‘Tiny Terrors’… The Soybean Aphid NACAA AM/PIC 2007 Invasive Species: Arrive, Survive, and Thrive ‘Tiny Terrors’… The Soybean Aphid Chris DiFonzo Field Crops Entomology Michigan State University

the Soybean Aphid, Aphis glycines Matsumura Secondary host: Glycine max (soybean) June July August March fundatrix Winter eggs gynoparae males Sept oviparae Primary host: Rhamnus spp. (buckthorn) Fall

General Invasion Process Arrive Thrive Survive

ARRIVE Japan China Siberia U.S. 2000 Australia 1999 Malaysia Philippines Thailand Indonesia Siberia U.S. 2000 Australia 1999

Trade and Tourists direct flights from Asia ARRIE Trade and Tourists direct flights from Asia to Detroit, Chicago, Minneapolis - increase in goods imported from Asia

2000 Discovery ARRIVE Introduction near Chicago? Quebec Ontario Introduction near Chicago? Aphids on plant material? Based on an original map by Rob Venette, U.S. Forest Service

Unexploited resource Lack of Attention ARRIVE SURVIVE Unexploited resource - secondary host (soybean) present - few economic soybean insect pests in the Midwest Lack of Attention ‘No-brainer crop’, ‘GM crop’ Plant - RoundUp - Harvest Didn’t notice initial colonizers

Reproductive biology of aphids SURVIVE Reproductive biology of aphids Partheno- genesis Born ‘pregnant’ Live Birth

key: Presence of the Primary host SURVIVE Rhamnus cathartica also non native & invasive

D. Voegtlin (INHS), Quad Cities, Fall 2006

SURVIVE THRIVE Ontario Quebec 2004 distribution

[Ragsdale lab, Univ. of Minnesota] THRIVE High Reproductive Capacity [Ragsdale lab, Univ. of Minnesota] Total # nymphs 75 73 23 Doubling time (days) 2 1.5 --- Temp 68oF 77oF 86oF 95oF

Tremendous ability to disperse THRIVE Tremendous ability to disperse Saginaw MI, August 1st, 2001 Avg 7,000 SBA per plant X plant population 90% alatoid Potential for 800 million winged SBA generated per acre in early August.

SBA landing on a calm morning. East Lansing, 2005

Jays debug the Orioles. Insects take over SkyDome - Toronto invaded by swarms of aphids. Clouds of bugs descend on downtown streets Aug. 3, 2001. “At least they weren't killer bees.” Jays debug the Orioles. Insects take over SkyDome - Toronto crushes Baltimore By John McCauley bluejays.com 8/3/2001

Inadequate or poorly-timed THRIVE Inadequate or poorly-timed biocontrol native & non-native predators can’t keep up some years entomo- pathogens infect late lack of parasitoids

THRIVE Outbreaks: 2001, 2003, 2005, some in 2007

Feeding from large #s of Aphids sucks plant juices specialized gut removes sugar amino acid limited Other problems: Honey dew Sooty mold

Impact of direct feeding (thousands of SBA per plant) Early (June) infestation Mid/late (July/Aug) infestation 8-29-05 Mervyn Erb

Other impacts of aphid feeding nutrients deficiencies (potassium) may increase loss adequate K K deficient

Local Impact – Yield Loss plant height leaf drop # nodes per plant 10 20 30 40 50 60 UNT D 17 (-70%) Yield, bu/acre Saginaw County, MI 2005 CRU C (-40%) + WAR A B 36 (-30%) Local Impact – Yield Loss plant height leaf drop # nodes per plant # pods per node # beans per pod bean quality

June July August Landscape Impact – Virus transmission Avg # of aphids per trap in squash field (Peaks are made up primarily soybean aphids) 40 80 120 160 June July August 25 9 23 6 22 27 2 16 30 13 Western MI, 2003 # SBA per trap

SBA outbreak years (’01, ’03, ’05) in Michigan Bean common mosaic Cucumber mosaic Watermelon mosaic Zucchini yellows Potato virus Y

---------------------10--------------------- Economic & Social Impact – Increased pesticide use 1999 NASS Survey IL < 1% 1 IN 0% MI 0% MN 0% OH <1% 1 % acreage # of products (permethrin, chlorpyrifos) 2005 NASS Survey IL 9% OH 18% IN MI 42% MN 30% (permethrin, chlorpyrifos, dimethoate, esfenvalerate bifenthrin, cypermethrin, cyhalothrin, cyfluthrin, methyl parathion, thiamethoxam) % acreage # of products ---------------------10---------------------

Post-detection of SBA Concentrated on insecticides scouting techniques thresholds improve application technology Introduction of soybean rust: “the best thing that ever happened to soybean aphid” - increased focus on scouting, spray technology

Aphid Suction Trap Network http://www.ncipmc.org/traps/ Aphid Suction Trap Network - annual prediction

Medium term: Classical biocontrol Foreign collection Climate matching Quarantine, testing Field release

Susceptible accession Long term: Host Plant resistance Pictures courtesy of Dr. Duchen Wang MSU Soybean Breeder Susceptible accession Resistant accession

Annals of the Entomological Society of America A source for more information: Annals of the Entomological Society of America Vol. 97, No. 2, March 2004 SPECIAL FEATURE ON SOYBEAN APHID Soybean Aphid Biology in North America Soybean Aphid in China Assessing the SBA Invasion Aphid identification Suitability of Overwintering Hosts Population Dynamics in China   Soybean Aphid Predators Prospects for Classical Biological Control