Cotton Incorporated

Nematology Research

Plant-parasitic nematodes cost cotton growers more, in chemical control expenses, direct damage through root feeding, and indirect losses through increased susceptibility to wilts, than any other class of plant diseases.

The root-knot nematode (Meloidogyne incognita) is found throughout the Cotton Belt; and the reniform nematode (Rotylenchulus reniformis), an invading tropical pest, has spread throughout the Southeast, and more recently spread northward into the alluvial soils of the mid-South. No existing control measures completely eliminate losses due to cotton nematodes.

Crop rotation with non-host crops can provide one-year of nematode suppression, but effective, disease-suppressing crop rotation is infrequently practiced due to the lower potential income that may be expected from many of the candidate rotation crops.

Chemical control is expensive, only partially effective, and highly toxic. In conjunction with our Cotton Variety Improvement Initiative, Cotton Incorporated has concluded that the most cost-effective way to control nematodes is to develop host plant resistance against nematodes in cotton. Although genetic resistance against certain nematodes is available in public germplasm, the resistance sources are not being used by commercial breeders, because evaluation of the resistance requires counting nematodes, a labor-intensive procedure that is too expensive.

Cotton Incorporated is investing in development of advanced, resistant germplasm and identification of genetic markers for nematode resistance that will be published and be made broadly available to all private and public breeders.