Formulation, characterization and antimicrobial activity of Rhus coriaria aqueous crude extract

Currently used copper-based pesticides and fungicides caused bacteria and fungi to develop resistance. Therefore, other environmentally friendly methods are being encouraged. Successful biopesticide usage is greatly reliant on suitable development of formulation. Four different surfactants (Emereen 1810, Emereen 1604, Emereen 1820 and Tween 20)were used to formulate Rhus coriaria aqueous extract. Stability, thermostability, particle size distribution, surface tension, shelf life were tested. The formulation was evaluated for its efficacy in controlling two of the most destructive fungi (Fusarium oxysporum (Acc No. KM039054)and Colletotrichum boninense (Acc No. KM039057)and two common bacteria (Xanthomonas vesicatoria (Acc No. KU661975)and Ralstonia solanacearum (Acc No. KT783476)in vitro and in vivo. From the four surfactants Emereen 1820 showed to be the best surfactant and was stable after six months of storage. A surface tension value of nanoemulsion solution was 27.174 mN/m, while particle size was 70.44 nm. Even after incubation and storage for up to twelve months, the formulation was stable and effective as well as efficient as compared to common commercial fungicides and antibiotics. Results indicate that R. coriaria nanoemulsion can effectively be used for the management of tomato pathogens as an eco-friendly approach.