Antifungal activity of biosynthesised copper nanoparticles evaluated against red root-rot disease in tea plants

The synthesis of metal nanoparticles is an emerging area of advanced research and technology with potential application in plant protection. In the current study, with an eco-friendly approach, a convenient method was adopted, where copper nanoparticles are biosynthesised extracellularly by using Streptomyces griseus. Further, the existence of nanoparticles was confirmed by UV–visible spectroscopy, transmission electron microscopy, X-ray diffraction analysis and Fourier transform infrared spectroscopy characterisation. We assessed the field effectiveness of copper nanoparticles through soil application in P. hypolateritia infested tea plants. In response to seven different treatments, carbendazim exhibited superior control followed by nanocopper at 2.5 ppm dosage. However, maximum leaf yield was observed in plants treated with nanocopper. In addition, nanocopper-treated plants showed improved soil macronutrients considerably when compared to bulk copper and carbendazim treated plants. In addition, there was trivial variation in population dynamics of microbes noted in plants treated with nanocopper. These encouraging results confirmed that nanocopper could act as an efficient novel fungicide which may be used for the management of red root-rot disease in tea plantations.