Trap Catches Identified to Sept 16

Greetings!

Reporting what will likely be the last report of the season, we received trap contents from two locations this week, neither of which contained any aphids.  Consequently, neither cumulative trap captures nor PVY Vector Risk Index values change this week...


As a seasonal wrap-up, we can say the PVY Vector Risk Index for 2016 was less than it was for almost all locations in 2015.  Significantly fewer green peach aphids were recovered (only 17 as opposed to the 143 GPA captured last year) and soybean aphid populations remained low throughout the season with the August dispersal event never really occurring (only 25 soybean aphids were recovered in 2016 as compared to 2189 soybean aphids in 2015!).  Most of the aphid vectors recovered in traps in 2016 were only moderately efficient vectors compared to green peach aphids as well, keeping the PVY Vector Risk Index numbers low through the summer.

Here's wishing you all good numbers in the winter grow outs!

The PVY Vector Risk Index Not all species of aphid are equally efficient at transmitting PVY, some are better than others (green peach being the most efficient vector of PVY).  So, the total number of aphids in a trap don't necessarily reflect just how much vector pressure there is at that location. The PVY Vector Risk Index compares aphid numbers, incorporating their relative vector efficiency compared to the Queen of PVY vectors (green peach aphid!).  Using averaged reference comparisons from the literature, we multiply the number of each aphid species captured by it's efficiency compared to Green Peach Aphid to more accurately depict risk posed by the species being trapped.  We then sum the totals.  The PVY-VRI values are presented on the tables below but also on maps comparing current cumulative risk to the total risk from the sample sites of last year (to compare with your local winter grow out results).  Click on the map for full sized image.

The First map represents the current cumulative PVY Vector Risk Index values in 2016.  The Second represents the cumulative seasonal PVY Vector Risk Index values from 2015.

 

 

Aphid Alert Trap Catch Identified Sept 12-16

 

Seasonal Aphid Trap Catches for 2016

 

 

Trap Catches Identified to Sept 09.

Greetings!

Only 4 traps reporting again this week, Erskine, Hoople, Lake of the Woods and Tappen.  There were no aphid vectors in any of them.  Consequently, the PVY Vector Risk Index Values have not changed from last week.  The number of mosquitoes in the traps was a bit depressing, even for someone living in northern Minnesota!

Most fields are done, so I suspect there isn't much green left out there.  In case there are a few fields left with live vines....

Scouting for aphids in potatoes:

- Select leaves from the lower to mid canopy.  Lower, older leaves will have more established colonies and aphids prefer the balance of nutrients found here; aphids are rarely found on leaves in the upper canopy.

- Avoid leaves on the ground or in contact with the soil.

- In seed potatoes there is only a threshold for PLRV (10 aphids/100 leaves), reactive application of insecticides an effective control for PVY.

- The use of feeding suppressing insecticides, such as pymetrozine (Fulfill®) or flonicamid (Beleaf®) and refined crop oils, such as Aphoil and JMS Stylet Oil, at or prior to field colonization by aphids may reduce the transmission of PVY within fields. Some other insecticides, such as clothianidin (Belay®), imidacloprid (Admire Pro® or Provado®), and spirotetramat (Movento®), have also been demonstrated to reduce the transmission of PVY.

- In table stock potatoes, a treatment threshold of 30 aphids /100 leaves should deter yield loss due to aphid feeding.

The PVY Vector Risk Index

Not all species of aphid are equally efficient at transmitting PVY, some are better than others (green peach being the most efficient vector of PVY).  So, the total number of aphids in a trap don't necessarily reflect just how much vector pressure there is at that location. The PVY Vector Risk Index compares aphid numbers, incorporating their relative vector efficiency compared to the Queen of PVY vectors (green peach aphid!).  Using averaged reference comparisons from the literature, we multiply the number of each aphid species captured by it's efficiency compared to Green Peach Aphid to more accurately depict risk posed by the species being trapped.  We then sum the totals.  The PVY-VRI values are presented on the tables below but also on maps comparing current cumulative risk to the total risk from the sample sites of last year (to compare with your local winter grow out results).  Click on the map for full sized image.

The First map represents the current cumulative PVY Vector Risk Index values up to Sept 09, 2016.  The Second represents the cumulative seasonal PVY Vector Risk Index values from 2015.

 

 

 Aphid Alert Trap Catch Identified Sept 05-09

 

Seasonal Aphid Trap Catches to Sept 09, 2016

Trap Catches Identified to Sept. 02

Greetings!

Only 4 traps reporting this week and all were very low.  One green peach aphid was recovered in the Sabin trap.  PVY Vector Risk Index numbers remain low.

We do need to report an error in our maps from last year - 2015 maps on the previous reported from this year actually shoeed trap capture and not PVY Risk Index values.  This has been corrected.  It is still interesting to compare the two years; averaged over all sites, the Cumulative PVY Risk Index values in 2016 are approximately only 1/10 what they were in 2015.

For those areas that have not yet vine killed, late season movement of inoculum in fields can still be an important  source of PVY.  So, if there's green material in the field, keep scouting....

Scouting for aphids in potatoes:

- Select leaves from the lower to mid canopy.  Lower, older leaves will have more established colonies and aphids prefer the balance of nutrients found here; aphids are rarely found on leaves in the upper canopy.

 - Avoid leaves on the ground or in contact with the soil.

 - In seed potatoes there is only a threshold for PLRV (10 aphids/100 leaves), reactive application of insecticides an effective control for PVY.

 - The use of feeding suppressing insecticides, such as pymetrozine (Fulfill®) or flonicamid (Beleaf®) and refined crop oils, such as Aphoil and JMS Stylet Oil, at or prior to field colonization by aphids may reduce the transmission of PVY within fields. Some other insecticides, such as clothianidin (Belay®), imidacloprid (Admire Pro® or Provado®), and spirotetramat (Movento®), have also been demonstrated to reduce the transmission of PVY.

- In table stock potatoes, a treatment threshold of 30 aphids /100 leaves should deter yield loss due to aphid feeding.

The PVY Vector Risk Index

Not all species of aphid are equally efficient at transmitting PVY, some are better than others (green peach being the most efficient vector of PVY).  So, the total number of aphids in a trap don't necessarily reflect just how much vector pressure there is at that location. The PVY Vector Risk Index compares aphid numbers, incorporating their relative vector efficiency compared to the Queen of PVY vectors (green peach aphid!).  Using averaged reference comparisons from the literature, we multiply the number of each aphid species captured by it's efficiency camopred to Green Peach Aphid to more accurately depict risk posed by the species being trapped.  We then sum the totals.  The PVY-VRI values are presented on the tables below but also on maps comparing current cumulative risk to the total risk from the sample sites of last year (to compare with your local winter grow out results).  Click on the map for full sized image.

The First map represents the current cumulative PVY Risk Index values up to July 22, 2016.  The Second represents the cumulative seasonal PVY Risk Index values from 2015.

 

 

Aphid Alert Trap Catch Identified the Week of Aug 28 - Sep 02 

 

Seasonal Aphid Alert Trap Catches to Sept 02, 2016

.

Trap Catches Identified to 7-22

Greetings!

Aphid numbers remain relatively low but cereals are starting to dry in all areas and we can expect aphids associated with those crops to start moving into potatoes.  Consequently, we can't relax yet!

So - Keep Scouting!

Scouting for aphids in potatoes:

- Select leaves from the lower to mid canopy.  Lower, older leaves will have more established colonies and aphids prefer the balance of nutrients found here; aphids are rarely found on leaves in the upper canopy.

 - Avoid leaves on the ground or in contact with the soil.

 - In seed potatoes there is only a threshold for PLRV (10 aphids/100 leaves), reactive application of insecticides an effective control for PVY.

 - The use of feeding suppressing insecticides, such as pymetrozine (Fulfill®) or flonicamid (Beleaf®) and refined crop oils, such as Aphoil and JMS Stylet Oil, at or prior to field colonization by aphids may reduce the transmission of PVY within fields. Some other insecticides, such as clothianidin (Belay®), imidacloprid (Admire Pro® or Provado®), and spirotetramat (Movento®), have also been demonstrated to reduce the transmission of PVY.

- In table stock potatoes, a treatment threshold of 30 aphids /100 leaves should deter yield loss due to aphid feeding.

The PVY Vector Risk Index

Not all species of aphid are equally efficient at transmitting PVY, some are better than others (green peach being the most efficient vector of PVY).  So, the total number of aphids in a trap don't necessarily reflect just how much vector pressure there is at that location. The PVY Vector Risk Index compares aphid numbers, incorporating their relative vector efficiency compared to the Queen of PVY vectors (green peach aphid!).  Using averaged reference comparisons from the literature, we multiply the number of each aphid species captured by it's efficiency camopred to Green Peach Aphid to more accurately depict risk posed by the species being trapped.  We then sum the totals.  The PVY-VRI values are presented on the tables below but also on maps comparing current cumulative risk to the total risk from the sample sites of last year (to compare with your local winter grow out results).  Click on the map for full sized image.

The First map represents the current cumulative PVY Risk Index values up to July 22, 2016.  The Second represents the cumulative seasonal PVY Risk Index values from 2015.

 

Trap Catches Identified the Week of Aug 22-26

Greetings

Trap capture numbers remain low as do the PVY Risk Index values.  As the season winds down and night time temperatures decrease, we expect this to trend through.  Several sites did not report this week and if trap contents come in early next week, we will add them to the report.

Soybean aphids have still not shown in high numbers and their movement to overwintering hosts will likely being soon.

Scouting for aphids in potatoes: - Select leaves from the lower to mid canopy.  Lower, older leaves will have more established colonies and aphids prefer the balance of nutrients found here; aphids are rarely found on leaves in the upper canopy.
- Avoid leaves on the ground or in contact with the soil. - In seed potatoes there is only a threshold for PLRV (10 aphids/100 leaves), reactive application of insecticides an effective control for PVY. - The use of feeding suppressing insecticides, such as pymetrozine (Fulfill®) or flonicamid (Beleaf®) and refined crop oils, such as Aphoil and JMS Stylet Oil, at or prior to field colonization by aphids may reduce the transmission of PVY within fields. Some other insecticides, such as clothianidin (Belay®), imidacloprid (Admire Pro® or Provado®), and spirotetramat (Movento®), have also been demonstrated to reduce the transmission of PVY. - In table stock potatoes, a treatment threshold of 30 aphids /100 leaves should deter yield loss due to aphid feeding.
The PVY Risk Index Index Not all species of aphid are equally efficient at transmitting PVY, some are better than others (green peach being the most efficient vector of PVY).  So, the total number of aphids in a trap don't necessarily reflect just how much vector pressure there is at that location. The PVY Vector Risk Index compares aphid numbers, incorporating their relative vector efficiency compared to the Queen of PVY vectors (green peach aphid!).  Using averaged reference comparisons from the literature, we multiply the number of each aphid species captured by it's efficiency camopred to Green Peach Aphid to more accurately depict risk posed by the species being trapped.  We then sum the totals.  The PVY-VRI values are presented on the tables below but also on maps comparing current cumulative risk to the total risk from the sample sites of last year (to compare with your local winter grow out results).  Click on the map for full sized image...

 

Aphid Alert Trap Catch Identified Week of Aug 22-26

Seasonal Aphid Alert Trap Catches to Aug 26, 2016.

 

Trap Catches Identified Week of Aug 15-19

Greetings

Another week of low numbers of aphid vector species in most locations.  The exception was central and West Central Minnesota where traps in Staples and Verndale collected 23 and 52 respectively (mostly Bird Cherry Oat aphids), the Perham trap recovered 6 and the Sabin trap recovered 11 aphid vectors.  Verndale and Sabin each had 1 green peach aphid in their catch this week and Crookston had 2.  Soybean aphids were recovered in Sabin, Staples and Verndale as well, but not in excessive numbers.  We have not yet seen a large flight of soybean aphids from the south and as the temperatures get lower and soybeans continue to mature, we may well soon be seeing decreased soybean aphid numbers.

But the catches in Central and West Central MN do indicate there's still aphids out there and much of our PVY is vectored later in the season.  As always, keep scouting....

Scouting for aphids in potatoes: - Select leaves from the lower to mid canopy.  Lower, older leaves will have more established colonies and aphids prefer the balance of nutrients found here; aphids are rarely found on leaves in the upper canopy.
- Avoid leaves on the ground or in contact with the soil. - In seed potatoes there is only a threshold for PLRV (10 aphids/100 leaves), reactive application of insecticides an effective control for PVY. - The use of feeding suppressing insecticides, such as pymetrozine (Fulfill®) or flonicamid (Beleaf®) and refined crop oils, such as Aphoil and JMS Stylet Oil, at or prior to field colonization by aphids may reduce the transmission of PVY within fields. Some other insecticides, such as clothianidin (Belay®), imidacloprid (Admire Pro® or Provado®), and spirotetramat (Movento®), have also been demonstrated to reduce the transmission of PVY. - In table stock potatoes, a treatment threshold of 30 aphids /100 leaves should deter yield loss due to aphid feeding.
The PVY Risk Index Index Not all species of aphid are equally efficient at transmitting PVY, some are better than others (green peach being the most efficient vector of PVY).  So, the total number of aphids in a trap don't necessarily reflect just how much vector pressure there is at that location. The PVY Vector Risk Index compares aphid numbers, incorporating their relative vector efficiency compared to the Queen of PVY vectors (green peach aphid!).  Using averaged reference comparisons from the literature, we multiply the number of each aphid species captured by it's efficiency camopred to Green Peach Aphid to more accurately depict risk posed by the species being trapped.  We then sum the totals.  The PVY-VRI values are presented on the tables below but also on maps comparing current cumulative risk to the total risk from the sample sites of last year (to compare with your local winter grow out results).  Click on the map for full sized image...

 

Aphid Alert Trap Catch Identified Week of Aug13-19 

 

The Seasonal Aphid Alert Trap Catches to Aug 19, 2016

 

Trap Catches Identified Week of Aug 08-12

Greetings!

Aphid vector numbers remain very low compared to last year, and the associated PVY Risk Index values are also not accumulating as they did last year.  But we have reports from SW Minnesota that the numbers of soybean aphids in fields there are increasing rapidly and many winged forms are being found.  Check out Bruce Potter's SW MN IPM Stuff newsletter at:

http://swroc.cfans.umn.edu/ipm-stuff-2016-15
 
If you've got soybeans in, you really need to read Bruce's page!  He presents a lot of information about why you should still be scouting soybeans for aphids - time of year is a lot less important than plant stage for determining if soybeans are still susceptible to yield loss from aphids.

If we get some strong southerly winds, we could be looking at some major immigration events into the upper Red River Valley.  

Meanwhile, with the potential for immigrating soybean aphids, we're still not out of the woods.  Keep Scouting...

Scouting for aphids in potatoes: - Select leaves from the lower to mid canopy.  Lower, older leaves will have more established colonies and aphids prefer the balance of nutrients found here; aphids are rarely found on leaves in the upper canopy.

- Avoid leaves on the ground or in contact with the soil.
- In seed potatoes there is only a threshold for PLRV (10 aphids/100 leaves), reactive application of insecticides an effective control for PVY.
- The use of feeding suppressing insecticides, such as pymetrozine (Fulfill®) or flonicamid (Beleaf®) and refined crop oils, such as Aphoil and JMS Stylet Oil, at or prior to field colonization by aphids may reduce the transmission of PVY within fields. Some other insecticides, such as clothianidin (Belay®), imidacloprid (Admire Pro® or Provado®), and spirotetramat (Movento®), have also been demonstrated to reduce the transmission of PVY. - In table stock potatoes, a treatment threshold of 30 aphids /100 leaves should deter yield loss due to aphid feeding.

The PVY Risk Index
Index Not all species of aphid are equally efficient at transmitting PVY, some are better than others (green peach being the most efficient vector of PVY).  So, the total number of aphids in a trap don't necessarily reflect just how much vector pressure there is at that location. The PVY Vector Risk Index compares aphid numbers, incorporating their relative vector efficiency compared to the Queen of PVY vectors (green peach aphid!).  Using averaged reference comparisons from the literature, we multiply the number of each aphid species captured by it's efficiency camopred to Green Peach Aphid to more accurately depict risk posed by the species being trapped.  We then sum the totals.  The PVY-VRI values are presented on the tables below but also on maps comparing current cumulative risk to the total risk from the sample sites of last year (to compare with your local winter grow out results).  Click on the map for full sized image...

 

Aphid Alert Trap Catch Identified Week of Aug08-12

 

The Seasonal Aphid Alert Trap Catches for 2016

Trap Catches Identified Week of Aug01-05

Greetings!

Aphid vector numbers still remain low in most areas as does the associated PVY Vector Risk Index values.  The annual Soybean aphid summer dispersal flight hasn't yet started, although numbers of soybean aphid are variable throughout MN and ND, most soybean fields are in reproductive stages, meaning we'll see more winged aphids developing from those fields.

While aphid numbers remain low, there have been reports of potato psyllids in western and south central ND.  These insects are the vectors of the Liberibacter bacterium that causes Zebra Chip.  We don't yet know if the psyllids recovered this year are infectious with ZC  but tests are underway.  Even psyllids not carrying the Liberibacter bacterium can injure potatoes via toxins in their saliva injected into the plant when they feed.  This can cause "Psyllid Yellows", characterized by yellow or purple leaves, reduced tuber number and size, malformed tubers, and chaining of tubers.  Scouting and management options are outlined in a Psyllid Management publication which will be posted on the NDSU Potato Extension Webpage (https://www.ag.ndsu.edu/potatoextension), 

Meanwhile. we're still not out of the woods for aphids...

Scouting for aphids in potatoes: - Select leaves from the lower to mid canopy.  Lower, older leaves will have more established colonies and aphids prefer the balance of nutrients found here; aphids are rarely found on leaves in the upper canopy.
 - Avoid leaves on the ground or in contact with the soil.
 - In seed potatoes there is only a threshold for PLRV (10 aphids/100 leaves), reactive application of insecticides an effective control for PVY.
 - The use of feeding suppressing insecticides, such as pymetrozine (Fulfill®) or flonicamid (Beleaf®) and refined crop oils, such as Aphoil and JMS Stylet Oil, at or prior to field colonization by aphids may reduce the transmission of PVY within fields. Some other insecticides, such as clothianidin (Belay®), imidacloprid (Admire Pro® or Provado®), and spirotetramat (Movento®), have also been demonstrated to reduce the transmission of PVY. - In table stock potatoes, a treatment threshold of 30 aphids /100 leaves should deter yield loss due to aphid feeding.
The PVY Vector Risk Index Not all species of aphid are equally efficient at transmitting PVY, some are better than others (green peach being the most efficient vector of PVY).  So, the total number of aphids in a trap don't necessarily reflect just how much vector pressure there is at that location. The PVY Vector Risk Index compares aphid numbers, incorporating their relative vector efficiency compared to the Queen of PVY vectors (green peach aphid!).  Using averaged reference comparisons from the literature, we multiply the number of each aphid species captured by it's efficiency camopred to Green Peach Aphid to more accurately depict risk posed by the species being trapped.  We then sum the totals.  The PVY-VRI values are presented on the tables below but also on maps comparing current cumulative risk to the total risk from the sample sites of last year (to compare with your local winter grow out results).  Click on the map for full sized image...

 

Table of Trap Catches Identified Aug 01-05

 

Graph of Seasonal Trap Catches to Aug 01

Trap Catches Week of July 25-29

 Greetings!

Aphid vector numbers remain low in most areas.  Central MN had higher populations than others but even those were not as high as last year.  

There were no Green Peach and only a few Soybean aphids recovered from traps this week.   However, as Bruce Potter, IPM Specialist in SW MN, always reminds us, once you hear the Harleys making their way to Sturgis, you know the flight of the soybean aphid can't be far away...  He refers to that aphids summer flight as the Sturgis Dispersal Event, and according to Bruce's blog (IPMStuff), the SDE may be starting soon.  That means we may well see increasing numbers of soybean aphids coming our way.



For those of you suffering Colorado Potato Beetles, I sent out a short note on beetles and potential management options.  Dr. Andy Robinson was kind enough to put it on the NDSU Potato Extension website at:  
:  

https://www.ag.ndsu.edu/potatoextension/documents/CPBMNND2016.pdf1

Scouting for aphids in potatoes:
- Select leaves from the lower to mid canopy.  Lower, older leaves will have more established colonies and aphids prefer the balance of nutrients found here; aphids are rarely found on leaves in the upper canopy.
 - Avoid leaves on the ground or in contact with the soil.
 - In seed potatoes there is only a threshold for PLRV (10 aphids/100 leaves), reactive application of insecticides an effective control for PVY.
 - The use of feeding suppressing insecticides, such as pymetrozine (Fulfill®) or flonicamid (Beleaf®) and refined crop oils, such as Aphoil and JMS Stylet Oil, at or prior to field colonization by aphids may reduce the transmission of PVY within fields. Some other insecticides, such as clothianidin (Belay®), imidacloprid (Admire Pro® or Provado®), and spirotetramat (Movento®), have also been demonstrated to reduce the transmission of PVY.
- In table stock potatoes, a treatment threshold of 30 aphids /100 leaves should deter yield loss due to aphid feeding.

The PVY Vector Risk Index
Not all species of aphid are equally efficient at transmitting PVY, some are better than others (green peach being the most efficient vector of PVY).  So, the total number of aphids in a trap don't necessarily reflect just how much vector pressure there is at that location. The PVY Vector Risk Index compares aphid numbers, incorporating their relative vector efficiency compared to the Queen of PVY vectors (green peach aphid!).  Using averaged reference comparisons from the literature, we multiply the number of each aphid species captured by it's efficiency camopred to Green Peach Aphid to more accurately depict risk posed by the species being trapped.  We then sum the totals.  The PVY-VRI values are presented on the tables below but also on maps comparing current cumulative risk to the total risk from the sample sites of last year (to compare with your local winter grow out results).  Click on the map for full sized image...

Here are the week's trap capture by table and the season's cumulative PVY Risk Index graph