Evaluación de nematicidas para el combate de Meloidogyne incognita en dos cultivares de Apium graveolens.

The effects of aldicarb, carbofitran, ethoprop, phenantiphos and fensulfothion, at rates of 4, 5, 7, 5 and 4 kg al lha, respectively, on the yield and other characteristics of celery, cv. 5204 and Dwarf, were evaluated on an alluvial soil infested with a low initial population density of Meloidogyne incognita at the Ujarreis Valley, Costa Rica. Aldicarb, phenatniphos and carbofuran significantly increased the yield of 'Dwarf' as compared to the control. There were no significant effects of the chemicals on the plant height and appearance on both cultivars, but they significantly reduced the root-knot index caused by M.. incognita, except fensulfothion on "5204" and ethoprop on "Dwarf". The root-knot index was significantly higher on the "5204" than on the "Dwarf" cultivar. Population densities of free living nematodes and M. incognita larvae were low in soil 44 days after trasplanting and increased a little at harvest time, but without reaching the same densities present before nematicides application.