Evaluation of the resistance of Vitis rotundifolia cultivars to brazilian ground pearl (Hemiptera: Margarodidae) in southern Brazil - DOI: 10.4025/actasciagron.v32i2.3151

Abstract

Brazilian ground pearl Eurhizococcus brasiliensis (Hempel in Wile) (Hemiptera: Margarodidae) is one of the main grape pests in southern Brazil. The resistance of Vitis rotundifolia cultivars (Bountiful, Chief, Creek, Dixie, Magnolia, Magoon, Noble, Regale, Roanoke, Sumith and Topsail) to Brazilian ground pearl was evaluated by comparison with 101-14 (Vitis riparia x Vitis rupestris) rootstock. The experiment was conducted in a naturally infested field, by measuring pest infestation on roots, dry weight of plants (leaves + roots) and mortality during three years. V. rotundifolia cultivars showed a reduced infestation by the pest, a higher vigor and lower mortality when compared to 101-14 rootstock. All 101-14 plants were killed by the pest after the second year in the field. The cultivars Bountiful, Chief, Magoon, Magnolia and Regale had low pest infestation, showing antixenosis or antibiosis resistance. The Dixie cultivar showed a higher pest infestation; however, this was associated with high plant vigor, suggesting the existence of tolerance. The results show that V. rotundifolia cultivars Bountiful, Chief, Magoon, Magnolia and Regale showed a low infestation by E. brasiliensis and can be alternatives for direct fruit production or pest resistance source in plant breeding programs