Defensive stratagems of plants, with special reference to allelopathy

The green plant has evolved an array of defences to ameliorate the effects of stresses in its environment. Allelopathy, biochemical interactions between plants, plays a role in plant defence but recent work suggests that some compounds which act as allelochemicals may also be effective in the defence of plants against other organIsms. Some examples of allelopathy in associations of crop and weed species are discussed in this context.