| New Generation Technology for Agriculture |
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| All Kinds of Animals, All Kinds of Vegetables, All Kinds of Fruit Bearing Trees. |
USE OF BENEFICIAL MICROORGANISMS (EM) IN AGRICULTURE
Agricultural production begins with
the process of photosynthesis by green plants, which requires solar energy, water, and carbon dioxide. These materials are
freely available. Therefore, it can be defined that "Agriculture is to produce something from nothing". Althought it sounds
good, when observed as an economic activity, present agriculture has an extremely low efficiency. This is due to the very
low utilization efficiency of solar energy by plants.
The potential utilization rate of solar energy by plants has
been estimated theoretically to be between 10 and 20%. However, the actual utilization rate is less than 1%. Even the utilization
rate of C4 plants, such as sugar cane which have a high photosynthetic efficiency, barely exceeds 6 or 7% during the maximum
growth period. The utilization rate is normally less than 3% even for producing optimum crop yields.
Past studies
have shown that photosynthetic efficiency of the chloroplasts of host crop can not be enhanced much further. This means that
their biomass production capacity has reached a maximum. Therefore, the best opportunity for increasing biomass production
is to utilize the visible light, which chloroplasts can not presently use, and the infrared radiation. These together account
for about 80% of the total solar energy. We should also explore ways of recycling organic energy contained in plant and animal
residues through direct utilization of organic molecules by plants.
In the presence of organic matter, photosynthetic
bacteria and algae can utilize wavelengths ranging from 700 to 1200 nm. Green plants do not use these wavelengths. Fermenting
microorganisms can also breakdown organic matter, thereby releasing complex compounds such as amino acids for plant use. This
increases the efficiency of organic matter for crop production Thus a key factor for increasing crop production is the availability
of organic matter, which has been developed by utilizing solar energy and the presence of efficient microbes to decompose
these materials. This increases the utilization efficiency of solar energy.
2.2 PRINCIPAL MICROORGANISMS IN EM AND THEIR ACTION IN SOIL
(1) Photosynthetic
bacteria (Phototrophic bacteria)
Photosynthetic bacteria are independent self supporting microorganisms. These bacteria
synthesize useful substances from secretions of roots, organic matter and/or harmful gases (e.g. hydrogen sulfide) by using
sunlight and the heat of soil as sources of energy. The useful substances comprise of amino acids, nucleic acids, bioactive
substances and sugars, all of which promote plant growth and development.
These metabolites are absorbed into plants
directly and also act as substrates for increasing bacteria. Thus increasing Photosynthetic bacteria in the soil enhances
other effective microorganisms. For example, VA (vesicular-arbuscular) mycorrhiza in the rhizosphere are increased due to
the availability of nitrogenous compounds (amino acids) for use as substrates secreted by Photosynthetic bacteria. VA mycorrhiza
increases the solubility of phosphates in soils thereby supplying unavailable phosphorus to plants. VA mycorrhiza can coexist
with Azotobactor as nitrogenfixing bacteria and enhance nitrogen fixing ability of legumes.
(2) Lactic acid bacteria
Lactic acid bacteria produces lactic acid from sugars, and other carbohydrates produced by Photosynthetic bacteria
and Yeast. Thus, food and drinks such as yogurt and pickles have been made by using Lactic acid bacteria for a long period
of time. However, lactic acid is a strong sterilizer. It suppresses harmful microorganisms and increases rapid decomposition
of organic matter. Moreover Lactic acid bacteria enhances the breakdown of organic matter such as lignin and cellulose, and
ferments these materials without causing harmful influences caused by undecomposed organic matter.
Lactic acid bacteria
has the ability to suppress Fusarium propagation which is a harmful microorganism causing disease problems in continuous cropping.
Generally, increased Fusarium populations weakens plants. This condition promotes diseases and also results in the sudden
increase of harmful nematodes. The occurrence of nematodes disappear gradually, as Lactic acid bacteria suppresses the propagation
and function of Fusarium.
(3) Yeasts
Yeasts synthesize antimicrobial and useful substances for plant growth
from amino acids and sugars secreted by Photosynthetic bacteria, organic matter and plant roots.
Bioactive substances
such as hormones and enzymes produced by yeasts promote active cell and root division. Their secretions are useful substrates
for effective microorganisms such as Lactic acid bacteria and Actinomycetes.
(4) Actinomycetes
Actinomycetes,
the structure of which is intermediate to that of bacteria and fungi, produces antimicrobial substances from amino acids secreted
by Photosynthetic bacteria and organic matter. These antimicrobial substances suppress harmful fungi and bacteria.
Actinomycetes
can coexist with Photosynthetic bacteria. Thus, both species enhance the quality of the soil environment, by increasing the
antimicrobial activity of the soil.
(5) Fermenting Fungi
Fermenting fungi such as Aspergillus and Penicillium
decompose organic matter rapidly to produce alcohol, esters and antimicrobial substances.
These suppress odors and
prevent infestation of harmful insects and maggots.
Each species of Effective Microorganisms (photosynthetic bacteria,
lactic acid bacteria, yeasts, actinomycetes and fermenting fungi) has its own important function. However, photosynthetic
bacteria is the pivot of EM activity.
Photosynthetic bacteria support the activities of other microorganisms. On the
other hand, photosynthetic bacteria also utilizes substances produced by other microorganisms. This phenomenon is termed "coexistence
and co-prosperity".
When Effective Microorganisms increase as a community in soils, populations of native effective
microorganisms are also enhanced. Thus, the micro flora becomes rich and microbial ecosystems in the soil become well-balanced,
where specific microorganisms (especially harmful microorganisms) do not increase. Thus, soil borne diseases are suppressed.
Plant roots secrete substances such as carbohydrates, amino and organic acids and active enzymes. Effective microorganisms
use these secretions for growth. During this process, they also secrete and provide amino and nucleic acids, a variety of
vitamins and hormones to plants. Furthermore, in such soils, effective microorganisms in the rooting zone(rhizosphere) co-exist
(symbiosis) with plants. Hence, plants grow exceptionally well in such soils which are dominated by effective microorganisms.
Source: EM Research
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