From sustag@beta.tricity.wsu.eduSun Nov  3 10:50:00 1996
Date: Fri, 1 Nov 1996 08:02:38 -0800 (PST)
From: "Tom Hodges (moderated newsgroup)" <sustag@beta.tricity.wsu.edu>
To: Principles of Sustainable Agriculture <sustag-l@listproc.wsu.edu>
Subject: Re: Nutrient content (fwd)



---------- Forwarded message ----------
Date: Fri, 1 Nov 1996 12:03:46 GMT
From: Geraldo Defune <pah_gd@wye.ac.uk>
To: "Jennifer L. Wilkins" <jlw15@cornell.edu>
Cc: "Tom Hodges (moderated newsgroup)" <sustag@beta.tricity.wsu.edu>
Subject: Re: Nutrient content (fwd)

Dear Jennifer & sustag friends,

I cannot provide refs for your specific questions besides 2 
general ones: Koepf, HH "Biodynamic Agriculture" and Kolisko's 
"Agriculture of Tomorrow" - they have data and refs. on the effects 
of heat and light on plants and food quality. 

I can say that growing methods that involve heat and light management 
(silica sprays) DO affect food quality as you can see in my included 
abstract.

Hope it helps!

Cheers,

Geraldo DEFFUNE
G.Deffune@wye.ac.uk or pah_gd@lister.wye.ac.uk 
Wye College - University of London - Agriculture Section 
Sustainable Agriculture Research Group 
Wye, Ashford, Kent TN25 5AH, England, U.K.
Tel.:(44-1233)813260, Fax: (44-1233)812855
WEB http://www.wye.ac.uk/agriculture/sargintro.html
PhD Student sponsored by CNPq - The Brazilian Research Council

---------- Forwarded message ----------

4th Congress of the European Society for Agronomy


Oral presentation                  Abstract

      INFLUENCES OF BIO-DYNAMIC AND ORGANIC TREATMENTS ON YIELD AND 
      QUALITY OF WHEAT AND POTATOES: THE WAY TO APPLIED ALLELOPATHY?

G.Deffune (1), A.M.Scofield, H.C.Lee, J.M.Lopez-Real and P.Simunek 
Sustainable Agriculture Research Group and Biological Sciences Dept.
Wye College, University of London,  Wye, Ashford, Kent TN25 5AH, U.K.

Many organic substances have allelopathic effects in agroecosystems 
(Rice 1984). Bio-dynamic preparations were the first set extracts
and solutions used as applied allelopathy in farming systems (Deffune
1990). This method has been succesfully used by Brazilian farmers
(Pio 1984) and worldwide, with great potential regarding biodiversity
and discovery of new active principles.

Double-blind field trials using spring wheat and potatoes with rye+vetch 
rotations, supplemented by glasshouse and axenic experiments, compare 
Organic, Bio-dynamic and Agrochemical systems. Yield and health, 
nutritional and keeping qualities of produce as well as soil and 
compost nutrient status are evaluated.

Significant quality differences, in terms of Thousand Grain Weight** 
and baking properties (HFN*) for the wheat; potato DM%***,conservation* 
(tissue browning) and amount of "chats"* (tubers<40mm) after a 6 month 
storage period, indicate the presence of allelopathic stimulation through 
quality assessment (Smith 1993). Results show the possibility to improve 
crop yield and quality of produce, through simple techniques, directly 
available to farmers (Reganold 1993).

   Deffune G 1990 - Unpublished MSc Thesis, Wye College.
   Pearce SC 1992 Experimental Agriculture 28, 245-253.
   Pio DM et al 1984 Lebendige Erde 6, 269-274.
   Reganold JP et al 1993 Science 260, 344-349.
   Rice EL 1984 Allelopathy. Academic Press, Orlando
   Smith RL 1993  Journal of Applied Nutrition, 45(1), 35-39.

1 PhD Student sponsored by CNPq - the Brazilian National Research 
  Council. E-mail: g.deffune@wye.ac.uk


