A group of scientists at the University of Hyderabad (UoH) has turned to nanotechnology in order to address the poor bioavailability of harpin proteins. The team found out that harpin biopesticide brought about 80-90 per cent reduction in severity of fungal infection in tomato plants when it is encapsulated in chitosan nanoparticles.
Though harpin is used against several bacterial, fungal and viral infections, poor bioavailability is a major hurdle when harpin protein, taken from the bacteria Pseudomonas syringae pv. syringae, is just sprayed on the leaves like any other pesticide.
It was observed that bioavailability of harpin inside tomato plants increases sharply when loaded in chitosan nanoparticles. Also, less amount of harpin will have to be sprayed on leaves when it is contained in nanoparticles.
Currently, the shelf-life of harpin nanoparticle is limited to 30 days as the encapsulation loses its efficiency. The nanoparticles are being stored in a liquid phase. The team is trying to make some chemical changes at the time of preparation of chitosan nanoparticles to make it more stable.
The team is planning to test harpin-containing chitosan nanoparticles on a large-scale on four different crops and at least two pathogens per crop. Two of the crops to be tested will be grown in fields and two others will be greenhouse crops.