The potential yield of crop varieties will remain a mere illusion, unless and until proper weed management package is adapted. As all these varieties had been evolved under optimum weed management conditions, the weedy conditions of the farmers are not conducive for their yield. Under such circumstances, farmers’ own varieties or land races are better yielder and competitors as compared to the modern improved cultivars. Weeds inflict 20-30% losses in different crops on the average. On national level total monitory losses due to weeds well exceed beyond 120 billion, whereas wheat alone account for more than 30 billions. Losses in different crops is depicted in the following figure.

Figure: Total Yield losses due to weeds and their value at current market rate in various crops at National level.