Grape Flea Beetle - Commercial Fruit Production in Minnesota
Grape Flea Beetle - Commercial Fruit Production in Minnesota
Grape Flea Beetle - Commercial Fruit Production in Minnesota
You also want an ePaper? Increase the reach of your titles
YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.
Damage<strong>Grape</strong> flea beetle adult on adamaged bud (T.L. Galvan & E.C.Burkness, U of MN)Damage is caused by adult beetles feed<strong>in</strong>g onprimary buds, which prevents them from develop<strong>in</strong>g<strong>in</strong>to shoots, thus result<strong>in</strong>g <strong>in</strong> a decreased yield. Thegreatest economic loss occurs when beetles feed onbuds from “bud swell” until the “first leaf separatesfrom the shoot tip” stages (see Appendix A). Onceshoot growth reaches 7 cm, damage caused by thegrape flea beetle normally does not affect yield.Location of v<strong>in</strong>es can affect the <strong>in</strong>tensity of an<strong>in</strong>festation, with v<strong>in</strong>es on the borders of the v<strong>in</strong>eyardand next to wooded areas hav<strong>in</strong>g higher <strong>in</strong>festations.In addition, weather can also affect the <strong>in</strong>tensity ofthe damage. Cooler spr<strong>in</strong>gs will extend the period ofdevelopment when buds are more susceptible to thebeetle feed<strong>in</strong>g, thus <strong>in</strong>creas<strong>in</strong>g the chance ofeconomic loss.Although primary damage is caused by adult fleabeetle to the develop<strong>in</strong>g buds, larval damage canalso occur on the foliage and is typically limited toseveral leaves and v<strong>in</strong>es. However, larval damagedoes not usually affect grape quality or yield.<strong>Grape</strong> flea beetle damage togrape bud (E.C. Burkness & T.L.Galvan, U of MN)ManagementMonitor<strong>in</strong>g<strong>Grape</strong>s should be sampled dur<strong>in</strong>g the “bud swell” to the “first-leaf separated from shoottip”stages, which is generally dur<strong>in</strong>g late April – early May. Sampl<strong>in</strong>g should be donetwice per week by check<strong>in</strong>g for damaged buds and flea beetle adults. The currentsuggested threshold is 5% damaged buds.Cultural/Physical ControlRemove debris and leaf litter on the edges of wooded areas located near v<strong>in</strong>eyards toelim<strong>in</strong>ate overw<strong>in</strong>ter<strong>in</strong>g sites. In addition, shallow disk<strong>in</strong>g the area between grape rowscan also help destroy overw<strong>in</strong>ter<strong>in</strong>g pupae.Chemical controlSeveral <strong>in</strong>secticides provide good control of grape flea beetle, and can be found <strong>in</strong> theMidwest Small <strong>Fruit</strong> Pest Management Handbook.