Effect of Ipomoea host plants on stylet penetration behavior of Myzus persicae (Sulzer)

Sweetpotato, Ipomoea batatas L. production is affected by Sweetpotato feathery mottle virus (SPFMV), a non-persistent stylet-borne virus known to also infect wild morning glory plants. It is vectored by various aphid species, among them the green peach aphid (GPA), Myzus persicae (Sulzer). Differences in stylet penetration behavior of M. persicae on Ipomoea spp. could influence transmission of SPFMV.

Our objective was to determine the effect of host plant; sweetpotato cultivars Beauregard and Evangeline and two morning glory species Ipomoea hederecea Jacq. and I. cordatotriloba Dennst., on stylet penetration behaviors associated with acquisition of non-persistent viruses. Experiments were conducted using a Giga 4 DC EPG amplifier. The following parameters were measured for 20 minutes; duration to first probe, duration to first potential drop (pd), number of probes and potential drops, potential drop duration, duration of sub-phases II-1, II-2, and II-3, and number of archlets/pd.

Among the parameters investigated, pd duration, sub-phase II-3 duration and number of archlets/pd were significantly higher in I. hederecea (P < .0001). Duration to first probe was significantly shorter on I. cordatotriloba compared to I. hederecea (P=0.0307).

These results suggest that green peach aphid is more likely to acquire SPFMV from I. hederecea than the other hosts since longer potential drop and sub-phase II-3 durations, and higher numbers of archlets/potential drop are positively associated with acquisition of non-persistent viruses.

Further work is in progress investigating transmission of SPFMV from Ipomoea spp by M. persicae.