Abstract

Agronanochemical for ganoderma fungal disease management

Author(s): Mohd Zobir Hussein, Sharida Fakurazi, Idris Abu Seman, Nur Hailini Zaino Hilmi, Isshadiba Faikah Binti Mustafa, Farhatun Najat Maluin and Saifullah Bullo

Oil palm is currently the world’s main vegetable oil crop due to its high productivity and long life span. However, the yearly harvest was significantly reduced, due to the basal stem rot (BSR) disease which is caused by a fungus, Ganoderma boninense. In 2010, the incidence of BSR disease was estimated to be about 3.7% with estimated affected areas of around 60,000 hectares. Losses due to Ganoderma disease is estimated to be about USD 0.5 billion. For the control of Ganoderma, integrated sanitation, biological and chemical controls were suggested. In the later, fungicides such as hexaconazole and dazomet were found effective to eradicate Ganoderma inoculum within infected stumps, therefore reducing the spread of Ganoderma. The chemical control can be further improved via nanotechnology platform through fungicide nanodelivery system (FUNADS), which is expected to prolonging the productive life of the infected palm, reducing the frequency of applying time by controlled release approach and to reduce the toxicity by enclosed it in biodegradable and toxic-free materials. In this work, two fungicides; hexaconazole and dazomet as the guests were encapsulated into nanomaterials as the hosts (chitosan and layered double hydroxides) for the formation of various FUNADSs using the host-guest supramolecular chemistry approach. The chemical structure of the synthesized nanofungicides was evaluated using x-ray diffraction (XRD), electron microscopy, dynamic light scattering (DLS), Fourier transform infrared spectroscopy (FTIR), and thermogravimetric (TGA/DTG) analyses. The DLS and high resolution transmission electron microscopy (HRTEM) show the FUNADs can be synthesised using various host and guest combinations, and can be turned into the nanoparticles by adjusting the synthesis parameters. In vitro fungicide release from the FUNADs shows a sustained release manner. Furthermore, in vitro anti-fungal studies of the FUNADs against G. boninense shows better inhibition and lower EC50 value compared to their counterparts, the bare fungicides.

This work is partly presented at 8th Edition of International Conference on Chemistry Education and Research August 27-28, 2018