Almost 80% of applied insecticide goes to non target sites including soil, water, and air that pollute the environmental components as well as break down the ecological correlation. Correlations between application losses of insecticides with different plant growth stages have been observed. This book will provide information how to measure the application loss of insecticide in field level, residue status from fruit and soil of the experimental field and finally find out a point when insecticide application is effective against destructive pest of Eggplant (Solanum melongena).