|Name||Mr. Ali Ozcan|
|Organization or Institution||University of Central Florida|
Locally Systemic Pesticide (LSP) approach to combat Against bright spot disease of tomato
Ali Ozcan1,3, Mitsushita Doomra1,2, Mikaeel Young1,2 , Swadeshmukul Santra1,2,3,4
1NanoScience Technology Center, 2Burnett School of Biomedical Sciences, 3Department of Chemistry and 4Department of Materials Science and Engineering University of Central Florida,12424 Research Parkway, Suite 400, Orlando, FL 32826, USA
Bacterial spot of tomato caused by Xanthomonas strains represents a major production challenge in Florida and many tropical and sub-tropical regions worldwide. Copper (Cu)-based bactericides constitute the only current choice available to growers for disease management. However, X. perforans, which is the dominant factor for bacterial spot of tomato species in Florida, exhibits Cu tolerance, making disease management with standard Cu pesticides extremely challenging.
This project aims at developing a novel Cu-based locally-systemic pesticide (LSP) material using nanotechnology incorporating Cu and Quat actives to significantly increase the number of bactericidal mechanisms against X. perforans. Cu is present in the silica gel in the form of hydroxide/oxide nanoparticle. HRTEM data reveals that Cu nanoparticles are ultra-small (~ 5.0 nm) and crystalline. XRD and XPS confirmed that Cu nanoparticles doped are in the form of CuO. Phytotoxicity studies were carried on tomato plants and It was observed that LSP formulation containing 300 µg Cu/mL and 75 µg Quat/mL was non-phytotoxic. In-vitro antimicrobial studies demonstrated that MIC for LSP against both Cu susceptible and tolerant bacteria 4 ppm Cu/ 1 ppm Quat concentration, while standard film-forming Cu hydroxide based commercial product had MIC values 125 ppm and 250 ppm, respectively. The release kinetics of actives from LSP material was quantified using AAS for Cu, and LC-MS for Quat. It was found out that Cu is bound to LSP while Quat is removed slowly after each washes. It can be concluded that Quat can provide immediate protection upon spraying while Cu provides more extended protection.