Abstract
The effects of fallow or Tagetes erecta and Avena strigosa planting on the population density of Pratylenchus penetrans were studied in the field in Tokachi, Hokkaido, Japan. Planting of A. strigosa for 60 days or T. erecta for 100 days strongly suppressed the growth of P penetrans. Planting of T. erecta for 100 days, as well as weed-controlled fallow for three years, was found to be the most effective way to control P. penetrans. Planting of T. erecta for 60 days or fallow in summer did not sufficiently reduce the growth of P. penetrans. Weed-contaminated fallow increased the growth of P. penetrans, as most weeds in the test field are good hosts of P. penetrans.
