Mississippi State just released some very good preliminary data on the efficacy of Transform and Sivanto for sugarcane aphid control during cool temperatures. Cooler temps (<60F) slow the aphids activity down and they do not feed as much and are not taking the product up as fast. For maximum efficacy, apply these two chemicals during the hottest part of the day especially during cooler days.
http://www.mississippi-crops.com/2015/08/24/sugarcane-aphid-control-with-falling-temperatures/
-Sarah Zukoff