Ability of weeds to host the root lesion nematodes Pratylenchus neglectus and P. thornei - II. Broad-leaf weeds

Twenty dicotyledonous weed species from nine families were assessed for susceptibility to Pratylenchus neglectus (Rensch) Filipjev Schuurmans & Stekhoven and P. thornei Sher & Allen. The weeds tested are common in crops, pastures and fallows in southern Australia. Weeds were grown at 20 degreesC and individual plants inoculated with 2000 nematodes. Based on comparison of the reproductive factor (final population/initial population, or Pf/Pi) with the cereal controls, wheat cv. Machete (susceptible to P. neglectus and P. thornei) and triticale cv. Abacus (moderately resistant to P. neglectus and moderately susceptible to P. thornei), weeds were classified as non-hosts, poor hosts or good hosts. Heliotropium europaeum L. was a poor host of P. thornei (Pf/Pi = 1.55). Six species, Malva parviflora L., Rumex crispus L., Emex australis Steinh., Tribulis terrestris L., Brassica tournefortii Gouan, and Raphanus raphanistrum L. (Pf/Pi = 1.22-2.75), were good hosts of P. neglectus. Susceptibility was not related to plant family, root type, root texture or life span of the plant.