For a host-pathogen incompatible response (i.e., plant exhibits resistance), the plant must recognize the pathogen quickly and then rapidly begin the process of marshalling its defenses. Recent experiments from our laboratories shows that in new Verticillium wilt resistant cottons, mRNA levels for genes involved in lignin and phytoalexin synthesis reach maximal activity 12 hours after inoculation with conidia of Verticillium dahliae (defoliating isolate V-76). Since the new resistant cultivars already exhibit early recognition of the pathogen, it behooves us to focus on improving other defense mechanisms in order to further increase resistance. Numerous studies from our laboratories have demonstrated that the rapid biosynthesis of the phytoalexins play an essential role in cotton's active defense response. Because of the phytoalexin's critical role in resistance, we have focused our research on enhancing the potency of these compounds via two routes: 1) alter the current cotton phytoalexin composition and 2) introduce genes from related genera that will yield different more toxic phytoalexins.