Ethnobotanical study on pesticidal plants used in Southwest Nagaland, India for the development of eco-friendly pest control system

Abstract

BackgroundManagement of crop pests has been a great challenge around the world. In this study, the plants that are traditionally used as pesticides in southwest Nagaland were identified and documented. Pesticidal plants are an effective alternative to harmful synthetic pesticides and they may help in the formulation of a diverse group of organic pesticides. MethodsInformation on pesticidal plants was obtained through field study and semi-structured interviews. 360 informants from 24 villages were interviewed. Data were analyzed through quantitative tools – use value (UV), informants consensus factor (ICF), fidelity level (FL), and family use value (FUV). Phytochemical analysis of selected plants was done. ResultsIn total, 113 species representing 104 genera and 46 families were documented as pesticidal plants. Asteraceae was the most preferred family as a pesticide with 17 species. Herbs were recorded for 43% of use which was the highest among the habitats. Out of 113 species, 105 species were used as insecticides. Leaf (57.3%; 98 species) was the highest use plant part as a source of pesticides. The highest UV was recorded for Nicotiana tabacum (0.46) with 165 use reports. The ICF value was recorded from 0.96 to 0.97. In regards to FL, several potential pesticidal plants including Azadirachta indica, N. tabacum, Capsicum frutescens, and Curcuma longa were identified with 100% FL each. Phytochemical analysis showed the presence of secondary metabolites like alkaloid, flavonoid, phenol, saponin, tannin, and terpenoid. ConclusionInhabited by a diverse tribal population, the southwest part of Nagaland is a hub of ethnobotanical knowledge. The present study was the first quantitative survey on the plants used as pesticides by the tribal communities of southwest Nagaland and would help modern pharmacology immensely in formulating organic pesticides.