Polyoxin D is purified from the culture broth of actinomycetes and used as an agricultural fungicide. This compound shows antifungal activity against various plant pathogenic fungi, especially Rhizoctonia solani, by inhibiting germination, hyphal growth, and sporulation of the fungi. Its mode of action is thought to be via the competitive inhibition of chitin synthase, which causes incomplete cell wall formation and swelling in germ tubes, hyphae and septa. This action is unique and results in the suppression of diseases in various crops through fungistatic rather than fungicidal activity. Although the polyoxin complex shows not only fungicidal but also insecticidal activity, polyoxin D has less activity against insects, no negative impacts on the environment and is suitable for organic agriculture. Polyoxin D has the potential to control soil-borne and post-harvest diseases and to inhibit mycotoxin production via a new mode of action.

Emulsifiable concentrates and oil suspensions are typical pesticide formulations. Many pesticides on the market use aromatic hydrocarbons as solvents. However, studies have revealed their potential risks to humans and the environment. Ethylene glycol diacetate (EGDA) is a low-toxicity and eco-friendly solvent with low utilization in pesticides. This study explores EGDA’s potential to replace xylene. Results indicate that EGDA formulations enhance droplet adhesion to leaves, boosting pesticide efficiency. They exhibit lower surface tension and contact angles, with a 24%–40% increase in leaf retention. Bioassays show that 15% cyhalofop-butyl EC and 10% nicosulfuron OF with EGDA offer weed control that is superior to xylene-based formulations by 9.1%–30.5% in greenhouses and 4.8%–6.7% in fields. Xylene preparations are 2–3 times more cytotoxic to human bronchial cells than EGDA-based ones. Thus, EGDA is a promising pesticide solvent, outperforming traditional aromatic solvents in environmental friendliness and reducing adverse effects.

Root parasitic weeds from the Orobanche genus significantly damage crop production in African and European countries. Previous studies identified the metabolism of planteose, a storage trisaccharide in root parasitic weeds, as a potential control target. In Orobanche minor, α-galactosidase OmAGAL2 hydrolyzes planteose into sucrose upon perceiving germination stimulant strigolactones. Subsequently, invertases break down sucrose into glucose and fructose, essential for germination. This study screened chemical libraries to identify inhibitors against OmAGAL2-mCherry, secreted from transgenic tobacco BY-2 cells. Two inhibitors, 82-G8 and 85-B10, which significantly reduced the OmAGAL2 activity to less than 70% of the control, were evaluated for their impact on O. minor germination and sugar profiles. Results showed that OmAGAL2 inhibitors suppressed O. minor radicle elongation by inhibiting planteose metabolism, with effects more pronounced when applied at the start of conditioning rather than during germination stimulation. Further structural optimization could yield a novel class of chemicals for controlling Orobanche spp.

We investigated the synthesis and herbicidal activity of C5-substituted cinmethylin analogs. For the benzyl ether at the C2 position, we found that electron-withdrawing groups, such as halogen groups on the benzene ring have high herbicidal activity. Analogues with ketone, fluorine, and methoxy groups at the C5 position also showed excellent herbicidal activity.