The prospect of "crops that fight weeds," in terms of crop
plants that exude natural herbicides to suppress competing weeds, is
attracting increased attention. The potential economic and environmental
benefits may be striking if this trait is exploited in much the same way
as defense mechanisms against insects or pathogens.
"The review illustrates that we have
a much better understanding of what
allelochemicals are produced by most of the
important crops and that we are making
progress in determining what genes control
The paper catches the wave of exciting recent advances in this research
area which have been achieved by scientists all over the world during the
past decade and identifies future research needs and prospects. This makes
it a valuable resource in the field of agricultural applications of
allelopathy. Allelopathy involves a plant's secretion of biochemical
materials into the environment to inhibit germination or growth of
Does it describe a new discovery, methodology, or
synthesis of knowledge?
The review integrates multiple and diverse recent findings in crop
allelopathy research, leading to a comprehensive, profound overview of the
state of knowledge in crop/weed interactions. Moreover, the integration of
various findings led to a new understanding of the mechanisms by which
crops and weeds interact and allowed us to highlight the features of
allelopathy that must be understood in order to fully exploit it for
Would you summarize the significance of your paper in
A growing public awareness of unwanted side effects from synthetic
herbicide applications is pushing the search for alternative weed
management methods. One possible option is the cultivation of crop plants
that can defend themselves by release of natural products to suppress
competing weeds. The paper gives an overview of the progress and problems
in this research area over the past decade and outlines some new ideas for
future progress and research directions.
How did you become involved in this research, and were
there any problems along the way?
I have been working on allelopathy issues for almost 10 years and view the
questions posed by this phenomenon as crucial to the understanding and
exploitation of crop/weed-interactions. However, for several decades the
utilization of allelopathy as an agricultural tool was hampered by the
scientifically weak nature of much of the published research.
With more rigorous scientists around the world working in this area during
the past decade, the situation has improved and new, powerful scientific
instrumentation and more sophisticated experimental strategies are now
available to put allelopathy in perspective. However, the challenge of
weeding with allelopathy still requires us to further refine our methods
and to expand the experimental scope much more at field level.
Where do you see your research leading in the
The review illustrates that we have a much better understanding of what
allelochemicals are produced by most of the important crops and that we are
making progress in determining what genes control their synthesis. Still,
much more needs to be done to fully understand the functioning and
efficiency of crop allelopathy systems and also to develop viable
management strategies for weed-suppressive cultivars. This requires a
multifaceted, interdisciplinary strategy among breeders, molecular
geneticists, weed scientists, agronomists, physiologists, and others.
Do you foresee any social or political implications for
Utilizing allelopathy for weed management could have the greatest impact on
synthetic pesticide use of any new technology. If the progress in crop
allelopathy research over the past decade can be exploited by plant
breeders and molecular biologists over the next decade, we can hope for new
crop varieties in the future that can reduce our current heavy dependency
on synthetic herbicides.
Regina G. Belz, Ph.D.
Lecturer and Research Assistant
Department of Weed Science, Institute of Phytomedicine
University of Hohenheim