Hydrogel-delivered strigolactone blocker curbs parasitic weed germination and aids rice tillering, study says
Researchers in China report in Nature Communications that a pH-responsive chitosan gel releasing a compound called DK6 held back parasitic weed germination and changed rice growth in their experiments.
Key points
- 1Starting from the SL inhibitor KK094, the researchers designed 32 indole derivatives and found DK6 to be the most active.
- 2They embedded DK6 in a pH-responsive, manganese-coordinated chitosan hydrogel (CMCS-DK6) that releases it steadily under alkaline conditions, the paper says.
- 3The authors report strong inhibition of parasitic weed germination, notably Striga asiatica (IC50 = 1.80 μM).
- 4In rice, the formulation promoted tillering, reduced plant height and increased dry weight, according to the study.
- 5Simulations and transcriptomics suggest DK6 binds SL receptors and suppresses SL signaling; the authors call the mechanistic findings potential.
Full story
Researchers at China Agricultural University and Guizhou University report a gel that slowly releases a compound blocking strigolactone signaling. In their experiments it curbed the germination of parasitic weeds and made rice plants form more tillers. The paper appeared as an open-access article in Nature Communications. The journal says this is a peer-reviewed, accepted version shared early, and that it may still be edited before the final Version of Record replaces it.
The work centres on strigolactone (SL) signaling, which the authors see as a useful handle in agriculture both for steering plant branching and for fighting parasitic weeds. Starting from a known SL inhibitor named KK094, the team designed 32 indole derivatives. Of these, a compound called DK6 performed best, according to the paper.
To make DK6 more soluble and more bioavailable, the researchers combined it with a carboxymethyl chitosan hydrogel coordinated with manganese, which they call CMCS-DK6. The gel reacts to pH and, the authors write, keeps releasing its cargo over time when conditions are alkaline. They report that CMCS-DK6 strongly held back the germination of parasitic weeds, with Striga asiatica the clearest case, for which they give an IC50 of 1.80 μM. In rice, they say, the formulation promoted tillering, made plants shorter and raised their dry weight.
To explore how the compound works, the team used molecular simulations together with microscale thermophoresis measurements. According to the authors, these results suggest that DK6 binds stably to SL receptors. Their transcriptome analysis indicates, they write, that DK6 dampens SL signaling, shifts several metabolic pathways and works together with hormone pathways to regulate tillering.
The authors frame their conclusions with care: they say the study provides a hydrogel delivery approach and “some potential mechanistic implications” that could inform efforts to shape crop architecture and to control weeds. The research was funded by the National Key Research and Development Program of China, and the authors declare no competing interests. Weiming Tan is the corresponding author.
Why it matters
Strigolactone signaling is linked both to how plants branch and to parasitic weeds, and the authors present their gel as one approach to improving crop architecture and weed control together. The results are reported by the authors themselves; the abstract does not say whether the gel has been tried outside their experiments, for example under field conditions, and the mechanistic insights are described as potential. The published text is an early accepted version that may still change.
Timeline
· Published
Topics#Agriculture#Rice#Hydrogel#Parasitic weeds#Nature Communications
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