In-Furrow Insecticide Discussion Peanut Notes No. 43 2019

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A couple of weeks ago Rick and I shared e-mails discussing thrips control with in-furrow insecticides. Here is the e-mail string if you are interested. The conversation started when I looked at an article we recently published in the journal Peanut Science comparing thrips control with in-furrow and foliar sprays.

Utilization of Imidacloprid to Control Thrips in Peanut in North Carolina


I think at the very end of the paper we state that imidacloprid and phorate give the same level of protection from thrips. We have really driven home the value of inoculant for BNF in old and new ground (our data support about 200 pounds even in short peanut rotations, a 4x gain in income from the investment over the non-treated) and liquid has been the best delivery method. Adding a liquid insecticide made this easier to do and that reflects a high percentage of growers using AP or generic imidacloprid compared with phorate. And for a period of time after new regs were put in place for metam sodium, farmers used Proline, another liquid in furrow, to suppress CBR. And as we moved production to better land for peanuts that resulted in more sand and less organic matter – and more symptoms of phyto from phorate. In that paper there was value to acephate no matter what in-furrow we used. That does not seem to be holding up as well in some of our Velum Total work (similar trial structure but in more recent years.) Environmentally, which of these, phorate or AP is better? The lock and load system for phorate may be better than a mixing pad for liquid, so phorate might be safer for the handler. What is the difference in generic price of both products?


Phorate is an old organophosphate product that has a much higher toxicity to about everything than the imidacloprid. There is concern over imidacloprid and bee kills, but not in an in furrow context. There is also concern with resistance with the imidacloprid, but ours is not a seed treatment and the higher rate is VERY effective. In my mind, even if the acephate only paid dividends every other year, I think regardless of the in furrow treatment it is still a very cost effective insurance policy for our growers. They have done well in the VC area because we have focused so much attention on getting a good start during that first month and I think that one year with stunting of poor uptake of an in furrow product significantly offsets many years of acephate 3 week post treatments. From a different environmental perspective you could say that phorate offers a benefit of NOT being a neonic and not enhancing the resistance problems that seed treatments are causing. With slight up ticks in TSWV, the phorate obviously offers an advantage there. As we all know, however, NC growers HATE phorate.