The use of botanicals as pesticides: History, development and emerging challenges

Abstract

The unrestrained use of artificial pesticides over the years has strictly affected the function and dynamics of the ecosystem. The plants are a valuable store providing natural secondary metabolites that can be used as alternative pesticides that are non- pollutive, inexhaustible, everlasting, locally available, simply accessible, environment-friendly and comparatively profitable. It is against this background that scientists have made relentlessly effort to come up with botanicals that can be used as pesticides. The use of botanicals as pesticides has witnessed a rapid expansion in recent years. Plant extracts like nicotine were some of the earliest agricultural botanicals used as early as 17th century. An increasing number of experiments on bio-pesticides occurred in the rapid institutional growth of agricultural research of the early 20th century. Revival in academic and industrial research with a view to developing bio-pesticides transpired in response to increasing costs related with the overexploitation of artificial chemicals. The emergence of novel bio-pesticides has persistently increased since the mid-1990s. Nowadays more and better botanicals are used as pesticides. However, bio-pesticides or botanicals have their limitations some of which include its slower rate of kill in comparison to orthodox chemical pesticides, shorter persistence in the environment and susceptibility to unfavourable environmental conditions. For effective use of bio-pesticides there is need for knowledge-intensive management systems. Plant protection biologists have a sole duty to facilitate an understanding of bio-pesticide efficacy and as well ensure that innovation and knowledge are properly disseminated towards the progress and implementation of sustainable approaches.