Could recent yield plateauing in cotton be related to reniform nematodes? That's a question, nematologists are pondering. But there's one thing they're sure about. The reniform nematode is becoming a bigger and bigger problem in the South.

Plant breeders and nematologists are working together on developing long-term methods of control, such as reniform-resistant cotton varieties, Meanwhile, short-term control methods include rotation with non-host plants, fumigation and in-furrow treatments. Be sure to know your nematode before choosing a rotation partner.

DuPont is suggesting a short-term method of control for both the reniform and root knot nematode, the use of its carbamate Vydate C-LV at pinhead square, following an at planting application of Temik.

The Temik/Vydate treatment may not significantly reduce extremely high populations of nematodes in fields, according to Mark Lindsey, insecticide product manager for DuPont. No short-term solutions do. But it could help, he says.

University and DuPont tests from 1994-1999 indicate that Vydate C-LV increased yields by more than 20 percent over just the use of Temik alone. That gain was typically 25-100 pounds of lint per acre.

The company, and some consultants, recommend the pinhead square timing because that's usually when cotton producers make an application for plant bugs. By using Vydate for plant bug control, the producer will gain nematicidal activity too.

Vydate is systemic and will translocate to roots, where nematodes attack. Vydate also controls or suppresses boll weevil, tarnished plant bug, fleahopper and onion/tobacco thrips.