▁ne c rot ic ▁les ions ▁on ▁the ▁roots . ▁ ▁Sym pt oms ▁of ▁P . ▁pen etr ans ▁make ▁it ▁hard ▁to ▁distinguish ▁from ▁other ▁plant ▁path og ens ; ▁only ▁an ▁ass ay ▁of ▁soil ▁can ▁conclus ively ▁diagn ose ▁a ▁n emat ode ▁problem ▁in ▁the ▁field . ▁P . ▁pen etr ans ▁is ▁phys ically ▁very ▁similar ▁to ▁other ▁n emat ode ▁species , ▁but ▁is ▁character ized ▁by ▁its ▁highly ▁distinct ive ▁mouth pie ce . ▁P . ▁pen etr ans ▁uses ▁its ▁highly ▁modified ▁mouth ▁org ans ▁to ▁ru pt ure ▁the ▁outer ▁surface ▁of ▁sub ter rane an ▁plant ▁root ▁structures . ▁It ▁will ▁then ▁enter ▁into ▁the ▁root ▁interior ▁and ▁feed ▁on ▁the ▁plant ▁t issue ▁inside . ▁P . ▁pen etr ans ▁is ▁considered ▁to ▁be ▁a ▁c rop ▁par as ite ▁and ▁far mers ▁will ▁often ▁treat ▁their ▁soil ▁with ▁various ▁p estic ides ▁in ▁an ▁attempt ▁to ▁eliminate ▁the ▁damage ▁caused ▁by ▁an ▁inf est ation . ▁In ▁doing ▁this , ▁far mers ▁will ▁also ▁eliminate ▁many ▁of ▁the ▁benef icial ▁soil ▁fa una , ▁which ▁will ▁lead ▁to ▁an ▁overall ▁de grad ation ▁of ▁soil ▁quality ▁in ▁the ▁future . ▁Altern ative , ▁more ▁environment ally ▁sust ain able ▁methods ▁to ▁control ▁P . ▁pen etr ans ▁populations ▁may ▁be ▁possible ▁in ▁certain ▁regions . ▁ ▁Host s ▁and ▁sympt oms ▁ ▁Root ▁les ion ▁n emat ode ▁has ▁a ▁wide ▁host ▁range , ▁including ▁hosts ▁like ▁apple , ▁cher