About this episode

Cindy Kron discusses the monitoring and management of the three-cornered alfalfa hopper, an insect vector of grapevine red blotch virus, and the implications for vineyard pest management.

Three-cornered alfalfa hopper (TCAH) is the only confirmed insect vector of grapevine red blotch virus in Vitis vinifera, yet many growers first realize they have the pest only after spotting petiole girdling in the vineyard. Cindy Kron, North Coast IPM Advisor at UC ANR, shares findings from two years of weekly sweep-net monitoring at Oakville Research Station that revealed TCAH adults are present well before bud break, suggesting grapevines are not their preferred host. She explains the insect's life stages, why legumes serve as key feeding and reproductive hosts, and why detecting early instars remains a major challenge for vineyard IPM. Cindy also discusses how degree-day models may help growers better time tillage to reduce TCAH populations and limit grapevine red blotch risk. Resources: 71: New Techniques to Detect Grapevine Leafroll Disease 131: Virus Detection in Grapevines Can a pesky treehopper be foiled because its growth is regulated by temperature? Cindy Kron How to use a model for reduction of three-cornered alfalfa hopper in vineyards Identification of Nonhost Cover Crops of the Three-Cornered Alfalfa Hopper ( Spissistilus festinus ) Use of Ground Covers to Control…

People in this episode

Host: Vineyard Team

Guest: Cindy Kron

Topics covered

• pest management
• grapevine diseases
• insect vectors
• agricultural monitoring
• vineyard management

Keywords

• three-cornered alfalfa hopper
• grapevine red blotch virus
• pest monitoring
• degree-day models
• vineyard IPM
• legumes
• insect life stages

Mentioned in this episode

Organizations: UC ANR, Vineyard Team

Products: grapevine red blotch virus, three-cornered alfalfa hopper, degree-day models, grapevines, legumes, nonhost cover crops, ground covers

Places: Oakville Research Station, Vitis vinifera

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