Parthenium hysterophorus L. is an aggressive weed of family Asteracea. It is native to the subtropics of North and South America but now has invaded Asia, Africa, and Australia, during the last 50 years. Since then the weed has not only naturalized itself in many countries but has spread at an alarming rate. In Pakistan it is spreading very fastly, affecting the Crops, Animal and Human Health related serious problems. Hence proper management of Parthenium is the cry of the day. Parthenium hysterophorus L. have allelopathic effect on weeds and crops of Pakistan and consider a serious threat to...