Response of Cotton to Infection by Hoplolaimus columbus.

Three field experiments were established in 1987 to determine the reaction of five cotton cultivars to infection by Hoplolaimus columbus and the efficacy of selected nematicides against this nematode. At two sites in Calhoun County, South Carolina, early season plant growth and subsequent yields were greater in plots treated with aldicarb, fenamiphos, and 1,3-dichloropropene. Hoplolaimus columbus suppressed yields approximately 10% at site 1 and 25% at site 2; however, greater yield suppression at site 2 may have been influenced by low levels of Meloidogyne incognita. At one site in Barnwell County, South Carolina, nematicide treatments did not increase plant growth or yield. At sites 1 and 2 where yield losses occurred, no differences in infection rate or yield among untreated cultivars were observed, nor was any nematicide more effective than another in preventing yield losses.