It has come to my attention that whiteflies are not listed in the Pest Control Handbook under sweet potatoes. This was not an oversight. Having grown sweet potatoes in Tifton the last two years and not having a whitefly problem, I assumed they would not become a problem in sweet potatoes (despite the common name of sweetpotato whitefly). I was wrong. We do have significant populations in sweet potato this year and have recently treated tests for this pest. While populations are not as severe or uniform as they are in more favorable crops, we do have reproduction with some leaves heavily infested (while most look pretty clean).
Upon checking the labels of products we normally use for whitefly in other crops, many are labeled for use in sweet potato, but most do not list whitefly on the label. This does not affect legal use (you are allowed to use a product on any crop where it is labeled for pests not on the label), but probably does alleviate the manufacturer from liability if it does not work as expected. I would expect all of these products to work as well in sweet potato as they do in other crops, but whitefly simply is not on the label (most sweet potato growing areas do not have whiteflies, so why put it on the label?).
The table below lists the products we normally use against whiteflies, whether or not whiteflies appear on the label under sweet potato, the labeled rates, and pre-harvest intervals for sweet potato. As always, check the labels for additional use restrictions and requirements.
Products potentially used in sweet potato with activity against silverleaf whitefly
|Trade name||Whitefly on the label?||Use rate per acre||Pre-harvest interval|
|Platinum 75SG||no||1.66-2.67 oz||At planting, etc.|
|Admire Pro||Yes||4.4-10.5 fl oz||125 days|
|Venom||no||6.5-7.5 oz||At planting, etc.|
|Verimark||no||6.75-13.5 fl oz||At planting, etc.|
|Actara||no||3 oz||14 days|
|Assail||no||2.5-4 oz||7 days|
|Coragen||no||3.5-7.5 fl oz||1 day|
|Fulfill||no||5.5 oz||14 days|
|Movento||Yes||4-5 fl oz||7 days|
|Oberon 2SC||Yes||8-16 fl oz||7 days|
|Sivanto Prime||Yes||10.5-14 fl oz||7 days|
|Venom||no||1-1.5 oz||7 days|
|Knack||Yes||8 fl oz||3 days|