This paper comprises mineral analysis of Cestrum diurnum lin leaves infected by powdery mildew fungus Oidium sp. The dried leaf samples of healthy and infected leaves were subjected to tri-acid digestion, according to method prescribed by Toth et al., (1948). The digested sample were used for analysis of minerals by atomic absorption spectrophotometer (Thermo scientific AAS 2003 model). The elements such as sodium, potassium and calcium were estimated by flame photometer, while phosphorous by Sekine et al., (1966) method. The elements such as iron, manganese, calcium, sodium and phosphorus were considerably enhanced in the infected leaves while potassium, zinc, copper and sulphur were reduced in infected leaves, reveals a great metabolic shift.

Keywords : Cestrum diurnum L minerals, Oidium sp., AAS Spectrophotometer, Flame photometer.