PLANT-PARASITIC NEMATODES IN WHITE CLOVER AND SOIL FROM WHITE CLOVER PASTURES IN AUSTRALIA

Seventeen sites, including locations in all the major white clover gro wing regions of Australia, were surveyed for the presence of plant par asitic nematodes in autumn and spring 1993. Trifolium repens L. cvv. H aifa and Irrigation, plus 1 other cultivar, were sampled at each site and nematodes extracted from roots, stems and soil. Thirteen genera of plant parasitic nematodes were detected. The clover cyst nematode, He terodera trifolii, and root knot nematodes, Meloidogyne spp., were eac h recorded at over 75% of the sites. The most common genera of plant p arasitic nematodes detected were Tylenchus, which was present at all s ites, and Pratylenchus (root lesion nematode), which was present at al l but 1 site. Other plant parasitic nematode genera found included Dit ylenchus, Helicotylenchus and Paratylenchus. The widespread presence o f nematodes in white clover pastures, and the high populations at some sites, suggest that they may be economically important to the Austral ian dairy industry.