The crop having the highest pesticide use is

Cotton is one of the major commercial crops of India. Cotton covers only 5% of the total cropped area, but it accounts for nearly 50% of the consumption of overall pesticides which makes cotton the most chemically intensive crop in the world.
The major herbicides used on the cotton plantation are trifluralin, MSMA, DSMA, Prometryn, cyanazine, norflurazon, diuron and many more.