Evaluation of inoculation techniques of ZYMV with a susceptible squash variety

Inoculation techniques were evaluated for the transmission of Zucchini Yellow Mosaic Virus (ZYMV) to susceptible squash (Cucurbita pepo L.) variety, Gentry. Two different types of airbrush sprayers (gravity fed and siphon fed) were evaluated in comparison to the standard method of rub inoculating leaves dusted with carborundum abrasive. In addition, the number of inoculations (1-3) with the airbrush sprayers and whether the carborundum dust was directly applied to leaves or mixed with the inoculum were also evaluated. The standard method consistently had high infection rates of 90% or greater, whereas the airbrush sprayers had inoculation rates of 30%-97%. Whether the carborundum was dusted or applied in the inoculum solution had no impact on infection rate. The greater the number of inoculations the greater the infection rate in two out of three experiments. In conclusion, the airbrush sprayer may be helpful during preliminary screening; however, it should not be relied on as the sole method of inoculation.