WINETECH Technical Yearbook 2020

Aster yellows

A short summary of control measures. In the article, “Indigenous leafhopper transmits aster yellows” in the August 2020 edition of Winetech Technical , light is shed on the leafhopper species Mgenia fuscovaria , which acts as vector to spread aster yellows between plants. Other crops and weed species serve as alternative host plants for the leafhopper, maintaining it during the winter months when the grapevines are dormant. For the successful management of aster yellows, producers must follow a multidisciplinary approach

NOVEMBER 2020

GERT ENGELBRECHT: Vinpro, Olifants River KEYWORDS: Aster yellows, multidisciplinary disease management.

PHOTO 2. A leafhopper caught in an insect trap.

PHOTO 3. Wild radish.

PHOTO 4. Common iceplant.

PHOTO 5. White goosefoot.

PHOTO 6. Blackjack.

PHOTO 7. Sowthistle.

PHOTO 1. A grapevine with typical aster yellows symptoms – note the total absence of grapes.

WINETECH TECHNICAL YEARBOOK 2020 145