1a. Objectives (from AD-416):
Assess feeding deterrence effects of Cyazypyr on potato psylllid to prevent or minimize transmission of zebra chip potato disease.
1b. Approach (from AD-416):
Cyazypyr, a DuPont product has been shown to deter feeding and oviposition in Hemipteran insect vectors (e.g., whiteflies and thrips) and preventing disease transmission to vegetable crops. Potato plants in the greenhouse and small field cages will be treated with Cyazypyr and exposed to liberibacter-infective potato psyllids. After insect exposure, the plants will be monitored for zebra chip symptoms to estimate disease incidence.
3. Progress Report:
The work summarized in this progress report relates to objective number 3 in the Project Plan for 018-00D: 3. Develop economical, sustainable, and ecologically sound methods for control of aphids, wireworms, and secondary pests of potatoes; and objective number 2 in the Project Plan for 020-00D: 2. Develop bio-intensive methods to manage insect vectors of zebra chip and purple top diseases. The bacterium Liberibacter that causes zebra chip is rapidly transmitted to potato by the potato psyllid and pesticides may have limited disease control as they may not kill the insect fast enough to prevent its transmission to potato. Therefore, there is an urgent need to develop management tools that have deterrence and repellency effects to potato psyllid feeding and egg oviposition. Laboratory and field experiments assessed feeding deterrence effects of Cyazypyr insecticide on potato psyllid to prevent or minimize transmission of zebra chip. It was found that foliar applications of Cyazypyr are effective in deterring feeding and killing the potato psyllid within 24 hours, thereby suppressing the psyllid population rapidly. However, the product did not prevent transmission of Liberibacter to potato plants by the potato psyllid as its does not stop feeding during the first six hours, crucial period during which the potato psyllid can effectively transmit Liberibacter to potato plants. Information from this research is very useful and will be incorporated in integrated pest management programs for potato psyllid control to help potato growers rapidly suppress populations of this psyllid and minimize losses due zebra chip.