Field Evaluation of Tomato spotted wilt virus Resistance in Transgenic Peanut (Arachis hypogaea).

Spotted wilt, caused by Tomato spotted wilt virus (TSWV), is a devastating disease of many crops including peanut (Arachis hypogaea). Because the virus has a broad host range and is spread by ubiquitous thrips, disease management by traditional means is difficult. Developing new peanut cultivars with resistance to TSWV presents a significant challenge since existing genetic resistance in peanut germ plasm is limited. A genetic engineering approach appears to have great potential for resistance enhancement to TSWV. Transgenic peanut progenies that expressed the nucleocapsid protein of TSWV were subjected to natural infection of the virus under field conditions during the growing seasons of 1999 and 2000 in Tifton, GA, and in three locations (Tifton, GA, Marianna, FL, and Headland, AL) in 2001. Significantly lower incidence of spotted wilt was observed for the transgenic progeny in comparison to the nontransgenic checks in the field (in multiple years and locations) as well as during challenge inoculation under controlled environmental conditions. This transgenic event could potentially be used in a traditional breeding program to enhance host resistance.