Biopesticide harpin to boost plant immunity, control fungal infections

Researchers at the University of Hyderabad (UoH) have demonstrated the ability to deliver the biopesticide harpin into plants and boost their immunity levels using nanotechnology.

They have developed a delivery system that uses harpin-loaded chitosan nanoparticles that help increase the bioavailability of the biopesticide to both improve immunity and drastically reduce the effects of a fungal infection.

The efficacy of the tool was tested in the tomato plant, where the team led by Appa Rao Podile, Vice-Chancellor, and Sravana Sandhya found a sharp decline in infection up to 80 per cent. The fungal infection in tomato crop is due to Rhizoctonia solani. They have published their work funded by the Department of Biotechnology in the Journal Carbohydrate Polymers. Fungi, bacteria, viruses and insects are the leading pests that challenge agriculture production. Synthetic chemical fungicides and pesticides are used to control plant diseases. Since these chemicals are often not degraded easily in the soil, they exert a damaging effect on environment.

The UoH researchers from the Plant Sciences and Biotechnology departments used the bio-active protein called harpin, taken from a phyto pathogenic bacterium, which is biodegradable. The approach is akin to the immunisation of humans using the killed or attenuated forms of pathogen for subsequent protection against the same pathogen, they said.

Technology transfer

The University has tied up wih Sri Bioaesthetics to produce both the harpin and the harpin-loaded chitosan nanoparticle.

The University has been working on Chitosans, which have a wide range of potential applications, including anti-fungal properties.

The team used chitosans in nanoparticle size to carry the biopesticide harpin in the delivery system. The chitosan nanoparticles’s ability to get into the plant through the pores on the leaves and spread into the cells was tapped to achieve the best results, they said.