Results of Monitoring Aphids in Northwest Washington Blueberries. Andy Jensen Adjunct Faculty, WSU Dept. of Entomology

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1 Results of Monitoring Aphids in Northwest Washington Blueberries Andy Jensen Adjunct Faculty, WSU Dept. of Entomology

2 A few aphid facts Modern aphids are all parthenogenetic and viviparous, with telescoping generations and seasonal polymorphsm. Most have a single generation of sexual reproduction and egg production per year (holocyclic). Others anholocyclic. Feed on plant phloem (mostly). Most aphids are host-specific. Some aphids host alternate (are heteroecious ), others do not (are monoecious ). Just over 5,000 species worldwide, probably about 1,000 species in western U.S. and Canada, at least 200 species in western Washington.

3 Spring Summer Fall Fundatrix Aphid life cycle Wingless and winged females Egg-laying females, males

Many plant-pathogenic viruses are transmitted by aphids the aphid

4 Aphids as Pests of Crops Feed on phloem sap and can cause direct damage by weakening plants. Many plant-pathogenic viruses are transmitted by aphids the aphid is the vector of the virus. Aphid honeydew can cause damage to fruits and other harvested plant parts.

5 Aphids on Washington Blueberries Hundreds of aphid samples collected as part of WBBC-funded work on scorch virus. Yellow pan traps aimed to capture flying aphids in and adjacent to blueberry fields. Vacuum samples aimed to capture aphids that actually colonize and reproduce on blueberries.

6 Simple Questions in this Work Blueberry-colonizing aphids: Which species are in your fields? How abundant are they and when? Non-colonizing winged aphids: Which species are flying in your blueberry producing region? What plants and crops might they be coming from?

7 Blueberry-colonizing aphids Species known to feed on blueberry: Aphis fabae (black bean aphid) Aphis gossypii (cotton or melon aphid) Aphis vaccinii Aulacorthum solani (foxglove aphid) Ericaphis scammelli Illinoia azaleae Illinoia borealis Illinoia pepperi Macrosiphum euphorbiae (potato aphid) Myzus persicae (green peach aphid)

8 Let s Subtract the Polyphagous Species

9 Blueberry-colonizing aphids Species known to feed on blueberry: Aphis fabae (black bean aphid) Aphis gossypii (cotton or melon aphid) Aphis vaccinii Aulacorthum solani (foxglove aphid) Ericaphis scammelli Illinoia azaleae Illinoia borealis Illinoia pepperi Macrosiphum euphorbiae (potato aphid) Myzus persicae (green peach aphid)

10 Blueberry-colonizing aphids Species known to feed on blueberry that specialize on Vaccinium and relatives: Aphis vaccinii Ericaphis scammelli Illinoia azaleae Illinoia borealis Illinoia pepperi So, which species were found in western Washington fields in 2016 and 2017?

11 Blueberry-colonizing aphids Species known to feed on blueberry that specialize on Vaccinium and relatives: Aphis vaccinii Ericaphis scammelli (=Ericaphis fimbriata?) Illinoia azaleae Illinoia borealis Illinoia pepperi So, which species were found in western Washington fields in 2016 and 2017?

12 Blueberry-colonizing aphids Species known to feed on blueberry that specialize on Vaccinium and relatives: Aphis vaccinii Ericaphis Illinoia azaleae Illinoia borealis Illinoia pepperi So, which species were found in western Washington fields in 2016 and 2017?

13 Blueberry-colonizing aphids Species known to feed on blueberry that specialize on Vaccinium and relatives: Aphis vaccinii Ericaphis Illinoia azaleae Illinoia borealis Illinoia pepperi So, which species were found in western Washington fields in 2016 and 2017?

14 Blueberry-colonizing aphids Species known to feed on blueberry that specialize on Vaccinium and relatives: Aphis vaccinii Ericaphis Illinoia So, which species were found in western Washington fields in 2016 and 2017?

15 Aphids on the sampled blueberries, 2017, across all 5 fields All aphids counted in all sample types Colonizing aphids total 9125 Ericaphis winged 499 Ericaphis wingless 1633 Illinoia winged 153 Illinoia wingless 996 Nymphs 5844

16 Colonizing aphids by field, 2017 Ericaphis winged Ericaphis wingless Illinoia winged Illinoia wingless SK1 SK3 WH1 WH5 WH

17 Total Colonizing Aphids, Field SK1, 2017 only 700 Total Colonizing Aphids /8 5/15 5/22 5/29 6/5 6/12 6/19 6/26 7/3 7/10 7/17 7/24 7/31 8/7 8/14 8/21 8/28

18 Total Colonizing Aphids, Field WH7, 2017 only 500 Total colonizing /31 6/7 6/14 6/21 6/28 7/5 7/12 7/19 7/26 8/2 8/9 8/16 8/23

19 Non-Colonizing Aphids Across All Sites, 2017, Traps in Weeds Species Common Name Host Plants Total Nasonovia ribis-nigri Currant-lettuce Various plants, mostly aphid Compositae 490 Acyrthosiphon pisum Pea aphid Many legumes 459 Aphis fabae Black bean aphid Polyphagous 381 Myzus persicae Green peach aphid Polyphagous, esp. potato 288 Hyperomyzus lactucae Blackcurrantsowthistle aphid Sowthistles (Sonchus) 218 Brevicoryne brassicae Cabbage aphid Many crucifers 133 Uroleucon sp. Mostly sowthistle aphid Sowthistles (Sonchus) 123 Rhopalosiphum padi Bird cherry-oat aphid Grasses 99 Euceraphis Birch aphid Birches 90 Aphis spiraecola Spirea aphid Polyphagous 81 Lipaphis pseudobrassicae Mustard aphid Crucifers 77 Pemphigus Cottonwoods, roots of many other plants 71

20 Winged Aphids in Field Traps 2017 Species Common name Total across sites Ericaphis Blueberry aphid 102 Myzus persicae Green peach aphid 100 Acyrthosiphon pisum Pea aphid 94 Euceraphis Birch aphid 59 Hyperomyzus lactucae Blackcurrant-sowthistle aphid 56 Aphis fabae Black bean aphid 53 Rhopalosiphum padi Bird cherry-oat aphid 44 Illinoia Blueberry aphid 2 34 Uroleucon sp. Mostly sowthistle aphid 31 Hyadaphis Honeysuckle aphid 25 Pterocallis alni Alder aphid 24 Brevicoryne brassicae Cabbage aphid 22

21 Relevance to Scorch Virus Ericaphis is the most effective vector of scorch among the aphids that have been tested (Illinoia has apparently not been tested). Although non-colonizing aphids can be important in transmission of non-persistent viruses like scorch, the abundance of Ericaphis and Illionoia in blueberry fields suggests that they are likely the most important for virus spread.

22 Other Issues Many common crop pest aphids are flying across the region, probably affecting other crops in various ways. The abundance of colonizing aphids may be related to pesticides used to control SWD. For example, pyethroids often cause aphids to flair. To limit scorch spread in blueberry, it may be necessary to develop integrated pest management strategies that successfully manage SWD and aphids. This would be a non-trivial accomplishment!

23 Acknowledgements Funding: WBBC, WSCPR Sample cleaning: Betsy Schacht Sample gatherers

Integrated Control of Aphids. Michelangelo La Spina, PhD

Integrated Control of Aphids. Michelangelo La Spina, PhD Integrated Control of Aphids Michelangelo La Spina, PhD What is an aphid? Also named: plant lice; green flies Sap-sucking insects Soft bodies Small: 1.0-4 mm Cornicles Feed on many hosts: Monocotyledons