Fig. 1

Immunofluorescence of A416 antibody and chrysanthemum yellows phytoplasma (CYP) in vibratome sections of Macrosteles quadripunctulatus midguts. In a and b, labeling of CYP cells after 4 h insect feeding on CYP-infected plants. In c and d, A416 antibody acquired through 24 h artificial feeding was directly labeled with a goat anti rabbit FITC-conjugated antibody. In e-h, direct immunofluorescence labeling of A416 antibody with a goat anti rabbit Alexa 633-conjugated antibody (h) followed by CYP labeling (FITC, g) shows the coincidence of the respective signals (f) in insects pre-fed on A416 antibody (24 h) and then on CYP-infected plant (4 h). i, l and m, n are negative controls in which primary and secondary antibody (respectively) was omitted. a, c, e, i, m show bright-field images; b, d, g, h, l, n show fluorescence images; f is the overlay of light and fluorescence images. Bars represent 20 μm