Spotted Wing Drosophila – Page 46 – Latest information from the NYS IPM Program

Onondaga County – first find

jec3@cornell.eduJuly 11, 2014July 21, 2015Leave a comment

A single male SWD was caught in one of four yeast-baited apple cider vinegar traps checked on July 8, 2014 and set in a summer raspberry planting, variety Prelude, in Onondaga County by Juliet Carroll, NYS IPM Program. Fruit is ripe and being harvested. At this time the SWD population is very low and although cultural practices such as harvesting fruits frequently and removing rotten fruits from the field will help keep the SWD population down, if susceptible fruit is nearby and ripening, it may prove judicious to consider planning for and beginning an insecticide management program. SWD populations and damage can increase dramatically with favorable weather and susceptible ripe fruits. The weather in central NY has been cool at night with daytime temperatures in the upper 70's and low 80's. Insecticide applications are necessary when SWD populations are high. Insecticides labeled for use in commercial berry production are tabulated on the Cornell Fruit Resources' SWD website. (Accumulated GDD 1169; day length 15:09)

The single male SWD caught in traps checked on July 8, 2014. Note the two black combs on each front leg and the distinctive single spot on each wing.

First find in NY – Suffolk Co.

jec3@cornell.eduJuly 10, 2014July 21, 2015Leave a comment

The first two female SWD of the 2014 growing season were captured over the week of July 3 to 9 in traps monitored by Faruque Zaman, Long Island Horticultural Research and Extension Center, Suffolk County Cornell Cooperative Extension in a yeast-baited trap at a ripening raspberry location in eastern Long Island.

On July 9, examination of 40 fruits found 2 SWD-infested raspberries with egg-laying sites at that location. The raspberry field is surrounded by grapes on one side and blackberries on the other side; no adjacent forest boundaries. No SWD have been captured in traps placed in other locations in Suffolk County, including blueberry, blackberry, grape, forest and a second raspberry site and no fruit infestation was found in raspberries collected from the second site.

At this time the SWD population appears to be very low. Therefore, cultural practices such as harvesting fruits frequently and removing rotten fruits from the field will help keep the SWD population down. Also, remove alternate weed hosts, pokeweed and bittersweet nightshade, from the area before these weeds develop fruit. SWD populations and damage can increase dramatically with favorable weather and susceptible ripe fruits. Insecticide applications are necessary when SWD populations are high. Insecticide control requires frequent applications (5-7 day interval), so delay onset of spraying until sustained captures occur in your area to maximize the utility of the applied materials.

Two female spotted wing Drosophila captured in traps on Long Island on July 9, 2014.

Tiny threads of the SWD egg breathing tubes indicate where an egg was laid in a raspberry. Two eggs were found in 40 fruits examined. — Tiny threads of the SWD egg breathing tubes indicate where an egg was laid in a raspberry. Two eggs were found in 40 fruits examined on July 9, 2014.

First finds outside NY 2

jec3@cornell.eduJuly 3, 2014July 21, 20152 Comments

Reports have come in from Southwest Michigan by Rufus Isaacs, Michigan State University, and Middlesex County in Connecticut by Rich Cowles, CT Agricultural Experiment Station of first catch of SWD. As of today, no one in the NY monitoring network has reported trap catch of SWD. Although the catch in Michigan was of several adults, the report from CT was of a single male.

Because this finding in central CT is of a single adult, don't interpret this as meaning that ripe fruit is immediately at risk. What we have observed in the past is that we can capture a lone adult here or there, but it isn't until we get sustained captures in traps set in susceptible fruit plantings that growers are at risk of infestation.

On Long Island, fruit samples contained no evidence of infestation this week nor were any SWD caught in traps set there in Suffolk County. No other reports of SWD caught in traps have come in from NY. But do stay tuned. The number of other fruit flies being caught in my traps in Wayne County, Sodus Bay area, jumped significantly this week from around 150 per trap last week to almost 1000 other fruit flies per trap.

Although the heat has been unbearable in places...let's cheer, because SWD adults are intolerant of temperatures much above 90F.

Female imposters

jec3@cornell.eduJune 23, 2014Leave a comment

Distinguishing female SWD from other fruit flies caught in traps can prove challenging. Look alike reports to help with identification have come in from Faruque Zaman, Long Island Horticultural Research & Extension Center, Riverhead, NY and Anna Wallingford, NY State Agricultural Experiment Station, Geneva, NY. Faruque's pictures are below. Anna's videos are at Finger Lakes SWD Monitoring, where she posts on Monday afternoons.

SWD look-alikes being caught in the past couple of weeks on Long Island. Note the small, fleshy, and lightly serrated ovipositor.

In this photo, the same fly is on it's belly to show the dorsal view. Note that the black bands are broken in the middle. In SWD the bands are unbroken. — In this photo, the same fly is on it's belly to show the dorsal view. Note that the black bands are broken in the middle. In SWD the bands are continuous.

No finds in NY 2

jec3@cornell.eduJune 20, 20142 Comments

A quick note to let everyone know that no SWD has been caught this week (June 14-20) in traps reporting to the SWD monitoring network in NY.

There is still time to prepare and plan for the actions that will be needed to protect your crops; use this time wisely. Review management tactics, calibrate sprayers, get a cooler for marketing harvested berries, install an accurate thermometer to track daily max/min temperatures, review your insecticide inventory, develop an insecticide rotation program, keep row middles mowed, control weeds, prune to open the plant canopy and reduce shady areas in the planting. Hummingbird feeders anyone?

Monitoring in NY

jec3@cornell.eduJune 20, 2014July 21, 2015Leave a comment

SWD traps are being set out across NY in berry plantings by Cornell Cooperative Extension (CCE) personnel for the 2014 monitoring season. Trap catch results from the following counties will be reporting to the NY distribution map: Albany, Cayuga, Chautauqua, Chemung, Clinton, Columbia, Dutchess, Erie, Herkimer, Livingston, Monroe, Niagara, Onondaga, Ontario, Orange, Orleans, Rensselaer, Saratoga, Schuyler, Seneca, St. Lawrence, Steuben, Suffolk, Tompkins, Ulster, Washington, Wayne, Wyoming, and Yates.

Statewide monitoring wouldn't be possible without the cooperation of all involved: Ginny Carlberg and Betsy Burgeson, Chautauqua County CCE; Jabe Warren, Chemung County CCE; Amy Ivy and Lindsey Pashow, Clinton County CCE; Sharon Bachman, Erie County CCE; Bernie Armata, Herkimer County CCE; Dave Thorp, Livingston County CCE; Paul Hetzler, St. Lawrence County CCE; Stephanie Mehlenbacher, Steuben County CCE; Faruque Zaman, Suffolk County CCE; Emily Cook, Ulster County CCE; Don Gasiewicz, Wyoming County CCE; Laura McDermott, Cara Fraver, Jim O'Connell, and Dan Donohue, Eastern NY Horticulture Program; Deborah Breth and Liz Tee, Lake Ontario Fruit Program; Peter Jentsch and Tim Lampasona, Entomology, Hudson Valley Lab; Greg Loeb and his lab group, Entomology, NYS Ag Experiment Station; and Juliet Carroll, NYS IPM Program, CCE.

Many of us participated in a SWD Workshop, held in May 2014, to hone our skills at identifying these tiny, destructive fruit flies. On hand to teach us the finer points of identifying female and male SWD and many other fruit fly look-alikes were Greg Loeb, Professor of Entomology, and members of his lab, Steve Hesler, Anna Wallingford, and Johanna Elsensohn, and John Jaenike, Professor of Biology and Drosophila expert, University of Rochester.

John Jaenike, Univ. of Rochester, discusses Drosophila biology with Paul Hetzler, St. Lawrence CCE, during the SWD Workshop.

Videos to Monitor By 1

jec3@cornell.eduJune 12, 2014June 19, 20141 Comment

Videos of 2014 SWD trap contents! This year’s monitoring has begun and Anna Wallingford, Postdoctoral Associate in Greg Loeb’s lab at the Experiment Station in Geneva, created a youtube channel, Finger Lakes SWD monitoring, for weekly video updates (every Monday) on what the Loeb lab is finding in traps in and around Geneva. The videos will aim to inform the novice, pointing out various insects that can be found in the traps but also concentrating on those SWD look-a-like drosophilid species that pose challenges when trying to ID the rare, first SWD female(s).

Please post a comment on the Finger Lakes SWD monitoring youtube site or send Anna an email if you have any suggestions on how to make the videos more useful. Also include any ideas for “how to” videos/content that we might produce as Extension materials.

Screen shot of the first SWD youtube video showing trap catch samples.

Alerts & Protecting Fruit

jec3@cornell.eduJune 11, 2014Leave a comment

No SWD has been reported, as of June 11, 2014, from any of the monitoring locations in New York. Any confirmed first trap catch SWD findings will once again be posted on the blog.

Current guidelines for managing SWD are to begin insecticide applications on vulnerable crops when fruit are ripening. Late-season blueberries, blackberries and fall raspberries are especially vulnerable to attack. Less vulnerable, but also at risk, are late season plums, peaches, cherries and grapes, and late harvest summer raspberries, early to mid-season blueberries, and early harvest day-neutral strawberries.

Insecticide table quick guides are linked below and available on the Spotted Wing Drosophila website on Cornell Fruit Resources, www.fruit.cornell.edu. If you are reading this from outside of New York, keep in mind that NY State may be more restrictive on labeling insecticides and there may be additional insecticide options available in your state; contact your local Extension Service for more information.

2014 Labeled insecticides for berry crops

2014 Labeled insecticides for stone fruit & grapes

Where is SWD found?

jec3@cornell.eduMay 21, 2014June 20, 2014Leave a comment

As we gear up for our 2014 monitoring efforts in New York, reports are circulating of new places this invasive and destructive fruit fly is being found. From February through May, 2013, Drosophila suzukii was found for the first time in southern Brazil. Closer to home, spotted wing Drosophila is found in the Canadian provinces to our north and east. To get a baseline for SWD occurrence in the USA, as of the end of 2013, look at the map compiled by Hannah Burrack, entomologist at NC State University.

In New York, entomologist Faruque Zaman, Suffolk County Cornell Cooperative Extension, Long Island, has traps out, but has not caught SWD yet. Peter Jentsch, entomologist at the Hudson Valley Laboratory, has traps out, as does Greg Loeb, entomologist at the NY State Ag Experiment Station in Geneva. So far no SWD detected.

The NY statewide monitoring traps will be set in early June in the following counties - Albany, Cayuga, Chautauqua, Chemung, Clinton, Columbia, Dutchess, Erie, Herkimer, Livingston, Monroe, Niagara, Onondaga, Ontario, Orange, Orleans, Rensselaer, St. Lawrence, Saratoga, Schuyler, Seneca, Steuben, Suffolk, Tioga, Ulster, Washington, Wayne, and Yates. Reports of SWD trap catch will be posted as they come in.

Map of SWD detections in the US, as of 2013. Source: Hannah Burrack, NC State Univ. — **Map of SWD detections in the US, as of 2013.** Source: Hannah Burrack, NC State Univ.

Frozen or baked SWD?

jec3@cornell.eduApril 8, 2014Leave a comment

As we emerge from the clutches of a long and very cold winter, we’re pondering if SWD was killed off…as were many fruit buds in New York. A study in Japan (Kimura 2004) investigating cold and heat tolerance of fruit flies included SWD. Interestingly, SWD is distributed in all three of the climatic regions in Japan from which drosophilid flies were collected for the research, the cool-temperate region (January mean temperature 23 F, August mean temperature 71 F), the warm-temperate region (January mean temperature 39 F, August mean temperature 80 F), and the subtropical region (January mean temperature 64 F, August mean temperature 82 F). Progeny from SWD females collected from each of these regions showed little variation in the range of heat and cold tolerance; the conclusion being that populations don’t gain much improved heat tolerance in the subtropical region or much improved cold tolerance in the cold-temperate region.

To test SWD’s temperature tolerance, flies were held at constant temperature in dark for a 24-hr period to determine the lethal temperature (LT) at which 25%, 50%, and 75% of the flies died. 75% of females die at 28.7 F and 75% of males die at 30.7 F.

Can we start celebrating? With low temperatures dipping into the negative teens this winter, was LT 100% reached? -17 F is certainly well below the LT 75% of 28.7 F. I would argue that a distinct possibility exists that a majority of SWD attempting to overwinter in the New York died this winter. However, remember how small SWD is and that microclimates do exist near buildings, compost piles, etc. where temperature may not drop as low as the recorded air temperature. Also, research has yet to determine if SWD overwinters in New York, so maybe the argument is irrelevant?

Another take home message from the lethal temperature table for SWD is that they die at and above 90 F. Last summer was hot and SWD damage seemed not as severe to many of us as in 2012. Perhaps adult flies died off during periods of 90 F and above this summer. As June nears its end this year, invest in an accurate thermometer and keep track of how hot it gets.

Masahito T. Kimura. 2004. Cold and Heat Tolerance of Drosophilid Flies with Reference to Their Latitudinal Distributions. Oecologia, Vol. 140, No. 3 pp. 442-449.