Novel fungicide compositions prepared from neem seeds are disclosed. Two distinct neem derived fungicides obtained non-polar, hydrophobic solvent neem seed extracts which are substantially free of azadirachtin, by removing the hydrophobic solvent and cooling the resulting neem oil to separate a semi-solid neem wax fraction and a clarified neem oil fraction.

Storage stable pesticide compositions comprising neem seed extracts which contain azadirachtin as the active pesticidal ingredient wherein the compositions are characterized by their non-degrading solvent systems and high concentrations, i.e., greater than 10 g/l, of azadirachtin. In one embodiment, the pesticide compositions contain solvent systems characterized as having greater than 50% by volume aprotic solvents and less than 15% by volume water. In a second embodiment, the pesticide compositions contain solvent systems characterized as having greater than 50% by volume alcohol and less than 5% by volume water.

The stability of an azadirachtin-containing solid preparation is increased if the preparation contains about 5% or less volatile polar solvents and 1% or less water. Reduction of the percentage of volatile polar solvents present in preparations of azadirachtin-containing solids to such levels improves the storage-stability of the solids without significantly degrading the azadirachtin in the solid. Solvents are preferably removed by drying the preparation at a suitable temperature for a time sufficient to reduce the level of water and volatile polar solvents to acceptable levels.

A novel method of controlling fungi is disclosed. The method involves contacting the fungi, or a surface to be protected from the fungi, with a neem oil fungicide derived from a neem seed extract. The neem oil is prepared by extracting dried, coarsely ground neem seeds with a non-polar, hydrophobic solvent to obtain a neem oil extract and then removing the solvent to obtain the neem oil.

Neem oil fatty acid distillation residue based pesticide which is storage stable, water soluble, environmentally safe and rich in bitter principles. It is obtained by saponifying the neem oil fatty acid distillation residue with an aqueous alkali, drying the resulting soap, allowing the resulting soap cake to cool down to room temperature, pulverising the soap cake, fortifying the resulting fines by mixing with a small quantity of neem oil, allowing the fines to dry at room temperature and if desired, forming an aqueous emulsion by mixing the pesticidal fines with water at room temperature. The fines may be enriched by mixing with a small quantity of a solvent extract of neem tree parts prior to allowing the fines to dry.