Green Science Alliance has developed an experimental pest-repellent material made from carbon quantum dots produced using wood, plant and food waste.

The Japanese materials technology company said the particles demonstrated a repellent effect against adult Bemisia tabaci, commonly known as the sweetpotato or silverleaf whitefly, during preliminary testing. The insect is an important agricultural pest that damages crops through sap feeding and the transmission of plant viruses. It can also infest potato crops in some production regions.

The carbon quantum dots were synthesised by Green Science Alliance chief executive Ryohei Mori using several forms of organic biomass waste. Quantum dots are nanoparticles whose physical and optical properties can differ from those of the same material at a larger scale.

Green Science Alliance described the results as a possible starting point for developing biomass-derived crop repellents. However, it did not disclose quantitative efficacy data, the experimental methodology or comparisons with existing pest-control products.

The company also said the mechanism responsible for the observed response remains unknown. Possible explanations under consideration include the particles’ light-emission and photocatalytic properties, although these have not yet been demonstrated as the cause of the repellent effect.

Further research will be required to establish the material’s efficacy under crop and field conditions, as well as its environmental behaviour, residue profile and safety. Green Science Alliance plans to produce carbon quantum dots from additional biomass waste streams and evaluate their potential against other pests.