Azadirachta indica A.Juss. (Syn. Melia azadirachta L . ) ; Eng- Margosa tree, Neem tree; Hindi- Neem (Meliaceaae). A common roadside tree bearing small, white and sweet scented flowers. Blossoms in early April in North Indian conditions. Tree is considered a good purifier of air, due to its large leaf area. Native of Burma but grown all over India. Oilcake, obtained from seeds, is used as a fertilizer and manure. Green twigs are used as tooth brushes for cleaning teeth, and as a prophylactic for mouth and teeth complaints. Parts of the plant are used medicinally and the leaves are placed in suit cases to repel insects and to preserve woollens. An extract of leaves is used in tooth pastes and soaps Seeds yield famous margosa oil of disagreeable garlic like flavour. Oil is said to be effective in treatment of leprosy and skin diseases. Also used as a cure for manage in dogs. Leaves in poultice are used for healing of wounds. Ripe fruits are edible. Due to its bitter taste and disagreeable odour, not removed by conventional methods, neem oil has not been utilised on an industrial scale. However, a process has recently been developed to extract the bitter constituents from neem oil. Oil thus obtained has been found to be suitable for soap making and for hydrogenation. Seed oil is also used as antiseptic and for burning purposes. Stones from fruits are used as beads in rosaries and necklaces. Azadirachtin, a substance isolated from the tree, has been found to have insect repellent and insecticidal properties. Bark yields tannin. Gum exudate from the bark is used in medicines as a stimulant, and for dyeing silk. Bark is useful in fever, nausea, vomitting and skin disease. Bitter principles of neem oil are reported to have been obtained by extraction with alcohol. The main component of the oil is nimbidin which is very bitter. Nimbidin is used for making several pharmaceutical preparations including emulsions, liquors, ointments, medicinal cosmetics such as lotions, shampoos, creams, hair tonics and gargles. Timber is used for agricultural implements and furniture.
Besides above Neem products ? Neem EC and Neem UCA have also been produced as plant growth promoter and soil conditioning agent.
NEEM EC
NEEM EC is the general- purpose botanical pesticide of choice for organic agriculture . NEEM EC is widely used in several countries around the world today either singly in Integrated Pest Management or in conjunction with synthetic pesticides. Amongst the other known botanical pesticides such as Rotenone and Pyrethrins, NEEM EC is superior due to reasons cited below. Research has shown that neem extracts can influence nearly 200 spices of insects. It is significant that some of these pests are resistant to pesticides, or are inherently difficult to control with conventional pesticides (floral thrips, diamond back moth and several leaf miners).NEEM EC belongs to the category of medium to broad spectrum pesticides. NEEM EC works by intervening at several stages of the life of an insect. It does not kill the pests instantaneously but incapacitates it in several other ways.
Mode of Action : Neem acts as a biopesticide at different levels and ways. This is very important since the farmer is used to the knock out effect of chemical pesticides. Neem does not exhibit this type of effect on pests but affects them in several other ways.
Mainly: Oviposition Deterrent Insect Growth Regulation: It is a very interesting property of neem products and unique in nature, since it works on juvenile hormone. The insect larva feeds when it grows, it sheds the old skin and again starts growing. This particular shedding of old skin is the phenomenon of ecdysis or moulting is governed by an enzyme ecdysone. When the neem components, especially Azadirachtin enter into the body of larvae, the activity of ecdysone is suppressed and the larva fails to moult, remains in the larval stage and ultimately dies. If the concentration of Azadirachtin is not sufficient, the larva manages to enter the pupal stage but dies at this stage and if the concentration is still less the adult emerging from the pupa is 100 % malformed, absolutely sterile without any capacity for reproduction.
Feeding Deterrent: The most important property of neem is feeding deterrence. When an insect larva sits on the leaf, the larva is hungry and it wants to feed on the leaf. This particular trigger of feeding is given through the maxillary glands give a trigger, peristalsis in the alimentary canal is speeded up, the larva feels hungry and its starts feeding on the surface of the leaf. When the leaf is treated with neem product, because of the presence of azadirachtin, salanin and melandriol there is an anti ? peristalitic wave in the alimentary canal and this produces something similar to vomiting sensation in the insect. Because of this sensation the insect does not feed on the neem treated surface. Its ability to swallow is also blocked.
Oviposition Deterrent: Another way in which neem reduces pests is not by allowing the female to deposits eggs. This property is known as Oviposition deterrence, and comes in very handy when the seeds in storage are coated with neem Kernel powder and neem oil. The seeds or grains obtained from the market are already infested with some insects. Even these grains could be treated with neem seed kernel extract or neem oil; after this treatment the insects will not feed on them. There will be no further damage to the already damaged grains and at the same time when the female comes to the egg laying period of its life cycle, egg laying is prevented.
Other pesticidal activity includes of need include (1) The formation of chitin (exoskeleton) is also inhibited. (2) Mating as well as sexual communication is disrupted.(3) Larvae and adults of insects are repelled. (4) Adults are sterilised. (5) larvae and adults are poisoned.
Use of neem products does not give immediate results like chemical insecticides. Some patience is required after application of neem products.
Chemistry of Ingredients of Neem
Neem plants, as do all other plants, contain several thousands of chemical constituents.Of special interest are the terpenoids are known from different parts of the neem plant. Of its biological constituents the most active and well studied compound is Azadirachtin. However, in most traditional preparations of neem as pesticide or medicine a mixture of neem chemicals are present and provide the active principles. Several different kinds of azadirachtins (A to K) have been isolated, the most abundant of which is Azadirachtin ? A. The neem terpenoids are present in all parts of the plant, in the living tissues. Recently, the site of synthesis and accumulation of the neem chemicals has been identified as secretory cells. Secretory cells are most abundant in the seed kernels. The secretory cells can be seen with iodine solution. Besides the terpenoids, neem also contains more than 20 sulphurous compounds responsible for the characteristic smell of crushed seeds and neem oil.
Toxicity: In toxicological studies carried out in the USA and Germany, different neem product were neither mutagenous nor cancerogenic, and they did not produce any skin irritations or organic alternations to mice and rates even at high concentrations. In another Canadian study, Neem was found to be harmless to Aquatic invertebrates and other non-target species.
Besides above Neem products ? Neem EC and Neem UCA have also been produced as plant growth promoter and soil conditioning agent.
NEEM EC
NEEM EC is the general- purpose botanical pesticide of choice for organic agriculture . NEEM EC is widely used in several countries around the world today either singly in Integrated Pest Management or in conjunction with synthetic pesticides. Amongst the other known botanical pesticides such as Rotenone and Pyrethrins, NEEM EC is superior due to reasons cited below. Research has shown that neem extracts can influence nearly 200 spices of insects. It is significant that some of these pests are resistant to pesticides, or are inherently difficult to control with conventional pesticides (floral thrips, diamond back moth and several leaf miners).NEEM EC belongs to the category of medium to broad spectrum pesticides. NEEM EC works by intervening at several stages of the life of an insect. It does not kill the pests instantaneously but incapacitates it in several other ways.
Mode of Action : Neem acts as a biopesticide at different levels and ways. This is very important since the farmer is used to the knock out effect of chemical pesticides. Neem does not exhibit this type of effect on pests but affects them in several other ways.
Mainly: Oviposition Deterrent Insect Growth Regulation: It is a very interesting property of neem products and unique in nature, since it works on juvenile hormone. The insect larva feeds when it grows, it sheds the old skin and again starts growing. This particular shedding of old skin is the phenomenon of ecdysis or moulting is governed by an enzyme ecdysone. When the neem components, especially Azadirachtin enter into the body of larvae, the activity of ecdysone is suppressed and the larva fails to moult, remains in the larval stage and ultimately dies. If the concentration of Azadirachtin is not sufficient, the larva manages to enter the pupal stage but dies at this stage and if the concentration is still less the adult emerging from the pupa is 100 % malformed, absolutely sterile without any capacity for reproduction.
Feeding Deterrent: The most important property of neem is feeding deterrence. When an insect larva sits on the leaf, the larva is hungry and it wants to feed on the leaf. This particular trigger of feeding is given through the maxillary glands give a trigger, peristalsis in the alimentary canal is speeded up, the larva feels hungry and its starts feeding on the surface of the leaf. When the leaf is treated with neem product, because of the presence of azadirachtin, salanin and melandriol there is an anti ? peristalitic wave in the alimentary canal and this produces something similar to vomiting sensation in the insect. Because of this sensation the insect does not feed on the neem treated surface. Its ability to swallow is also blocked.
Oviposition Deterrent: Another way in which neem reduces pests is not by allowing the female to deposits eggs. This property is known as Oviposition deterrence, and comes in very handy when the seeds in storage are coated with neem Kernel powder and neem oil. The seeds or grains obtained from the market are already infested with some insects. Even these grains could be treated with neem seed kernel extract or neem oil; after this treatment the insects will not feed on them. There will be no further damage to the already damaged grains and at the same time when the female comes to the egg laying period of its life cycle, egg laying is prevented.
Other pesticidal activity includes of need include (1) The formation of chitin (exoskeleton) is also inhibited. (2) Mating as well as sexual communication is disrupted.(3) Larvae and adults of insects are repelled. (4) Adults are sterilised. (5) larvae and adults are poisoned.
Use of neem products does not give immediate results like chemical insecticides. Some patience is required after application of neem products.
Chemistry of Ingredients of Neem
Neem plants, as do all other plants, contain several thousands of chemical constituents.Of special interest are the terpenoids are known from different parts of the neem plant. Of its biological constituents the most active and well studied compound is Azadirachtin. However, in most traditional preparations of neem as pesticide or medicine a mixture of neem chemicals are present and provide the active principles. Several different kinds of azadirachtins (A to K) have been isolated, the most abundant of which is Azadirachtin ? A. The neem terpenoids are present in all parts of the plant, in the living tissues. Recently, the site of synthesis and accumulation of the neem chemicals has been identified as secretory cells. Secretory cells are most abundant in the seed kernels. The secretory cells can be seen with iodine solution. Besides the terpenoids, neem also contains more than 20 sulphurous compounds responsible for the characteristic smell of crushed seeds and neem oil.
Toxicity: In toxicological studies carried out in the USA and Germany, different neem product were neither mutagenous nor cancerogenic, and they did not produce any skin irritations or organic alternations to mice and rates even at high concentrations. In another Canadian study, Neem was found to be harmless to Aquatic invertebrates and other non-target species.
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