Effects of Nonfumigant Nematicides Applied Through Low-Pressure Drip Irrigation on Control of Meloidogyne incognita on Tomatoes. Sahag Garabedian, Postdoctorate Research Associate, Department of Nematology, University of California, Riverside 92521. S. D. Van Gundy, Professor, Department of Nematology, University of California, Riverside 92521. Plant Dis. 69:138-140. Accepted for publication 27 July 1984. Copyright 1985 The American Phytopathological Society. DOI: 10.1094/PD-69-138.

The efficacy of two experimental nematicides, aldoxycarb and carbosulfan, was compared with that of carbofuran and oxamyl for control of Meloidogyne incognita on tomatoes. Chemicals were placed in PVC injectors through a low-pressure drip-irrigation system at rates from 0.37 to 3.37 kg a.i./ha as single or multiple applications. Single and multiple applications of all four chemicals proved effective in reducing root gall ratings at harvest. Chemicals lost their effectiveness between the second and third week after application. When chemicals were applied at 1.68 kg a.i./ha every 2 wk (total of 5.04 kg a.i./ha) or at 0.37 kg a.i./ha every 3 or 6 days (total of 2.22 kg a.i./ha), significant reductions in root gall ratings were observed, with substantial increases in tomato yield.