Nematode Losses During Sieving from Two Soil Types


  • R. McSorley
  • J. L. Parrado


Criconemella onoensis, Extraction Efficiency, Helicotylenchus dihystera, Methodology, Meloidogyne incognita, Population Assessment, Quantitative Nematology, Quinisulcius acutus, Rotylenchulus reniformis, Tylenchorhynchus martini


Estimates of losses at each stage of a multistep sieving procedure were obtained for nematodes infesting Rockdale fine sandy loam and Perrine marl soils from southern Florida. The steps examined in the sieving procedure ranged from preparation of the soil subsample for extraction to concentration of a sieved subsample for centrifugation. Losses in the early stages of the sieving process (suspension of a soil subsample in water, screening through a coarse sieve) were much greater than losses in the latter stages (passing through a 38-m sieve, rinsing sieves, decanting). Estimates of maximum extraction efficiency through all of the sieving steps were 62.2% for Criconemella onoensis, 67.6% for Rotylenchulus reniformis, and 71.4% for Helicotylenchus dihystera on Rockdale soil; and 88.0% for C. onoensis and 75.8% for R. reniformis on Perrine marl soil. Experiments varying methodology at each step provided means for optimizing procedures at each step in the sieving process.