobacco plant . 
so, this infection is very common in the case of tobbaco plant and it will reduce almost 15- 60 percent of the yield of tobbaco plant ., 
the plant infected having the symptoms of nutrient efficiency , plant become yellow and willted and stunted growth of plant . 
the giant cell present in the icognitia block the surrounding xylem vessels , it also induces the multiplication of cortical cell , which result in the formation of charecteristics galls . 
HOPE IT CLEARS 
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