As can be seen from the above discussion, there are
now numerous examples of allelopathic effects that have
been established decades ago. Today we are still looking
for other allelopathic plants or weed species. Realisti-
cally, we have made a significant advances in this
direction over the last three decades. We still have a long
way to go in terms of using or developing plant species
that would be used for weed management or can be used
as companion crop.