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What are Microbial Inoculants?
SoilRenu
contains a large variety of microbial inoculants, enzymes, vitamins and
minerals (humate). SoilRenu is a unique formulation of these elements
and cannot be discussed in detail in order to protect the formula, however
SoilRenu contains this large variety of elements in order to support
virtually any type of plant. Not every plant has the same chemical
makeup and not every plant uses the same support structure either, therefore
those microbes or enzymes which are not used will either die off, be
ingested by other microbes or go dormant. The two main organisms used
by the majority of inoculated products are: Rhizobia and mycorrhizae.
These are the grandfathers, if you will, of the microbial families.
SoilRenu contains many more than just these two because in our studies we
have found there are far more beneficial microbes available for good soil
support. Many have been overlooked by others and ignored. Many
have been discovered to be of great value even those on the surface they
seem almost innocuous. SoilRenu has discovered which microbes and
which enzymes really are needed to maximize the growth effect.
Microbial
Inoculants by Category
Inoculants,
which are dry or liquid preparations of one or more species of
microorganism, fall into three broad groups: 1) those that inoculate
individual plants with symbiotic organisms (chiefly Rhizobia spp.),
2) those that inoculate the soil with desirable organisms, and 3) those that
are used as "cover crops" (algae).
Rhizobia
The most
clearly beneficial microbial preparations for agricultural use are the
different strains of Rhizobia used to inoculate legumes. Specific
strains of these bacteria live in a mutually beneficial (symbiotic)
relationship with specific species of legumes. The bacteria penetrate the
plant roots, causing the formation of root nodules containing both plant
tissue and bacteria. In very simple terms, the plant supplies the physical
environment and certain nutrients to the bacteria; the bacteria "fix"
nitrogen from the air into compounds that then become available to the
plant. Typical nitrogen fixation rates vary from 50 lbs/acre to over 300
lbs/acre, depending on climate, species, and soil conditions. On most farms
these rates make it possible to harvest good crops without purchasing
additional nitrogen.
Mycorrhizae
The
mycorrhizae (my-cor-ry-'zee) group of fungi live either on or in plant roots
and act to extend the reach of root hairs into the soil. Mycorrhizae
increase the plant's uptake of water and nutrients, especially in less
fertile soils. The superfine, root-like structures of these fungi are more
extensive and more effective than plant root hairs at absorbing phosphorus,
and other nutrients as well. Phosphorus moves slowly in soils but the fungi
can absorb it much faster than the plant alone can. This enhanced root
feeding makes it possible to reduce fertilizer rates for plants having a
healthy colony of mychorrhizae. Some plants including citrus, grapes,
avocados, and bananas, are dependent on mycorrhiza fungi. Others that
benefit from having them are artichokes, melons, tomatoes, peppers, and
squash.
Roots
colonized by mycorrhizae are less likely to be penetrated by root-feeding
nematodes since the pest cannot pierce the thick fungal network.
Mycorrhizae also produce hormones and antibiotics, which enhance root growth
and provide disease suppression. The fungi benefit from plant association by
taking nutrients and carbohydrates from the plant roots they live in.
In soils
where mychorrhizae have been killed off, an inoculation may be beneficial.
In healthy soils where they already exist there will be little or no benefit
to adding more. There are dozens of mychorrizae species in nature.
Additionally, the species found on plant roots may change as the plant
matures. If those that are available are of the correct species, and are
handled properly at all stages, they offer interesting potential benefits to
farmers in well-managed systems. Generally it is preferred to inoculate with
several species rather than a single one.
Free-living
soil organisms
A great many
of the products in this category are designed to be sprayed on the soil
surface or on crop residues in order to inoculate the topsoil with desirable
microorganisms. Manufacturers of these products make numerous and varying
claims about their beneficial effects, which fall into three broad
categories:
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The
microbes will fix enough nitrogen from the air to allow the farmer to
eliminate much or all fertilizer.
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The
product improves soil organic matter and "releases" soil nutrients to the
crop.
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The
product produces better yields, especially during times of drought.
Many
microbial products do indeed contain free-living (as opposed to symbiotic)
microbes that are known to fix nitrogen in certain circumstances. Those
species, however, work best in wet, oxygen-poor conditions that most farmers
and their crops would prefer to avoid. Rice paddies are a notable exception.
In the vast majority of cropping situations other than rice production, the
amount of nitrogen fixed by such free-living microbes is not generally
considered economically significant (3).
In other words, the value of any fixed nitrogen may be less than the cost of
the product. Far greater nitrogen fixation, for example, can be obtained via
symbiotic Rhizobia on a legume sod or cover crop, for much lower
cost.
Soil
microbes, like all living things, will thrive only in the presence of their
preferred environmental conditions-moisture, oxygen, temperature, pH, food,
and shelter. When conditions are not within favorable ranges, the microbes
cease reproduction or die. Natural microbial populations will be abundant if
soil conditions are right.
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