Insect growth regulators with hydrazide moiety inhibit strigolactone biosynthesis in rice

Abstract

S Supplementary materialStrigolactones (SLs) are carotenoid-derived plant hormones involved in several growth and developmental processes. Also, SLs are allelochemicals that induce the seed germination of root parasitic plants and the hyphal branching of arbuscular mycorrhizal fungi. In this study, to identify novel lead chemicals that inhibit SL biosynthesis, we evaluated the effect of agrochemicals on SL biosynthesis. We found that the diacylhydrazine insect growth regulator, chromafenozide, reduced the endogenous level of 4-deoxyorobanchol (4DO), a major SL in rice. Furthermore, treatment with the same class of insect growth regulator, methoxyfenozide, also resulted in the reduction of 4DO levels in rice root exudates. These results suggest that chromafenozide and methoxyfenozide are novel lead inhibitors of SL biosynthesis.

Fenoxycarb, a carbamate insect growth regulator, inhibits brassinosteroid action

“…[8][9][10] Recently, our group reported that insect growth regulators, chromafenozide and methoxyfenozide, were SL biosynthesis inhibitors. 11) In this study, we screened commercial agrochemicals for compounds that inhibit dark-induced hypocotyl elongation in Arabidopsis to find the novel BR action regulators and investigated the inhibitory activities of BRs by fenoxycarb.…”