Iris Yellow Spot Virus: Emergency Field Day

EMERGENCY RESPONSE FIELD WORKSHOP
Best Management Practices for Iris Yellow Spot Virus on Onions

Katsu Kobashigawa Farm

85-330 Waianae Valley Road

Waianae, HI 96792-2829

Friday, May 4, 2012

2:00 pm – 4:00 pm

Sponsored by UH CTAHR, LIFE and RMH

For more information, please contact Jari Sugano or Lynn Bessara at 622-4185

In July 2010, Maui Extension agent, Robin Shimabuku detected viral symptoms on bulb onions in Kula, Maui. Samples were submitted to UH CTAHR. Dr. John Hu and Wayne Borth confirmed Iris Yellow Spot virus on Onions. Through field scouting efforts, the IYSV was found on bulb onions in Ewa, Oahu on November 2011 and recently confirmed on green onions in Waianae on April 2012. Iris Yellow Spot Virus is a tospovirus, related to the devastating virus diseases, tomato spotted wilt virus

We will be holding an educational workshop on IYSV on Friday, May 4, 2012 at Katsu Kobashigawa’s farm in Waianae to educate growers about the IYSV symptoms, insect vector, control strategies, insecticidal field evaluations conducted in Maui and the effect of good spray coverage in onion production. CTAHR's Extension agents, virology, entomology, and IR4 (minor crop registration) Extension specialists will provide the training for the day's event.

**For non-onion producers, we will be discussing insecticide resistance management, maximum allowable applications of new crop protection chemicals, chemical rotations with limited approved products, and utilizing Kaolin clay products to demonstrate the effect of spray coverage on a crop such as onion.

• What is Iris Yellow Spot Virus?
• Insect vector: Onion thrips
• IYSV symptoms on bulb and green onions
• Onion thrips biology and control
• Host Plants
• Distribution in Hawaii
• Best management program for IYSV
• Clean start with virus free plants
• Field sanitation to minimize vector and pathogen 
• Crop management practices
• Field scouting for symptoms
• Weed management and ID
• Crop rotation program to minimize thrips population
• Fallow free fallow period to reduce host plant inoculum and insect vectors
• Evaluate cultural management techniques such as varietal selections, overhead irrigation, compost, straw mulch and reflective mulches
• Effectively manage onion thrips populations via implementation of an insecticidal management program
• Obtain good spray coverage
• Apply only approved insecticides for use in Hawaii on onions
• Note maximum application limitations
• Rotate insecticides between classes to minimize resistance
• Use a spreader-sticker to increase spray efficacy
• Read and follow the label directions
• Pay attention to key words such as pre-harvest intervals (PHI), re-entry intervals (REI),personal protective equipment (PPE), spray interval, maximum number of applications, etc.
• Keep good records of spray applications. Important information such as rates, frequency, treatment area, damage, etc. should be documented
  
• Field evaluation of IYSV symptoms on green onions     
• Spray coverage field demonstration using Kaolin clay to show different levels of coverage  
• Overview of LIFE and Risk Management Hawaii

Open to everyone without regard to race, age, sex, color or disability. Educational activities are accessible for individuals with disabilities. Workshop is free.

DIRECTIONS:
Enter Waianae on Farrington Highway. Take a right onto Waianae vValley Road before the police station. Go 1 -1.5 miles on Waianae Valley Road and 85-330 Waianae Valley Road will be on your left hand side. Look for field day signs and / or cones.

HDOA Pesticide License Holders: This workshop has been approved for 2.0 CEUs for categories Private 1, Commercial 1a and 10 by the HDOA.  The assigned class number is 838. Please bring your valid pesticide card to the workshop to receive credits.