Nargund, V.B.Chidanandappa2024-07-162024-07-162018-07https://krishikosh.egranth.ac.in/handle/1/5810212121In this study chitosan based copper nanoparticles (Ch-CuNPs) and silver nanoparticles (Ch-AgNPs) were synthesized by utilizing water soluble chitosan (1%) and pomegranate aril extract (1.4%) with copper sulphate and silver nitrate as precursors at the College of Agriculture, University of Agricultural Sciences, Dharwad, during 2017-2018. Synthesized nanoparticles showed absorption spectra peak of 553 nm for Ch-CuNPs and 430 nm for Ch- AgNPs by UV-Visible spectrophotometer. Particle size analyser showed mean diameter of 71.60 nm and 89.39 nm for Ch-AgNPs and Ch-CuNPs respectively. Atomic Force Microscope showed nanoparticles having size ranged from 30 - 140 nm and 20 - 95 nm for Ch-CuNPs and Ch-AgNPs respectively. Scanning Electron Microscope revealed spherical to irregular shape of both nanoparticles. Synthesized Ch-CuNPs and Ch-AgNPs were evaluated against bacterial pathogen of citrus canker [Xanthomonas axonopodis pv. citri (Xac)] and pomegranate bacterial blight [Xanthomonas axonopodis pv. punicae (Xap)] under in vitro condition by paper disc assay. The results revealed that, Ch-CuNPs effectively inhibited growth of Xac (7.67 mm) and Xap (9.67 mm) at 4,000 ppm. Ch-AgNPs showed inhibition zone of 12.67 mm for Xac and 13.66 mm for Xap at 250 ppm. In glasshouse studies, management of citrus canker, Ch-CuNPs at 3000 ppm recorded PDI of 8.67 compared to untreated control (29.33 PDI). In case of Ch-AgNPs, the minimum disease severity was recorded at 250 ppm concentration (5.56 PDI) compared to untreated control (27.11 PDI). Evaluation of nanoparticles against management of bacterial blight of pomegranate revealed that, Ch-CuNPs were effective at 3000 ppm concentration with minimum disease severity (7.82 PDI) compared to untreated control (31.33 PDI). Further, Ch-AgNPs were effective at 250 ppm with the least disease severity (10.00 PDI) compared to untreated control (PDI 45.00 PDI). Ch-CuNPs and Ch-AgNPs against bacterial diseases of citrus and pomegranate, were effective at 3000 and 250 ppm respectively.EnglishThesis