The use of organic matter in the soil is an old
practice considered essential for sustaining the
thriftiness and productivity of crop. In addition to
providing necessary nutrient elements, organic matter
also influences soil physical characters such as pore size,
aeration, temperature, water retention capacities etc.
These help in better solubilization of minerals which
together with the nutrients released by decomposing
matter help in rapid extension of the root system, better
uptake of nutrients, retention of added nitrogen for a
longer period and finally better plant vigor even if the
disease has not been significantly checked (Singh,
1983). Neem plant (Azadirachta indica) possesses
biologically active compounds, mainly alkaloids such as
isoprenoids that control various pests including fungi
(Anwar-ul-Haq, 1993)