It was studied the effect of Xylella fastidiosa infection, causal agent of Citrus Variegated Chlorosis (CVC), on the xylem sap ingestion rate of citrus plants by two sharpshooters species (Hemiptera: Cicadellidae). Seedlings of sweet orange Pera and Valencia (Citrus sinensis) were used and infected by X. fastidiosa, strain 9a5c, obtained by mechanical inoculation. The insects used in the experiments were collected in the field, one from Cicadellini Tribe (Dilobopterus costalimai) and another from Proconiini Tribe (Oncometopia facialis). The xylem sap ingestion rate by O. facialis was quantified in seedling twigs, and by D. costalimai in leaves and twigs, by means of evaluation of the liquid volume (honeydew) excreted by time unity. The consumption by O. facialis sharpshooter in diseased plants was inferior to healthy plants. In the diseased Pera variety the consumption was lower, not permitting a xylem sap quantification. In healthy Pera and healthy and diseased Valencia, O. facialis showed expressive rate of consumption, with high feeding during the day. In the healthy plants of both varieties, the consumption by D. costalimai sharpshooter was higher than in CVC diseased plants. Comparing both varieties, the rate was higher in the Valencia variety, and concerning parts of the plant, leaves and twigs, the ingestion rate was higher in the twigs of both varieties, with higher consumption during the day.
Cicadellinae; Citrus Variegated Chlorosis; Vector; Excretion of Honeydew
