text: Some of these substances such as EPTC prevent kaurene formation by inhibiting GGPP cyclization.
full_question: Some of these substances such as EPTC prevent kaurene formation by inhibiting GGPP cyclization. They're not diabetes drugs, but acetolactate synthase is inhibited by a substituted urea group of these substances called sulfonylureas. Variant EPSPS genes provide resistance to a type of these compounds derived from a strain of Agrobacterium tumefaciens. The phenoxy class of these substances act as analogs of IAA and include 2,4- D and 2,4,5-T, which can be contaminated with dioxins. Those postemergence examples of these substances overstimulate ethylene production and cause unsustainable growth by mimicking auxins in dicots. For 10 points, name these commercial chemicals such as Agent Orange and Roundup that are used to kill weeds.
first_sentence: Some of these substances such as EPTC prevent kaurene formation by inhibiting GGPP cyclization.
raw_answer: herbicides [or defoliants; or weedkillers until "kill weeds" is read] 