Tomato rootstocks have been successfully used for eggplant production. However, the safety of herbicides registered in tomato has not been tested on grafted eggplant, which is a combination of tomato rootstock and eggplant scion. Greenhouse and field experiments were conducted to determine response of grafted eggplant on tomato rootstock to napropamide, metribuzin, halosulfuron, trifluralin, S-metolachlor, and fomesafen herbicides. In greenhouse experiments, herbicide treatments included pretransplant S-metolachlor (400 and 800 g ai ha⁻¹), pre- or posttransplant metribuzin (140 and 280 g ai ha⁻¹), and posttransplant halosulfuron (18 and 36 g ai ha⁻¹). In field experiments, herbicide treatments included pretransplant fomesafen (280 and 420 g ai ha⁻¹), halosulfuron (39 and 52 g ha⁻¹), metribuzin (280 and 550 g ha⁻¹), napropamide (1,120 and 2,240 g ai ha⁻¹), S-metolachlor (800 and 1,060 g ha⁻¹), and trifluralin (560 and 840 g ai ha⁻¹). The eggplant cultivar ‘Santana' was used as the scion and nongrafted control, and two hybrid tomatoes ‘RST-04−106-T' and ‘Maxifort' were used as rootstocks for grafted plants. In both greenhouse and field experiments, there was no difference between grafted and nongrafted eggplant in terms of injury caused by herbicides. Metribuzin posttransplant at 140 and 280 g ha⁻¹ caused 94 and 100% injury to grafted and nongrafted eggplant 4 wk after treatment. In field experiments, pretransplant fomesafen, napropamide, S-metolachlor, and trifluralin caused less than 10% injury and no yield reduction in grafted and nongrafted eggplant. However, metribuzin caused injury and yield reduction in both grafted and nongrafted eggplant. Metribuzin at 550 g ha⁻¹ caused 60 and 81% plant stand loss in 2013 and 2014, respectively. Halosulfuron reduced yield 24% in both grafted and nongrafted eggplant compared to nontreated control in 2013 but did not reduce yield in 2014. The pretransplant S-metolachlor, napropamide, fomesafen, and trifluralin are safe to use on eggplant grafted onto tomato rootstock, and will be a valuable addition to the toolkit of eggplant growers.

Nomenclature: Fomesafen; halosulfuron; metribuzin; napropamide; S-metolachlor; trifluralin; eggplant, Solanum melongena L.; tomato, Solanum lycopersicum L.

Los patrones de tomate han sido exitosamente usados para la producción de berenjena. Sin embargo, la seguridad de herbicidas registrados para tomate no ha sido evaluada en berenjena injertada, la cual es una combinación de patrón de tomate e injerto de berenjena. Experimentos de invernadero y de campo fueron realizados para determinar la respuesta de berenjena injertada sobre un patrón de tomate a los herbicidas napropamide, metribuzin, halosulfuron, trifluralin, S-metolachlor, y fomesafen. En los experimentos de invernadero, los tratamientos de herbicidas incluyeron S-metolachlor (400 y 800 g ai ha⁻¹) en pretrasplante, metribuzin (140 y 280 g ai ha⁻¹) en pre y postrasplante, y halosulfuron (18 y 36 g ai ha⁻¹) en postrasplante. En los experimentos de campo, los tratamientos de herbicidas incluyeron fomesafen (280 y 420 g ai ha⁻¹), halosulfuron (39 y 52 g ha⁻¹), metribuzin (280 y 550 g ha⁻¹), napropamide (1,120 y 2,240 g ai ha⁻¹), S-metolachlor (800 y 1,600 g ha⁻¹) y trifluralin (560 y 840 g ai ha⁻¹), todos en postrasplante. El cultivar de berenjena 'Santana' fue usado como injerto y como testigo sin injertar, y dos híbridos de tomate 'RST-04-106-T' y 'Maxifort' fueron usados como patrones para las plantas injertadas. Tanto en los experimentos de invernadero como en los de campo, no hubo diferencias entre las berenjenas injertadas y no injerta