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ABSORBU absorbu at aol.com
Fri Mar 15 16:30:43 EST 1996

A fungi called "mycorrhyzae".

A little known family of fungi that inhabits the roots of nearly all of
the world's plants is creating great interest in an increasing number of 
forestry,  agriculture, horticulture and landscape  professionals around
the world.

The fungi can be found, on every grain of sand and every gram of soil from
the Arctic circle to the Equator, accounting for some 15% of the world 's
plant  roots, they comprise the greatest mass of microorganisms on the
planet earth. They are the biological link between the plant world and the
soil world.

Mycorrhizal fungi (Myco=fungus  -  Rrhizae=root)  form a symbiotic
association with the roots of most plants.  The fungi grow into or between
the cells of the roots and use ten percent of the carbohydrates the plant
passes from the leaves to the roots.  The fungi don't have chlorophyll in
the presence of sunlight, so they can't manufacture carbohydrates
(sugars).  In return for the energy taken from the plant, the fungi grow
out and search far and wide for nutrients and moisture and feed the plant
so it can continue to manufacture more and more carbohydrate energy.  The
bigger and faster the plant grows the further and faster the fungi grow to
feed the plant still better.  A plant colonized with  mycorrhizal fungi
will have the equivalent of ten times more root.  Another benefit of this
association is that as long as the fungi are flourishing, they can prevent
all root pathogens and damaging  nematodes from attacking the root.  The
fungal partnership increases plant resistance to drought, salinity,
acidity and diseases.

Mycorrhizae contribute specially to the uptake of phosphorus, one of the
three major nutrients needed by plants, and of  such trace elements as
copper and zinc. The fungi's hairs (Hyphae) extend the plant's reach and
also break down insoluble minerals that otherwise would be unavailable. 

In the 1970's the fungi was called "bionic fertilizer" as some scientists
predicted an agricultural revolution. Mycorrhizal research funding was
incremented by several major Corporations, but did not continue as the
general consensus reached was that it was hard to improve on nature. Since
then, although well known in scientific agricultural circles, mycorrhizae
has been extremely difficult to produce in commercial quantities. Mycorr
Tech Inc. a Pittsburgh, Pa. biotechnology  firm, acquired by Plant Health
Care Inc. in early 1995 pioneered a solid-state fermentation process to
commercially produce superstrains of the fungi, making it easier to use in
three specialized areas. 

First, inoculation of seedlings with the fungi promotes revegetation of
sites such as strip mined lands and roadsides where natural fungus
populations have been destroyed.

Second, the fungi can be added to soils in nurseries and orchards where
fumigation, often required to kill pests, has also suppressed the fungi.
Citrus and other fruits grown in fumigated soils will benefit from

Third,  where nursery greenhouse plants are grown in sterilized artificial
soils (potting mixes), the application of mycorrhizae will cut  the heavy
requirements for chemical fertilizers and water. Thus making  nursery
operations  more economical by reducing fertilization, watering and labor

The fungal products are now available from  PLANT HEALTH CARE INC., under
the name of MycorTreeTM.        Trees grown with MycorTree products show
remarkable improvements in survival and growth rates when compared to
traditionally produced nursery trees.  Growth rate differences in excess
of 300 percent  and reduction of mortality from 80 percent to less than 5
percent are the norm.

For information contact:

Plant Health Care, Inc.
941-758-1175 (Fax)

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