India is playing a crucial role in development of neem
as pesticide in agriculture and pest control industry.
Neem in India is used for many purposes
Veterinary medicine
Unani medicine
Cosmetics
Malaria control
- public health
CROP PROTECTION AGENT
Nitrogen efficiency
Agro-forestry
Silviculture
Ayurvedic medicine
Ancient medicine
Agriculture
Modren medicine
Antifertility and other medical application
VEGETATIVE FEATURES
It is of the most valuable trees with multiple domestic uses and a good source of several
commercial by-products. In Ayurveda this tree is regarded as ‘Sarva Roga Nivarini’. Neem
also has many environmentally beneficial attributes. On account of the large canopy, the rate
of photosynthesis is high in neem: it releases high amount of oxygen during the day time as
compared to other trees. Hence it has a reputation as an air purifier. The tree increases soil
fertility and soil water-holding capacity. Neem can change the acidic soil of calcium mines to
neutral soil.
Neem is a deep-rooted hardy, medium to large tree which attains a height of up to 20 m and
a girth of 2.5 m. It usually has a short bole with wide spreading branches and glabrous twigs
forming a round to oval crown. The trunk often shows several burrs of various sizes. Neem is
evergreen except during February and March. New leaves arise at the tips of branches
immediately before or after the abscission of leaves. The bark is thick, dark-grey with
numerous longitudinal furrows and transverse cracks.
Leaves
Neem leaves are imparipinnately compound
alternate, exstipulate and 20-38 cm long and
crowded at the ends of branches. Each leaf
has a swollen base and bears 8 to 19,
opposite or alternate leaflets on a slender
petiole. The leaflets are short-stalked, ovate-
lanceolate, attenuated at the apex, with
unequally sided base, falcate, glossy and
bluntly serrate. The young leaves are reddish-
green, gradually turning into lush green or
dark green. A single vascular stand enters
the base of the leaflet which forms the
midrib. The midrib gives rise to secondaries,
tertiaries, quaternaries and intermediaries.
The secondaries arise at an angle of 40”
from the midrib and ramify to form a network.
Non-bitter Neem Tree
Neem is known for its bitterness. Almost every part of neem including neem oil has a sharp
pungent taste. However, there are instances of non-bitter neem trees. At Kothanur village,
about 20 km to the north-east of Kollegal town (Karnataka state) there is a neem tree in
which the stem appears to have become fused with a banyan tree (Ficus bengnalensis)
resulting in a natural graft. The leaves of this neem are not bitter. However, seedlings formed
from this tree have bitter leaves. Another tree at Mandya (Karnataka state), reported to have a
branch overhanging the wall of a temple, also does not have bitterness in its leaves.
Curiously the leaves of the rest of the branches of this tree are pungent. No convincing
botanical reasons for this phenomenon have been put forward although it could be a case of
bud mutation.
The areoles are of different sizes. The number of vein endings increase with the growth of
the leaf. The leaf is predominantly hypostomatic. Paliwal et al. reported paracytic stomata but
Farooqui noted anomocytic stomata in the plant. Development of stomata is
anomoperigenous. The leaf epidermis has compact polygonal cells. Cystoliths are present
in the cells towards the lower epidermis.