Aphid transmissibility and cross-protection effectiveness of an attenuated mutant of zucchini yellow mosaic virus
Journal
Plant Protection Bulletin
Journal Volume
52
Journal Issue
1
Pages
1-16
Date Issued
2010
Author(s)
Abstract
In our previous study, two amino acid substitutions in the HC-Pro gene of a Taiwan severe strain of Zucchini yellow mosaic virus (ZYMV-TN3) generated a mild mutant ZYMV AC (ZAC) that induces attenuated symptoms on squash plants and provides a high degree of cross-protection against the severe virus ZYMV-TN3. In this investigation, aphid transmissibility and cross-protection effectiveness of ZAC were examined. In aphid transmission tests, apterous aphids were collected in glass petri dishes, fasted for 2 hr, and then aphids were allowed a 10 min acquisition access time on plants at 3, 5, 10, and 15 days after inoculation with the infectious virus of severe TN3 or attenuated ZAC. After acquisition, aphids were placed on healthy squash seedlings at one true leaf stage, each with ten insects, and allowed an overnight inoculation access feeding. The results indicated that the mutant virus ZAC loses its aphid transmissibility, even though at the level of virus accumulation as high as that of ZYMV-TN3. In order to facilitate the feasibility for application, cross-protection effectiveness of ZAC was tested in several economic cucurbit crops. When the attenuated virus ZAC was used to protect plants of watermelon, oriental melon and cucumber against the mechanical challenge of a severe recombinant virus ZYMV-Derp V at 5 or 10 days after the protective inoculation, complete cross protection was noticed. Taken together, we conclude that the non-aphid-transmissible ZAC is a valuable mild strain for protecting major cucurbit crops against the severe infection of ZYMV.
Subjects
aphid transmission
mild strain
cross protection
cucurbit
Type
journal article