Trap Catches Identified to July 19

Greetings!

Trap catches for the week of July 12-19 have increased but are still relatively low.  We now have 12 traps reporting and several more will com online next week.  No Green Peach Aphid to this point but we recovered 2 Damson-Hop aphids and 1 Cannabis aphid.  These populations are lower than last year but we're still including them in our Risk Index calculations.  Soybean aphids remain low but are starting to show in a couple of traps. Most of the other aphids recovered in traps this week were the usual suspects for this time of year, including Cotton/Melon, Black Bean, and Thistle aphids.  Small grain development is advancing and aphid populations in cereals have been noted in a number of locations.  So we can soon expect to start recovering cereal aphids in the traps (and because the 3 most frequent cereal aphid species in MN & ND are PVY vectors, we'll be watching!) 

While numbers are still low to this point, aphids are flying and, if you haven't started scouting, it's time to start. The absence of aphids on potatoes, however doesn't mean there's no risk of PVY.  Non-colonizing aphid vectors can be as important in sp[reading PVY, if not more so, than many of the colonizing species. Remember, the application of oil is recommended as a mechanism of reducing the spread of PVY. 

Aphid Fact of the Week - Aphid reproduction in the summer is parthenogenetic, unfertilized females giving rise to female offspring.  In fact, in the aphid species we monitor, there are no males during the summer.  Adult females give birth to live daughters, which, sometimes in as short a period as several days, will be giving birth to their own daughters.  This system can result in very rapid development of aphid colonies. 

As always, keep on scouting!

Cumulative PVY Vector Risk Index to July 19, 2019

Cumulative PVY Vector Risk Index for the 2018 Season (for comparison) 

Aphid Species Capture and PVY Vector Risk Index for July 12-19, 2019

Cumulative Aphid Species Capture & PVY Vector Risk - To July 19, 2019.

Trap Catches Identified to July 12

Greetings!

Trap catches for the week of July 05-12 remain low.  However, 1 Damson-Hope aphid was recovered from Gully, MN.  This aphid has been reported as being ~1/2 as efficient as Green Peach Aphid, meaning it could be a major player in spreading PVY if we see numbers this season.

Data from other researchers continues to highlight the value of early application of crop oils (e.g. Aphoil, JMS Stylet oil).  Researchers in New Brunswick have also reported additional value in adding either lambda-cyhalothrin insecticides (e.g. Warrior II, Silencer, Grizzly, etc) or the insecticide, Beleaf to oil applications.  All products should be suitable for tank mixing with fungicides (but remember to always check the label! a jar test may also be useful if you have concerns).  No other insecticides tested were found to provide additional efficacy.

While numbers are low to this point, aphids are flying and, if you haven't started, it's time to start...

As always, keep on scouting!

 Cumulative PVY Vector Risk Index Map to June 30, 2019

For Comparison - Cumulative PVY Risk Index For 2018 Season

Aphid Species Capture & PVY Risk July 05-12

Cumulative Aphid Species Capture + PVY Risk - To Week of July 12, 2018