According to the Board of Science and Technology for International Development, USNRC, Neem of plant has the potential to usher in a new era in pest control, provide millions with inexpensive medicines, cut down the rate of population growth, reduce soil erosion, slow down the deforestation mania and checking global warming. The origin of Neem is traced to Burma (Myanmar) and there exists (not cultivated) more than 60 million tress in the world with China and India accounting for more than 47 million of them. Till recently India was the leading country in propagation of Neem but China has taken over the lead with an estimated 25 million trees in that country. Why should Neem get the attention it has received and whether all the claims about its omnipotent power are realistic are worth considering.
Traditionally Neem leaves were being used as an insect repellent at the household level which is practiced in many rural areas even to day. Keeping Neem leaves with grains to protect them from insects or using these leaves to repel silverfish that can destroy cloths or heating water with the leaves for bathing can be seen in the rural backyard of the country. Neem is claimed to contain about 100 bioactive compounds but only a few have been researched thoroughly regarding their identity and efficacy as pesticides or medicine. The miraculous attributes to Neem can be gauged from the fact that it is called 'Mwarobaini' in Africa, meaning Tree of 40 that can cure 40 different types of diseases in Man. In India Neem is also referred to as 'Divine Tree', 'Heal All', 'Nature's Drugstore', 'Village Pharmacy' and 'Panacea for All Diseases'. Different parts of Neem plant are effective against 537 species of insects that include Ostracods, mites and ticks, nematodes, some species of snails and fungi. It does not kill the insects unlike the synthetic pesticides but incapacitates them. Neem oil is in great demand for treating skin infection, ring worm infestation, foot rot, scabies, lice, burn wounds, bruises etc.
The bioactive chemicals that make Neem command the attention world over include Nimbin, Nimbudin, Nimbidol, Gedunin, Quercetin, Salannin, Vepol, Meliantriol, Azadirachtan and others. About 40 of these chemical constituents act synergistically to confer on Neem the unique ability as antiviral, antifungal, antimicrobial, antipyretic, antiinflammatory, antitumor, analgestic, immune stimulating, alterative to restore heath, anthelmintic and anti-emitic agent. Seeds, leaves, flowers and bark are commonly used for achieving different results. Tetranortriterpenoids or liminoids which are similar to steroids in nature are the most effective components present in Neem. Azadirachtan, the most studied chemical constituent, is available in concentrated forms for varied applications. Neem oil which is rich in this chemical is widely available in India for use for external application against skin ailments. The pesticidal activity of Neem is due to the interference of the bioactive chemicals in the hormonal functions in the insect resulting in depressed feeding, cutting down on breeding and metamorphosing. Neem is harmless to friendly vectors like spiders, butterflies, bees, ladybirds and earthworms that populate agricultural lands.
It is difficult to imagine Neem as a food material because of its intense bitterness but tender leaves are some times consumed just like a green vegetable in some parts of India. Neem leaves preparations in dried powder form and encapsulated are also available for use as a general Ayurvedic tonic with several benefits attributed to it. In some states like Karnataka and Andhra Pradesh , during the new year festival Neem leaves and Flowers are consumed with jaggery, probably signifying that life can be bitter as well as sweet and resolving to face both with equanimity is inevitable. A flourishing trade exists with regard to neem oil and deoiled neem seed residue, widely used as natural pesticides and manure, especially for organic food cultivation. It is predicted that the global trade in Neem may exceed $500 million within the next 5 years and India will have to go in for organized cultivation on a massive scale to tap this emerging market.
A pro-active policy to popularize Neem cultivation in the country can have far reaching implications to the health of its population. The Forest Departments in various states are already propagating its planting along with many other fast growing species of perennial trees by distributing saplings free and providing useful information for their tending. Probably a conscious decision to plant this miracle tree on both sides of thousands of kilometers of Federal and State Highways will go a long way in creating an environment that is protective to the public as well as deriving economic benefits to the nation. On a conservative estimate, more than a billion trees can be planted within the next 10 years under a National Plan involving panchayats, urban bodies, NGOs, District Administrations, State Governments and Central Ministries. Food Industry can play a role in this by consciously planting Neem in and around their processing facilities which can ensure a much cleaner environment for handling foods.