Technical Abstract: Incidence and severity of Huanglongbing (HLB) disease were assessed in April, 2010 among eight citrus cultivars representing diverse scion types growing in commercial groves in Florida’s Indian River region, an area with high incidence of HLB. Twenty trees of each cultivar were rated for visual HLB symptoms and leaves were collected for quantification of Candidatus Liberibacter asiaticus (CLas), presumptive causal agent of HLB. There was a strong correlation between HLB incidence and CLas titer, whether on a grove basis or a cultivar basis. Although incidence and severity of HLB varied considerably among the groves, differences among the scions were apparent, even when analyses excluded differences between groves. ‘Temple’ tangor showed the most consistently low incidence of HLB symptoms and CLas titer; in contrast, ‘Murcott’ tangor and ‘Minneola’ tangelo had the highest incidence of HLB symptoms and highest CLas titer. These results suggest useful resistance to huanglongbing may be found in conventional scion cultivars and further work is needed to assess this potential and its commercial value.