Cotton – The Call Of The Week Is Aphids (Bollworms Picking Up)

DR. SCOTT STEWART

JACKSON, TENN.
   I’m getting more reports of bollworm moths being observed in fields. Thus far, it appears that our bollworm flight is right on time and pretty typical in size. We will have a better sense of this by next week. Things can change quickly, and the next 14 days is a critical window for scouting and managing bollworm infestations in cotton. Please refer to a previous article about control options for bollworm in cotton … http://news.utcrops.com/2017/07/cotton-insect-update-and-thinking-ahead-about-bollworm/.
   Despite heightened awareness about bollworms in Bt cotton, the most frequent call of the week has concerned aphids. Below are a few reminders about managing aphids and some thoughts about managing a complex of pests that includes aphids.
   Don’t get too excited about aphids. It takes lots of aphids and prolonged infestations to affect yield. However, I have nothing against killing some aphids while managing other pests.
   Belay, Centric and imidacloprid products will NOT adequately control aphids. Resistance to these products is well established. The only products that I am confident will consistently control cotton aphids are Transform, Carbine, and Intruder or Strafer. Bidrin may also provide control, particularly if it has not previously been used in the field.
   Below are the results of a small test we rated in Jackson this week against a moderate infestation of cotton aphids. We’ve only done one rating at 4 days after treatment, but with the exception of Centric, all products provided good suppression of the aphid infestation. Transform provided the best control but Carbine, which is slow acting, should improve by the next rating.
   As you know, we have a Section 18 label for Transform to control plant bugs. It is NOT labeled for aphid control. However, using Transform by itself or as a tank-mix partner is an obvious option for controlling plant bugs when aphids are present.
   Using Bidrin, again by itself or in a tank mix, it worth considering. It may only suppress aphids, but it has the benefit of providing control of plant bugs and stink bugs. ∆
   DR. SCOTT STEWART: IPM Extension Specialist, University of Tennessee