DISTRIBUTION, HOST STATUS AND POTENTIAL SOURCES OF RESISTANCE TO VITTATIDERA ZEAPHILA [DISTRIBUCIÓN, SUSCEPTIBILIDAD Y FUENTES POTENCIALES DE RESISTENCIA A VITTATIDERA ZEAPHILA]

Donald, P.A., R. Heinz, E. Bernard, D. Hershman, D. Hensley, S. Flint-Garcia, R. Joost. 2012. Distribution, host status and potential sources of resistance to Vittatidera zeaphila. Nematropica 42:91-95. Vittatidera zeaphila was described from stunted Zea mays (corn) roots collected in northwestern Tennessee (Obion County) in 2006. Similar cyst specimens had previously been collected in 1978 from Lauderdale County, TN, on Eleusine indica (goosegrass). Comparison of the 1978 specimens deposited in the USDA Nematology Collection at Beltsville, MD, and the 2006 specimens verified that they were identical. The purpose of this research was to determine the distribution of this nematode, determine the host range and determine if there was resistance which could be incorporated into commercial corn hybrids in the event the nematode was a threat to Midwest corn production. This nematode is known only from the 1978 site in Lauderdale County, TN and the two findings in Obion County, Tennessee and a field in Hickman County, Kentucky from this study. Zea mays and E. indica were the only plants supporting increase of this nematode and were good hosts, with Rf values of 6 or more. Nonhosts included common dicotyledous plants that are known hosts of cyst nematodes, a range of native grasses, and teosinte. Preliminary data on potential sources of resistance to V. zeaphila suggest that resistance is not a dominant trait and that there is a potential role of the cytoplasm in conferring resistance. Donald, P.A., R. Heinz, E. Bernard, D. Hershman, D. Hensley, S. Flint-Garcia, R. Joost. 2012. Distribucion, susceptibilidad y fuentes potenciales de resistencia a Vittatidera zeaphila. Nematropica 42:91-95. En 2006 se describio Vittatidera zeaphila asociado a raices de maiz (Zea mays) con pobre crecimiento en el noroeste de Tennessee (Condado de Obion). Especimenes similares de este quiste se habian colectado previamente en 1978 en el condado de Lauderdale, Tennessee, en el pasto Eleusine indica. La comparacion de los especimenes de 1978 depositados en la Coleccion de Nematologia del laboratorio del Departamento de Agricultura (USDA) en Beltsville, Maryland con los especimenes del 2006 mostro que eran identicos. El objetivo de esta investigacion es determinar la distribucion de este nematodo y su rango de hospedantes y deteminar si existe resistencia que pueda utilizarse en hibridos comerciales de maiz en caso de que este nematode se convirtiera en amenaza para la produccion de maiz en Estados Unidos. Esta especie solo se ha registrado en 1978 en Lauderdale, los dos hallazgos en Obion County, en Tennessee y en un campo en el condado de Hickman en Kentucky que reportamos en este estudio. Las dos plantas que demostraron ser buenas hospedantes son Zea mays y E. indica, con factores reproductivos (Rf) de 6 o mas. Se encontro que plantas dicotiledoneas comunmente hospedantes de otros nematodos quiste, varios pastos nativos y teosinte no son hospedantes de este nematodo. Datos preliminares sobre fuentes potenciales de resistencia a V. zeaphila sugieren que la resistencia no es un caracter dominante y que es posible que el citoplasma juegue algun papel en la resistencia.