Allelopathic Potential of Medicinal Plants Serves as a Valuable Source for Sustainable Weed Management

Weeds are noxious plants that cause major problems for crop cultivation by interfering with crop growth and development. Due to weed infestation, about 50% of crop yields are reduced. In fact, weed causes more damage than pests and diseases in crop production. In modern agriculture, weeds are managed by using synthetic chemical herbicides. However, in organic farming, weed management is only possible through conventional methods such as manual and mechanical weeding, which are uneconomical and labor-intensive processes. Nowadays, labor shortage is the major problem in agriculture for performing various intercultural operations, especially weed management. In addition, continuous usage of synthetic herbicides can cause contamination to the surroundings thereby resulting in environmental pollution and the evolution of several herbicide-resistant weed species. To address these drawbacks allelopathic potential and allelochemicals can be utilized for weed management. Medicinal plants are rich sources of secondary metabolites with allelopathic potential, which helps to manage weeds by using plants extracts and natural herbicides. Allelochemicals of medicinal plants have the greatest potential for biological weed management by utilizing plant extracts and extracted allelochemicals as natural herbicides. Naturally extracted allelochemicals have almost the same effect as that of using synthetic herbicides in weed management without causing hazards to the environment. Thus, natural herbicides play a vital role in maintaining eco-friendly agriculture and sustainability in soil health. This review will help to create a general view about the allelopathic potential of medicinal plants and also helps to identify future research areas for weed management in organic farming with the help of allelochemicals.