Sodium sulfite (Na 2 SO 3 ) and ethylenediaminetetraacetic acid (EDTA) are commonly added to infected plant homogenate during virus purification to minimize the effects of polyphenolic compounds and virion aggregation, respectively [23, 24] . When sodium sulfite and EDTA were added to the tissue homogenization buffer, and the subsequent purified CYDV-RPV virions were fed to aphids through ParafilmH membranes, the virus was not transmitted in two independent experiments (Table 1 ). In contrast, CYDV-RPV purified without these additives was highly transmissible by aphids (.95%) in six independent experiments (Table 1) . To determine whether treated virions were unstable and being degraded during membrane feeding by aphids, treated and non-treated virions were collected from the diet following the acquisition access period (AAP) and analyzed by transmission electron microscopy (TEM). Importantly, treated virions remained intact in the diet following the AAP (Fig. 1 ). Treated and untreated virions were morphologically indistinguishable at this point ( Fig. 1) . Broken capsids and capsid swelling were not observed, indicating virions were structurally stable for transmission (Fig. 1) .