Current Status of Plant Products as Botanical Pesticides in storage pest management

The increasing concern over the level of pesticide residues in food has encouraged researchers to look for alternatives of synthetic pesticides. Their indiscriminate use has led to the development of resistant strains of pests as well as different environmental and human health problems. Recently, in different parts of the world, attention has been paid towards exploitation of higher plant products as novel chemotherapeutants in plant protection. Because of non phytotoxicity, systemicity, easy biodegradability and stimulatory nature of host metabolism, plant products possess the potential in pest management. Used widely until the 1940’s, these natural pesticides were displaced by modern synthetic pesticides that at the time seemed cheaper, easier and long lasting. The popularity of botanical pesticides is once again increasing and some plant products are being used globally as green pesticides. The body of scientific literature documenting bioactivity of plant derivatives to different pests continues to expand, yet only a handful of botanicals are currently used in agriculture. Pyrethroids and neem products are well established commercially as botanical pesticides and recently some essential oils of higher plants have also been used as antimicrobials against storage pests because of their relatively safe status and wide acceptance by the consumers. Some of the volatile oils, which often contain the principal aromatic and flavouring components of herbs and spices, have been recommended as plant based antimicrobials to retard microbial contamination and reduction in spoilage of food commodities. Furthermore, some of the antimicrobial plant products also possess strong antioxidant activities which are favourable properties to combat free radical mediated organoleptic deterioration of plant commodities and enhancing their shelf life. In the context of agricultural pest management, botanical pesticides are best suited for use in organic food production in industrialized countries but can play a much greater role in the production and post harvest protection of food products in developing countries.