10.22376/ijpbs.2019.10.1.p1-12 Volume 6 Issue 1 2015 (January - March) In the present study,an attempt has been made to evaluate phytotoxicity of free and chitosan coated silver and copper nanoparticles against Vigna mungo under microplot condition and the toxic effect on soil microbial status and microbial population has been studied.Respective nanoparticles were synthesized by chemical reduction of respective metal salt precursor with reducing agents and polymer coated nanoparticles were by chemical reduction of respective metal salt precursor with reducing agent and further coating with chitosan.Synthesized nanoparticles were characterized by UV visible spectrophotometry,scanning electron microscopy,fourier transform infrared spectroscopy and energy dispersive x ray spectroscopy. Phyototoxicity of respective nanoparticles against Vigna mungo was studied under microplot condition. Effect of respective nanoparticles on the plant growth parameters such as shoot length, total foliage density, total number of new branches emerged and foliage surface area were studied. Among the nanoparticles treatment, drastic reduction on the all tested plant growth parameters including soil microbial population was recorded in free copper and silver nanoparticles treatment. But, soil enzyme activity was not affected in all the nanoparticles treatment. A.ARUNA, S.KARTHICK RAJA NAMASIVAYAM AND E.ALLEN ROY phytotoxicity, nanoparticles, Vigna mungo, chitosan, plant growth parameters 461-467