Agrotechnology
Neem grows in tropical arid regions with high temperatures, altitudes between 50m
and 1000m, as little rainfall as 130mm/yr and long stretches of drought. Well drained sunny
hill places are ideal. It grows on most kinds of soils including dry, stony, shallow, nutrient
deficient soils with scanty vegetation, moderately saline and alkali soils, black cotton,
compact clays and laterite crusts. However, silty flats, clayey depressions and land prone to
inundation are not conducive for its growth (Chaturvedi, 1993). Soil pH of 5.0 to 10.0 is
ideal. It brings surface soil to neutral pH by its leaf litter. It has extensive and deeply
penetrating root system capable of extracting moisture and nutrients even from highly leached
poor sandy soils.
Neem propagates easily by seed without any pretreatment, though it can be
regenerated by vegetative means like root and shoot cuttings. Seeds are collected from June
to August. These remain viable for 3-5 weeks only which necessitates sowing within this
short time. Seeds may be depulped and soaked in water for 6 hours before sowing. Seeds are
sown on nursery beds at 15x5cm spacing, covered with rotten straw and irrigated.
Germination takes 15-30 days. Seedlings can be transplanted after two months of growth
onwards either to polybags or to mainfield. Neem can be grown along with agricultural crops
like groundnut, bean, millets, sorghum and wheat. It is also suitable for planting in
roadsides, for afforestation of wastelands and under agroforestry system. For field planting,
pits of size 50-75 cm cube are dug 5-6m apart, filled with top soil and well rotten manure,
formed into a heap, and seedling is planted at the centre of the heap. FYM is applied at 10- 20
kg/plant every year. Chemical fertilizers are not generally applied. Irrigation and weeding
are required during the first year for quick establishment.
More than 38 insect pests are reported on Neem which may become serious at times.
The important ones are seed and flower insect (Scirtothrips dorsalis Hood), defoliators
(Boarmia variegata Moore and Eurema sp.), sap suckers ( Helopeltes antonii Signoret and
Pulvinaria maxima Green) , root feeders (Hototrichia consanguinea Blanchard), mealy bug
(Pseudococus gilbertensis), scale insect (Parlatoria orientalis) and a leaf webber
(Loboschiza Koenigiana)(Beeson, 1941, Bhasin et al, 1958, Parmar, 1995). They can be
controlled by the application of 0.01-0.02% monocrotophos or dimethoate. No serious
diseases are reported in Neem. Flowering starts after 5 years. In India flowering is during
January-May and fruits mature from May-August. The leaves are shed during February-
March and a full grown tree produces about 350 kg dry leaves and 40-50 kg berries per
annum. Fresh fruits give 60% dry fruits which yield 10% kernel which contains 45% fixed
oil, on an average. After 10 years of growth the wood can be cut and used as timber.
Properties and Activity
Dry Neem leaves contain carbohydrates 47-51%, crude protein 14-19%, crude fiber
11 - 24%, fat 2-7%, ash 7-9%, Ca 0.8-2.5% and P 0.1-0.2%. Leaves also contain the
flavanoid quercetin, nimbosterol (β-sitosterol), kaempferol and myricetin. Seed and oil
contains desacetylnimbin, azadirachtin (C 35 H 44 O 16 ), nimbidol, meliantriol ,tannic acid, S and
amino acids. Neem cake contain the highest sulphur content of 1.07% among all the oil cakes.
Trunk bark contains nimbin 0.04%, nimbinin 0.001%, nimbidin 0.4%, nimbosterol 0.03%,
essential oil 0.02%, tannins 6.0 %, margosine and desacetylnimbin (Atal and Kapur, 1982;
Thakur et al 1989).
Neem bark is bitter, astringent, acrid, refrigerant, depurative, antiperiodic, vulnerary,
demulcent, insecticidal, liver tonic, expectorant and anthelmintic. Leaves are bitter,
astringent, acrid, depurative, antiseptic, ophthalmic, anthelmintic, alexeteric, appetizer,
insecticidal, demulcent and refrigerant. Seed and oil are bitter, acrid, thermogenic, purgative,
emollient, anodyne, anthelmintic depurative, vulnerary, uterine stimulant, urinary astringent,
pesticidal and antimicrobial (Warrier et al, 1993).