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Re: more on biodynamics, linear thinking, and right questions
A comment on Valerie's point about stressed plants and
susceptibility. I first heard that fertilization practices
promote susceptibility to disease, as part of an argument on why
organic sources of nutrition were superior to synthetic fertilizers
(this was at an IFOAM conference at MIT about 12 years ago). I
didn't believe it, and said so publicly. After the session, a
distinguished, grey- haired British woman came up and explained to me
the error of my thinking, to which I politely acceded but continued
(in my arrogance) to disbelieve. She referred to a book written by a
French scientist (I don't read French) summarizing his life's work on
"human-induced" diseases of plants (and animals?). There was even a
name for it, although I've long forgotten it.
Not long after I returned to the halls of academe, I received in the
mail a hand-translated copy of the Table of Contents of this book,
sent of course by my helpful British correspondent still trying to
improve my breadth of vision. Just to confirm the rightness of *my*
disbelieving position, I trotted the pages around to three
pathologists in my department. One (the youngest and most "up" on
modern lit) said "utter nonsense". The second thought he might have
heard something about it. The third said, "sure, here is my file on
it". And sure enough, there was the scientific lit in support of the
notion that fertilization practices (most specifically pertaining to
N, and particularly forms of N) influence susceptibility to pathogens
(most particularly fungi, if memory serves).
I use this story in my Crop Ecology class to encourage undergrad
students not to disbelieve everything that they hear which might
contradict "conventional wisdom". This year, I had an "add-on" in
the form of two excellent articles (citations provided, as asked)
corroborating the notion that fertilizer applied in recommended
amounts can have unexpected side effects on the increased
vulnerability of target crop plants to pest attack.
(tangential note: These effects were unexpected because those
doing the fertility work had not asked the "right" questions -
just the usual "linear" question - does it increase yield?;
a more holistic approach such as that espoused by BD and
other organic (and some conventional) farmers would be to
explicitly recognize that changes to a system always invoke a
multitude of responses - not just the one you are hoping
for; for more on the perils of linear thinking, see Clark and
Weise, 1993 in the ASA publication Agricultural Research in the
Northeastern United States)
The two refs were:
J. Prod Agric 7(4)448-454 - D.D. Howard et al. (1994) - Nitrogen and
fungicide effects on yield components and disease severity in wheat.
Agron. J. 86:581-585 - Funderburk et al. (1994) - Modifying soil
nutrient level affects soybean insect predators.
So - although cosmic influences and transmutation are outside of my
sphere of belief, I know some outstanding and otherwise rational BD
farmers (mostly dairy, one veggies) who swear by them. I have seen
with my own eyes phenomena which I cannot explain with any
scientifically accepted theory - such as systematically killing
large tracts of quackgrass with some BD preparation applied in
minisculel quantities at a certain stage of the moon. As a result, I
am trying to keep an open mind, although references such as those
noted above are a real comfort to those of us trained in the
conventional way.
Perhaps scientific support for the notions of BD - such as that for
soil nutrient x pest interactions - will accrue when more scientists
are able to believe what they see (and learn how to explore it with
rigor), instead of just adhering to what they read. Ann
ACLARK@crop.uoguelph.ca
Dr. E. Ann Clark
Associate Professor
Crop Science
University of Guelph
Guelph, ON N1G 2W1
Phone: 519-824-4120 Ext. 2508
FAX: 519 763-8933