Washing Soil for Collection of Nematodes



 
  • Add 100cm3 soil into a 1 liter graduated cylinder. 
  • Add tap water to a volume of 1 liter. 
  • Cover cylinder with parafilm, invert to mix, and let settle for 60 sec. 
  • Decant over 25 mesh screen over 325 mesh screen (use a slow twirling motion so as not to disturb the soil pellet). 
  • Spray water over 25 mesh screen to extract any needle nematodes, Longidorus spp., nematodes are collected over 325 mesh screen. 
  • Wash nematodes from 325 mesh screen into a 150 ml beaker using water. 
  • Pour beaker contents into 50 ml round bottom centrifuge tubes. 
  • Centrifuge tubes at 400xg for 5 min. 
  • Decant supernatant from tubes. 
  • Add sucrose solution (454 g sucrose / liter water) to centrifuge tubes and mix. 
  • Centrifuge tubes at 400xg for 1 min. 
  • Decant tubes over 325 mesh screen. 
  • Rinse sucrose solution off screen using tap water from underneath the screen. 
  • Using tap water in a water bottle, rinse nematodes from screen into a 50 ml beaker (using less than 20 ml water). 

  • Cover beaker with parafilm and store at 4C until nematode isolation (samples can be stored this way for several weeks).