The cooler temperatures have slowed population development resutling in lower captures this week but a number of locations are still reporting significant aphid captures. Thankfully, this week we have not yet recovered any green peach aphids or soybean aphids (we still have 4 traps yet to identify from that period). This remains an aphid year and flights are still expecting to continue. If you have not yet vine killed, then...
THE GRAPHS AT THE BOTTOM OF THE PAGE ARE LAST WEEK"S THEY WILL BE UPDATED WHEN ALL TRAPS ARE PROCESSED!
Scouting & treating 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 standard broad-spectrum insecticides are not an effective control for PVY (by the time the aphid has been exposed and dies, it can have moved PVY inoculum into and, more importantly, within the field.
- the use of feeding suppressing insecticides, such as Fulfill (Syngenta Crop Protection) or Beleaf (FMC Corp.) 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.
- in table stock potatoes, a treatment threshold of 30 aphids /100 leaves should deter yield loss due to aphid feeding
*We're a little behind this week, traps are full of other insects (possibly envious of all the attention aphids are getting!) If needed, contact the lab at 218.281.8633 and ask for Ian or Nate...
Weekly Trap Catch (click on the image for larger version)
Cumulative Seasonal Catch (click on the image for larger version)