Friday, July 11, 2014

Trap Catches Identified to July 11.

Here are the trap catches from the sites we received up to July 11.  Note that sites are on different schedules to send in trap catches (spreading out our identification workload).  As more sites come in, we'll identify their trap catch and update the site on the fly.

We're getting vectors at a few more locations but still seeing low numbers.  Nine of the sites from which we received trap catches had at least one aphid vector.  High counts were at our Linton sites with three and four vectors.  Ada, Erskine, Forest River, Hallock, Hoople, Langdon, and Staples collected no vectors.

Species captured include buckthorn, bird-cherry oat, green bug, english grain, sunflower, cowpea, and pea aphids.  These are all medium efficiency vectors.

Until next week…

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.