Trap Catches to July 14-21, 2023.
With 14 traps reporting, we've seen a jump in aphid number this week. A total of 81 PVY vectoring aphids were recovered. Leading the vector species were English grain aphids and soybean aphids. Much of the small grains are starting to mature with an associated decrease in food quality (from the aphids' point of view) and we can expect to see increasing numbers of grain aphids being capture in the traps. Soybean aphids seem to also be on the move.Our populations are similar to last year at this time and very close to the 2013-2020 average. In most years, our aphid populations tend to rapidly increase through August. During the growing season, aphids are all female and give birth to live daughters. Colonies of aphids you find on plants are generally non-winged; they feed, have daughters and grow the colonies. Crowded or a decrease in the food quality of their host plants triggers the development of winged forms that disperse to establish new colonies. As average daily temperatures increase, aphid populations will tend to reproduce more rapidly, leading to increasingly dense aphid populations on host plants. Consequently, the maturing hosts colonies feed upon through July and the associated higher temperatures drive the development of aphid colonies. As the population gets larger, they not only get more crowded but feed more on their host. The result is the creation of winged forms in multiple species during August.
Consequently, we may continue to see increases through the coming weeks.
So, you keep scouting and we'll keep counting.
Scouting for aphids in potatoes: