Eriophyid Mites

1. Eriophyid Mites Robert Hadad Cornell Vegetable Program rgh26@cornell.edu 585-739-4068

2. Tiny Mite, Big Trouble

3. Can You See Me Now? 10x

4. Can You See Me Now? 32x

5. Here I Am 400x

6. Symptoms in Garlic • Shows up in storage

7. Symptoms in Garlic • Shows up in storage • Bulbs don’t hold up

8. Symptoms in Garlic • Shows up in storage • Bulbs don’t hold up • Deteriorates over time

9. Symptoms in Garlic • Shows up in storage • Bulbs don’t hold up • Deteriorates over time • Allows secondary rots to enter

10. Injury • In storage, feeding injury is seen as sunken brown spots on garlic cloves. • Feeding damage on garlic leads to drying of cloves

11. Mites Feed on the Cloves • Mites feed on the cloves by rasping surface • Can see them if you have really good hand lens • Appear to look almost like tiny thrips

12. In The Field • If the infested cloves survive the winter, shoots will begin to grow • This early growth will appear stunted, twisted, and the normally green stems will have streaks. • We have seen these symptoms before • Could be the reason for early fusarium infection • If fusarium doesn’t take down the cloves then plants might outgrow this early damage.

13. Stunted and Streaked

14. Management • E. mites can be found on conifers, shrubs, and landscape bedding plants. • Populations rise and fall • One thought is that hot dry weather may shift their feeding to onions, garlic, and other bulbs.

15. Management • Sample your seed stock at harvest. Pick out 15-20 random bulbs and peel back. Use strong hand lens and look for mites. • Cold storage can help reduce populations from multiplying • Oregon State suggests soaknseed stock for 24 hours just prior to planting in a 2% soap and 2% mineral oil bath. • Question: if mites are detected at harvest, what about soaking treatment at this point then dry?

16. Management • Other option of management is heating garlic • During the drying process, have temps between 113-119F. • How long? • Do Not Go Above 120F due to waxy breakdown. • After brief high temp, reduce temp to between 100F- 110F for remainder of drying. • Populations multiply around 77F with 80-95% RH. So if you had found mites or suspect mites, keep temps lower. • Inspect storage garlic every few weeks.

17. Other Practices • Mites reside in soil as well. Rotations of 4years or longer. • Wet soils can reduce populations. • Avoid curing or storing garlic where bedding plants were grown • No pesticides registered in NY for this pest

18. Might Be Mites • Other mites we deal with include Wheat Curl mite. • Found in wheat and other cereal grain crops • Was found in NY about 8 years ago.

19. Wheat Leaf Curl Mites • Avoid using grain cover crops just prior to garlic. • These two mites might be related • Wheat Curl mite found in southern Midwest where it causes from minor to severe damage on grass covers • Can pass virus to some grains –wheat streak mosaic virus • Wheat Curl mite feeds on damaged garlic tissue • Eriophyid mites feeds on healthy tissue

20. Something New • ????????

21. Twisted

22. Fuzzy Orange

23. Twisted Orange Fuzzy Scape Disease Colletotrichum sp. is a newer disease Showed up a couple of seasons ago Attacks scapes First causes twisting Then water soaked area on scape stem Then gets orange fuzzy sporulation Then scape rots at that point breaking off. Could also call it Self De-Scaping disease Might be similar to celery leaf curl found in Canada